UNIVERSITY OF CALIFORNIA, SAN DIEGO 3 1822 04429 6622 OPTICAL SYSTEM GROUP TECHNICAL NOTE NO. 218 July 1990 Offsite (Annex-Jo rnals) QC 974.5 . T43 no. 218 18 PRELIMINARY OPERATIONS MANUAL FOR THE USE OF THE WHOLE SKY IMAGER REAL TIME CLOUD SYSTEM J. E. Shields R. W. Johnson G. Zawadzki UNIVERSITY OF CALIFORNIA SAN DIEGO The material contained in this note is to be considered proprietary in nature and is not authorized for distribution without the prior consent of the Marine Physical Laboratory and the Geophysics Laboratory SITY SA Contract Monitor, R. W. Endlich HEL Support Branch * FORN HEU LG • THE UTC *1868 VI Prepared for The U. S. Army Atmospheric Sciences Laboratory White Sands Missile Range, NM 88002-5501 under contract No. N00014-87-C-0127. SCRIPPS INSTITUTION MARINE PHYSICAL LAB San Diego, CA 92152-6400 OF OCEANOGRAPHY UNIVERSITY OF CALIFORNIA, SAN DIEGO met Www 3 1822 04429 6622 WAYEV TABLE OF CONTENTS INTRODUCTION....... i SYSTEM HARDWARE OVERVIEW......... i mi 3.1 RUNNING THE REAL TIME PROGRAM...... Overview.. ... 3.2 Finding and Starting the Program .... 3.3 The Start-up portion of the program .. 3.3.1 Exabyte Option........ 3.3.2 Track Option................. 3.3.3 Option of Changing Cloud Thresholds ... 3.3.4 Options for use of Program ........ 3.3.5 When to use the Enter Key............ 3.4 Program Sequence in Automated Mode .... 3.4.1 Available Data Lines on the Monitor..... 3.4.2 Sequence of Operations shown on RGB Screen 3.5 Use of Hot Keys ..................... 3.5.1 "C" Hot key .. 3.5.2 "D" Hot key .. 3.5.3 "T" Hot key 3.5.4 "S" Hot key .... 3.5.5 "R" Hot key ...... 3.5.6 "X" Hot key .................. 3.5.7 Use of other hot keys .............. 3.5.8 Use of the "L" hot key for looping ....... 3.6 Summary of Program RTIMCLD Use ............. REAL TIME PROGRAM STRUCTURE AND FUNCTION .. 4.1 Main Functions of the Program ......... 4.2 Deriving the Cloud Decision Image..... 4.3 Timing s and Format of the RS232 Signal.. INTERPRETATION OF THE CLOUD DECISION DISPLAY, 5.1 Normal Display Format...... 5.2 Track and Color Bars.... 5.3 Selection of Thresholds for Optimal Display. 6.1 CREATING THE TRACK DATA FILE USING THE MS EDITOR. Format of the Track Data File. 6.2 Creating an MS File ................. 6.3 Editing an Existing MS File ...... 6.4 Other Useful MS Features ...... V VV VIW .. . . .. . . . . . . . . . . . . . . . . . . THE CLDSAVE PROGRAM TO SAVE RATIO FILES . 7.1 Overview.. .... 7.2 Required Disc Space ....... 7.3 Running the CLÕSAVE Program ... .i. Table of Contents con't. 8. OTHER USEFUL COMPUTER FUNCTIONS . 8.1 Changing Directories 8.2 Deleting Files. ..... 8.3 Program EXBACK for Saving Files....... 8.4 Program EXRCVR for Recovering Files ..... ......................... TROUBLE SHOOTING ...... 9.1 Computer Start-up Failure .... 9.1.1 System Hangs with No Message .. 9.1.2 Hard Disk and/or Controller Failure.. 9.1.3 CPU Failure ...................... 9.2 Missing or Abnormal Imagery on Line A... 9.2.1 No Image Present ...... 9.2.2 Images Appear Dark ... 9.2.3 Images Appear Noisy ..... 9.3 Missing or Abnormal Imagery on RGB Line. 9.3.1 No RGB Image ........ 9.3.2 "Pepper" on Image .............. 9.3.3 Other RGB Abnormalities ..... 9.4 Image on RGB stays Black, with "Awaiting Sync" Message.. 9.5 System Appears to Hang During a Program Run ... 9.6 Occultor Looks Abnormal......... 9.6.1 Occultor is Not Aligned with the Sun on Line A . 9.6.2 Occultor Mask is not lined up with Occultor ...... 9.7 Cloud Indication is consistently clear or overcast ......... 10. RECOMMENDED SYSTEM REFINEMENTS....... 10.1 Short Term Refinements .... 10.1.1 Cloud Cover along Track Projection .. 10.1.2 User Interface. 10.1.3 General Cleanup ..... 10.2 Longer Term Refinements 10.2.1 Prediction .. 10.2.2 Cloud Discrimination Algorithms ..... 10.2.3 Cloud Base Detection .. 11. SUMMARY ... CAUTIONARY NOTE.......... 13. ACKNOWLEDGEMENTS. Appendix A: Detailed Instructions for use of MPL Programs EXBACK and EXRCVR, for file storage to Exabyte - ii - LIST OF FIGURES Fig. # Figure Title Page 1.1 1.2 2.1 ... Sample RTim Cld Display ..... Sample Loop of 4-images acquired at 10-minute intervals...... Hardware Block Diagram, Whole Sky Imager System with Added Computer Unit for Real Time Cloud Determination ..... Program Start Up Options ........ 3.1 Progrdey Options in RTIMCLL, "Y" if th 3.2 3.4 3.3 First Text Display in RTIMCLD: Introduction and Exabyte Option .... First Text Display after answering "Y" if there is a tape in the Exabyte 3.5 First Text Display after answering "Y" if no tape is present ... 3.6 Second Text Display: Addresses Track File Option ... 3.7 Second Text Display after entering track file name .. 3.8 Third Text Display: Addresses Cloud Threshold Option 3.9 Third Text Display after entering new cloud thresholds. 3.10 Fourth Text Display: Addresses Program Mode Option ...... 3.11 Response following Fourth Text Display if user requests "R" for Retrieve ................ 3.12 Fourth Text Display, after user requests "L" for Loop 3.13 Sample Raw Data Images ..... 3.14 Sequence of Operations seen on RGB Line .... 3.15 Cloud Decision Image Display.............................. 4.1 4.2 4.3 Program RTIMCLD Conceptual Flowchart... Cloud Decision Image Computation ...... False Color Used on Cloud Image.......... Effect of Varying Thresholds........... 5.1 6.1 Track Data File Format 9.1 9.2 9.3 Screen Output on "CMPTR" Line During Computer Start-up ...... Video Installation Configuration .... "Pepper" on the RGB Image ....... Sample RGB Abnormality ... Sample Occultor Misalignment ..... 9.4 9.5 LIST OF TABLES Table # Table Title Page 6.1 6.2 MS Editor Menu Options ...... MS Quick Commands .. - iii - 1. INTRODUCTION This document describes the Real Time Cloud System, and the interim program currently being used to run it at the HELSTF test site at White Sands Missile Range. This system was developed by the Marine Physical Laboratory, Scripps Institution of Oceanography, University of California San Diego, under contract #N00014-87-C-0127, Mod 42, CLIN#2AA. The Real Time Cloud System is an automated imaging system designed to give real time assessment of the cloud field, for on-line operational support. Cloud cover is determined at approximately 1/3 degree spatial resolution, at 5-minute intervals. A determination of cloud, thin cloud, or no cloud is made for every point in the scene, and the result is presented to the user in color-coded format (white= opaque cloud, yellow=thin cloud, and blue=no cloud). The user may also input the angular coordinates of a track of interest, such as the track of a satellite or drone. This track is then superimposed on the cloud image, for visual of the scene characteristics in the immediate angular vicinity of the track. ass CC The estimated percent cloud cover, both opaque and total, is presented to the user both on the image and on the computer terminal screen. In the future, we plan to include cloud cover along the track itself in this presentation. A sample of the final result presented to the user is shown in Fig. 1.1. If desired, the user may also review the recently acquired images in a time series. Currently the derivation of the cloud results requires approximately 2 minutes (this can be made considerably faster with additional computer boards). During the 3 minutes remaining until the next grab, the user may at any time request to see the past images. The system prompts the user to determine how long an interval is desired (i.e. the last 15 minutes, the last hour, or whatever is of interest), and the cloud decision images from that interval are retrieved and displayed on the monitor in a looping format. Fig. 1.2 illustrates four images acquired at 10-minute intervals. In the normal looping, images are shown, one after the other, in the full screen format illustrated in Fig. 1.1. SXY COVER ESTIMATE 0002 1000 @09 200 100 150 WWW WW WWW 125 WA ibora WW OVA FI REGIONA SKY COVER 190 BER = bdo = 701 789 729 75 Figure 1.1 Sample RTimCid Display BRI COET ESTIMATE SRT COVEE ESTINATE 500G 2000 1000 3CMP3 500 500 200 100 100 150 150 125 125 ONA KIVIA 180 100 SKY COVER Opq = 41% Tot 52% SKY COUER Orq - 29% Tot - 39% COM BBY CODE) ESTINATE 5000 SIN COPER ESTIMATE 2008 2000 1000 500 500 200 200 100 150 150 125 125 UH INIHA SKY COUER Opq - 48% Tot - 58% SRY COUER Opa - 45% Tot 54% 75 75 Figure 1.2 Sample Loop of 4 images acquired at 10-minute intervals 2. SYSTEM HARDWARE OVERVIEW The Real Time Cloud System depends on the presence of a Whole Sky Imager (ref. Shields, 1990 and Johnson, 1989). The WSI is an automated system designed for archival of cloud field imagery at one-minute intervals. This system is a passive (i.e. non-emissive) system, which acquires calibrated multi-spectral images of the sky dome. The sky is viewed through a series of spectral and neutral density filters using a fisheye lens to acquire most of the upper hemisphere. The sensor is a fixed-gain solid state CID (charge injection device) camera. The WSI is controlled by an IBM AT-class microcomputer. This fully automated system acquires four digital images every minute, at 512x480 resolution. The WSI then archives the images on 8 mm tape, for post processing. Although a stand-alone Real Time Cloud System could be devised around these two primary components alone, i.e. the camera end and the computer end, the system at HELSTF site utilizes an additional computer, and piggy-backs off the same camera unit. That is, the video output from the sensor is sent by optical fiber to the second computer unit, where the images are digitized and processed to yield the cloud/no cloud images. This was done to take advantage of the hardware already in place, thus minimizing the additional cost of the real time unit. Thus the three components at HELSTF are the sensor, or camera unit; the primary computer or master controller, which controls the camera system, and archives data for processing at MPL; and the secondary or slave computer, which grabs the image coming over fiber and makes the cloud determinations. These components are shown schematically in Fig. 1.1. In order to achieve proper synchronization between the master and the slave computer, an additional fiber is used to transmit a timing pulse. This pulse indicates that the filter changer is in a stable configuration, and indicates which filter is . currently in place. SONY PVM 1271 Q MONITOR GE 2710 SOLID STATE VIDEO CAMERA TMI COMPUTER (IBMAT CLONE) VIDEO AUTOMATIC EQUATORIAL SOLAR OCCULTOR ASSY. IMAGE PROCESSING SUB-SYSTEM (ITI FG 100) ARCHIVAL I/O SUB-SYSTEM (SEAGATE 65 Mbyte H.D.) NORMAL WSI SYSTEM ANALOG REMOTE CONTROLLED IRIS ASSY. EXABYTE EXB - 8200 2.2 Gbyte 8 mm CATRIDGE TAPE SYSTEM ACCESSORY CONTROL PANEL REMOTE CONTROLLED OPTICAL FILTER ASSY. STOWED KEYBOARD MASTER COMPUTER INSTALLATION EXTERIOR SENSOR INSTALLATION SONY PVM 1271Q MONITOR ................................................... RS232 FIBER TMI COMPUTER (IBM/AT CLONE) VIDEO FIBER mmm... m ARCHIVAL VO IMAGE PROCESSING SUB-SYSTEM (ITI FG 100) SUB - SYSTEM (SEAGATE 65 Mbyte H.D.) ADDED UNIT FOR REAL TIME SYSTEM EXABYTE EXB - 8200 2.2 Gbyte 8 mm CATRIDGE TAPE SYSTEM STOWED KEYBOARD SLAVE COMPUTER INSTALLATION Figure 2.1. Hardware block diagram, whole sky imager system with added computer unit for real time cloud determination 3. RUNNING THE REAL TIME PROGRAM This section details how to start and use the computer program installed on the slave system. Later sections give further documentation of the internal workings of the program. As this program is further updated, changes to this section will be appropriate. 3.1 Overview The program RTIMCLD was designed to run essentially without human intervention. At start-up, there are some questions the human needs to answer, but following start-up, the program is automatic. A summary of the start-up options is shown i We also wished the human to be able to interact if desired, to request a review of recently acquired data, or to change selected operating parameters. To enable this option, the program has a number of "hot keys". That is, the program works independently unless a keyboard entry is made, in which case the program pauses to solicit further instructions. A list of the hot key options is shown in Fig. 3.2. The following sections will review how to find and start the program, how to proceed through the start-up sequence of the program, the normal response of the program in automatic mode, and the use of the hot keys. Detailed interpretation of the display on the screen will be in Section 5. It is assumed in this description that a file of track information already exists on disk. The creation and editing of this file is discussed in Section 6. 3.2 Finding and Starting the Program Turning on the Computer First the computer must be turned on. There is a surge protector at the back, which must be on, and a key on the computer body, which must be horizontal. The computer automatically goes through a sequence of operations such as accessing the hard disk. When these are completed, the system goes to subdirectory RTIMCLD. The details of this sequence are discussed in Section 9.1 FIGURE 3.1 PROGRAM START UP OPTIONS OPTIONS: NORMAL DEFAULT: nem TRACK.DAT Use the Exabyte? Enter Y or N Use a track file? Press Enter or Enter Track Filename: Change cloud thresholds? Enter o or thin cloud threshold Grab new live images? Enter G for grab, R for Retrieve, L to Loop: o o 14 MPC FIGURE 3.2 HOT KEY OPTIONS C = Change cloud threshold D = Save radiance images under name you select T = Save ratio images under name you select S = Smooth the ratio image R = Show RS232 diagnostics X = Exit the program Monitor Appearance: CMPTR Line There are several buttons on the front of the monitor. By pushing the "CMPTR" button, the user brings up the computer output on the monitor. If all has gone well, the screen should show the entry D:\RTIMCLD> meaning that the user is on the D: disk drive, in subdirectory RTIMCLD, and the system is awaiting user entry. If this is not what you see, consult the Section 9.1, the section on trouble shooting Monitor Appearance: Line A By pushing the "LINE A" button, the user should see the live video image coming in over the fiber optic. This should change several times a minute, as the filters on the camera are changed under control of the master computer. The live video should look like a slightly elliptical image of the sky. If this is not seen, one should check whether the master system is running; if the master is down, the slave system will not receive a signal. Likewise, if the fiber transmittance has degraded or failed, there can be either a dark image or no image. See Section 9.2. Monitor Appearance: RGB Pushing the "RGB" button will show the images stored on the imaging board. At this point in the program, it has not been initialized, and should normally show vertical colored stripes. If not, check Section 9.3. Initiating the Program If all is normal, return to the computer line by pushing the "CMPTR" button. The program is started by entering the command "RTIMCLD" , i.e. type the name RTIMCLD in either upper or lower case, followed by the "Enter" key. This should start the program. Green 3.3 The Start-up portion of the program General Format of Displays In the start-up portion of the program, a series of four decisions are asked of the user. For each decision, the text display first gives the explanation in lower case, inset 5 spaces, and then summarizes the question to be answered in upper case, left adjusted. Thus once one is familiar with the program, it is only necessary to read the bottom line of the screen, be left adjusted and upper case. The lower case explanatory material is included on the screen for general reference. Ier Case First Text Display Once the program is started, as in Section 3.2, the first text display to appear is that shown in Fig. 3.3. This text display first reviews the function of the program, then lists the hot key options. These will be discussed further in Section 3.5. This is followed, still on the first text display, by the exabyte use option, discussed below. 3.3.1 Exabyte Option User Options At the bottom of the first text display, the user is asked whether to save the ratios to Exabyte (see Fig. 3.3) The exabyte is the 2.2 gigabyte capacity tape drive installed in the slave computer. If the user responds with a Y, y, or yes, the ratio images will be saved on tape. (Other answers such as YES and Yes are also accepted. If a numeric answer is entered, the program will repeat the request for a Y or N answer.) The exabyte can be used if the user wishes to retain a permanent record of the data run, or if a sample is desired for shipment to MPL. There are programs at MPL which can address these tapes, however they are not overly user-friendly. The normal default for this question is to type N, followed by the enter key, to prevent saving to Exabyte. · 10. . R . OHRU OOOOOOOOOOOOOOOOOOOOONOROD. OOOROOD RORONOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO SOOOOOOOOOOOOOOOOOOOOOOO OBS Marine Physical Laboratory - Optical Systems Group Scripps Institute of Oceanography University of California, San Diego WSI - Whole Sky Imager Real Time Program Program: RTimcld Version 1.0 Function: Grabs images from incoming Video line, Performs automated composite ratio process and displays resulting sky cover images. Writes resulting images to tape. Note: Sky Cover Images will be displayed on RGB Display. If you have several hot key options available. If you press one of the following keys, without the Enter key, You will enable the listed options. C = Change cloud threshold D= Save raDiance images under name you select T= Save ratio image under name you select S = Smooth the ratio image R = Show RS232 diagnostics X = Exit the program Pressing any other key will cause the options to be shown Do you want to save the ratios to Exabyte? Y = Yes, N = No ENTER Y or N: OOOOOOOOOOOO BADONA Figure 3.3 First Text Display in RTIMCLD: Introduction and Exabyte Option The No Response If the user enters N, to indicate no save to Exabyte, the program proceeds directly to the second text display, discussed in Section 3.3.2. The Yes Response, if tape is loaded anSV If the user wishes to use the exabyte, a tape can be inserted any time prior to answering the question on tape use. It requires approximately 40 seconds for the exabyte to complete the self check. When the green light comes on (on the Exabyte), a few seconds pass and the tape drive makes one more mechanical sound. At this point the self check is complete, and the user may answer Y to allow saving to exabyte. If the user enters Y, to indicate yes, additional lines of text are displayed at the bottom of the screen, to indicate the status of the exabyte. Fig. 3.4 shows the normal sequence, which occurs when an exabyte has been loaded. In this sequence, the exabyte is tested, and an end-of-file (EOF) mark is written to tape. This sequence requires a seconds to complete. Following this, the computer brings up the second text display, discussed in the next section. The Yes Response, if no tape is loaded If the user enters Y but there is no tape in the Exabyte, an alert message is added at the bottom of the screen, as shown in Fig. 3.5. This message is rather cryptic; but when you see it, you need to insert a tape and start over. The program continues to the next text display here unless you stop it. It can be stopped by holding the "Ctrl" key on the keyboard, along with the "C" key, i.e. enter Ctrl-C. The tape can then be inserted, and the program restarted. (We need to change this in the program; it should stop and ask the user to insert a tape.) Once the user successfully disables or enables the Exabyte option, the program proceeds to the track option. O OOOOOO OOOOOOO OOOOOOOOO UUUUUUUU Marine Physical Laboratory - Optical Systems Group Scripps Institute of Oceanography University of California, San Diego WSI - Whole Sky Imager Real Time Program Program: RTimCid Version 1.0 Function: Grabs images from incoming Video line, Performs automated composite ratio process and displays resulting sky cover images. Writes resulting images to tape. Note: Sky Cover Images will be displayed on RGB Display. You have several hot key options available. If you press one of the following keys, without the Enter key, You will enable the listed options. C = Change cloud threshold D = Save raDiance images under name you select T= Save ratio image under name you select S = Smooth the ratio image R = Show RS232 diagnostics X = Exit the program Pressing any other key will cause the options to be shown. Do you want to save the ratios to Exabyte? Y = Yes, N = No ENTER Y or N: Y Now testing to see if the Exabyte Tape Drive is ready, ExaByte Tape Drive is ready. Now writing an EOF mark to the ExaByte Tape Drive. BOOOOOO POROU Figure 3.4 First Text Display after answering "Y" if there is a tape in the Exabyte ITTI DO Marine Physical Laboratory - Optical Systems Group Scripps Institute of Oceanography University of California, San Diego WSI - Whole Sky Imager Real Time Program Program: RTimCid Version 1.0 Function: Grabs images from incoming Video line, Performs automated composite ratio process and displays resulting sky cover images. Writes resulting images to tape. . Note: Sky Cover Images will be displayed on RGB Display. If you have several hot key options available. If you press one of the following keys, without the Enter key, You will enable the listed options. C =Change cloud threshold D = Save raDiance images under name you select T= Save ratio image under name you select S = Smooth the ratio image R = Show RS232 diagnostics X = Exit the program Pressing any other key will cause the options to be shown. DOVOOOOOOOOOOOO OOOOOOOOOOOOOOOOOOOO Do you want to save the ratios to Exabyte? Y = Yes, N = No OOONOR UNBO BOO ENTER Y or N: Y Now testing to see if the Exabyte Tape Drive is ready. ExaByte Tape Drive is ready. Now writing an EOF mark to the ExaByte Tape Drive. OU . . . DOI COOOOOOOOOOOOOOO OOOOOOOOOO....DOUDOU .OOOOO.OOOOOOOOOOOOO TOILUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUU WOOOOOOOOOOOOOOOOOOOOOOOOOOOO OUGOUONNOOOOOOOOOOOOOOOOOOOOO OROSO .. . . . . . . . . . . . . . BOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO OOOUUOOOO ... . .. . ..N O OO O 2 2 BO ALERT. Bad Exabyte Write Status: At 60k Byte Block #: F OOORO OOOL. Figure 3.5 First Text Display after answering "Y" if no tape is present 3.3.2 Track Option The second option is whether or not to enter a track designation. If one wishes to have the track of a satellite or drone superimposed on the final cloud image, it is necessary to have a file of the track coordinates. Section 6 discusses how to create this file. The generic "TRACK.DAT" is normally kept on disc, and can be used as a sample. The second text display, which addresses the use of the track file, is shown in Fig. 3.6. Responding with no Track file If the user does not wish to input a track file, the "Enter" key is pressed, and the program continues to the third text display. Responding with a Track file . If the name of a track file is entered, the contents of the file are shown on the screen, as shown in Fig. 3.7. At this point the program pauses a few seconds, to allow the user to briefly review the track coordinates, and then the program proceeds to the third text display. If an incorrect name is entered, the program will indicate a fault reading the file, and then proceed. (We need to change this to allow the user a second chance.) 3.3.3 Option of Changing Cloud Thresholds The third text display is shown in Fig. 3.8. The cloud thresholds have to do with the identification of clouds from the images. This is discussed more fully in Section 5.3. UN Evaluating whether to change thresholds The decision of whether or not to change cloud thresholds is based on the user's judgement of past runs. The user may decide whether the program is indicating the proper amount of cloud cover. BORANDO U DADO DON .. 000000 OBO . OOO0000 RDBORDOOR QUOOOOOOOOOOOOR OOOOOOOOOOOOOOOOOOO Please enter name of Track Data Coordinate File or press ENTER to use no track. File TRACK.DAT is a sample file. AOOOROOOGONOROGOROOOOOOOORGRONDOUDOUNDOOOONRISUONIO W&NOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO GOOOOOOOOOOOOOOOOOOOOOOOOOOOO OROOOOOOOOOOOOOOO PRESS ENTER OR ENTER TRACK FILENAME: OOOOOOOOOOOOOOOOOOOOOO Figure 3.6 Second Text Display: Addresses Track File Option OOOOOOO SORROR Please enter name of Track Data Coordinate File or press ENTER to use no track. File TRACK.DAT is a sample file. PRESS ENTER OR ENTER TRACK FILENAME: track.dat Track Coordinates Amimuth Zenith Altiude (ft) 180 ULOGU 180 180 80 23000 20000 15000 10000 8000 6000 4000 3000 2000 1000 180 200 210 220 230 60 60. 800 240 60 60 500 300 200 100 250 260 270 280 60 60 000 Figure 3.7 Second Text Display after entering track file name OO OVOOOR Do you want to change the cloud decision thresholds? Current thresholds are thin=120, thick=140. Type O if thresholds are Ok, or enter new thresholds ENTER O or THIN CLD THRESHOLD: OUDODOOOOOOOOOOOOOOOO OOOOOOOOOOOOOOOO JOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO TORNOGORROTONDON AURORTODON UNG KROBONOROGORONGOOOOOOOOOOOOOOOOOOOOOOOOO OHOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO IR IND Figure 3.8 Third Text Display: Addresses Cloud Threshold Option This judgement can be made on the basis of the Line A input video, since the human is an excellent (but unfortunately not automated or consistent) image processor. In general, once the threshold values are chosen, as discussed in Section 5.3, the same thresholds may be used each time. The default values are 120 for the thin threshold and 140 for the thick threshold. Which way to change thresholds More specifically, the thin cloud threshold is used to estimate whether a given location in the image is sky or thin cloud. If on recent runs the program has been indicating too much blue sky, the thin cloud threshold should be lowered from the previously used value. The thick cloud threshold is used to distinguish thin cloud from opaque cloud. If the program has been indicating too little opaque cloud, the thick cloud threshold should be lowered from the previously used value. Any time the desired values are not the default values of 120, 140, they must be entered. This is discussed in further detail in Sections 5.3 and 9.7. Method of changing thresholds If one wishes to leave the thresholds at the default value, one enters "O", followed by the "Enter" key, and the program proceeds to the fourth text display. If one wishes to change the thresholds, the thin cloud threshold should be entered. The program will then prompt the user for the thick cloud threshold, as shown in Fig. 3.9, and then proceed directly to the fourth text display. If one accidently enters both the thin and thick thresholds in one line, the program will only read the first, and then ask for the thick thresholds. Thus the program recovers properly in this case. If one enters a non-numeric response, however, the program will halt and it will be necessary to restart (we need to change this). 3.3.4 Options for use of Program The fourth text display is shown in Fig. 3.10. At this point, the user has three options: grab new imagery from the live video, retrieve a sample set of radiances from disk, or loop through saved ratio images. -19- GOOOOOOO COCCO Do you want to change the cloud decision thresholds? Current thresholds are thin=120, thick=140. Type O if thresholds are Ok, or enter new thresholds ENTER 0 or THIN CLD THRESHOLD: 80 ENTER THK CLD THRESHOLD: 90 NOT OOOOOOOOOOOOOOOOOOOOOOOOOOOROOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO O ODOLOOOOOOOOOOOOOOOOOOOO OIDLOOOOOOOOOO OOOOOOOOUUDIO P000OOOO UUUUUUUUUUUUUUUUUTITETITTTTT WOOOO DOOOOOOOOO OOOOOOOOOOOOOOOOOOOOOOOOOOOOO WOODPOROOOOOOOOOOOOOOOOOOOO...OOOOOOOOOOOOOOOOOO OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO TERRON DODOU OSOVOOOOOOOOOOOOOOOOOOOOO ODOLOOOOOOOOOOOOOOOOOOOOOOOOO 000 HO Figure 3.9 Third Text Display after entering new cloud thresholds O OR DODOCO00000000000OO0OOOOOOOOO 00 BOOGOO OUDOUDO Do you want to grab images from live video, retrieve sample radiance files from disk, or loop through a previously acquired set of ratios. PRKROGORO #OGONIO ENTER G for Grab, R for Retrieve, or L to loop: 1 TA OOOOOOOO Figure 3.10 Fourth Text Display: Addresses Program Mode Decision Option The Grab Option The normal default option is to grab images from live video. This will start the program running in automatic mode, grabbing images every 5 minutes, and presenting the cloud results. When this option is chosen, the screen will show the resulting percent cloud cover for as long as the program is run in automatic mode. (The automatic mode is described in Section 3.4.) The Retrieve Option The second option is to retrieve radiance images from disk. This is usually done only for test purposes. If the user has previously saved 4 radiance images, as described in nese may be retrieved. Fig. 3.11 shows the response of the program if the user requests "R" for Retrieve. The user is asked for a 7 character file name characterizing the radiance files. The files are retrieved and brought in on the imaging board, where they may be viewed by pushing the "RGB" button on the monitor. Having retrieved the radiances, the program asks the user for an estimate of the occultor angle and the neutral density filter used. The occultor angle is 90 when the occultor is at the top, 0 on the right side of the image at the Eastern horizon, and 180 on the left side of the image at the Western horizon. The ND value should for now be 1. The radiance images are then ratioed and presented as if they had just been grabbed, as discussed in Section 3.4.2. Following this, the program returns to the fourth screen. The Loop Option The third option regarding use of the program (as shown in Fig 3.10) is to loop. With this option, the user may bring in ratio images acquired previously, and display them on RGB. As shown in Fig. 3.12, the user is asked which file name to bring in, and then asked for the starting and ending file number. (Section 7 discusses the format of these file names.) Once the file names and numbers are entered, previously saved ratios, acquired at 5 minute intervals, are brought up on the screen at approximately 1 second intervals. This allows one to view the clouds acquired at an earlier time, and also enables easy viewing of the cloud motion. This looping continues until the user enters L (this time without the enter - 22 - OOOOOOOOOOOOOOOOOOOOOOOOOOO OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO OOOOOOOOOOOOOOOOOOOOOOOOO LOOOOOOOOOOOOOOOOOOO WOOOOOOOOOOOOOOO OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO OOOOOOOOOOOOOOOOOOONE BOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO OOOOOOOOOOOOOOOOOOOOOOOOOOO . .. .... .... ..NOOOOOOOOOOOOOOOOOO OOH... ... .. ....DOR BOOOOOOOOOOOOOOOOOOOOOOO OMOGODOROROODSOOOOOOO BUTI DORSODUROOVINUD .. OWO000 . ..... .... OOOOOOOOOOO OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO STOROVOND... OOOOOOOOOOOOOOOOOOOO CODUODU Switch to RGB for status and imagery. Cloud Cover numeric results will be displayed here. To retrieve radiances from disk, enter the name of a previously saved radiance file set. ENTER FILE SET NAME (7 char): COL0116 Figure 3.11 Response following Fourth Text Display if user requests "R" for Retrieve INPUT NEUTRAL DENSITY FILTER USED: 1 INPUT OCCULTOR ANGLE: 130 ORGTR OOOOOO WUWUNOOOO NUORODOOOOOO OUUONO.OCO.UU. UWVORUWOWUUUUUUUUUUUUUUUUUUUUUUUWSOV OWODOWODOWOWOWOWODOW RUNDOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO BU OUCO. . O BOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO COLOSOOOOOOOOOOOO OOOOOOOOOOO BRODOWROOONGGOSOBISONOB DOBRODOUDO0OOOOOOO OOOOOOOOOOO OOOOOO OBOOOOOOOOOOO OOS PIDO 20 . . . . . RODOS OIO ODBOR PUCUNONOODS OOOOOOOOO SONORO 0000 OBOBOROUS OOOOOOOOOOOO Do you want to grab images from live video, retrieve sample radiance files from disk, or loop through a previously acquired set of ratios. BOOOOOOOOOOOOOOOOOOOOOOO TOR ENTER G for Grab, R for Retrieve, or L to loop: L GOOOOOOOOOOOOOOOOOOOO OOOOOOOOOO You will be asked to enter a 6 character file name, followed by the starting and ending number you want. For example, if you renamed yesterday's CLOUDS files OC1189, and you want to loop through files 14 through 29, respond with OC1189, then 14, then 29. D OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOORNEO DOPORU.O.OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO OOOOOOOOOOOOOOOOOOOOOONOBOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO.000. OOOOOOOOOOOOOOOOOOOO 0000OOOOO GOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO DORO OPOSOBNOORDONOSOBOBOROOOOO OTRNOO ENTER 6 Char File name: BAR27A ENTER Starting file number: 1 ODREDIONISIERINORODRIDGEREEDERO ENTER Ending file number: 13 DO0OOOOOOOO 300000OOOOOOO OOOOOOOOOOOOO You can exit the loop at any time by entering the letter without pressing the enter key. OOOOOOOOOOOOOOOOOOOOOOOO LOOOOOOOOOOOOOOOO BONOBONGBONOBOWODOCOLOURBO 000000 HONOUROBONSORSODORO NOORWOODWOUD DO . . . OOOOOOO OBUONIO . OOOOOOOOOO OOOOOOO OOOOOOOOOO NOBGGU . . . D . NONOOONOOR BUCO OBOD.O.O. COCOCCC ODDODDODOVODSUMOOOOOOOO ODOOPS OOOOOOO CCCCC UHRDINOSOUNDOURVOORSOUIEREN OO OROLO OOOOOOOOOO Figure 3.12 Fourth Text Display, after user requests "L" for Loop key), at which point the program returns to the fourth screen. The procedures for saving the ratio images for looping are discussed in Section 7. Options on completion of Retrieve or Loop Option After completing either the Retrieve or Loop option, the program returns to the fourth text display (Fig. 3.10). At this point, the user may then proceed with automated operation if desired, by entering G for Grab. If the user chooses to end the program at this point or at any other time in the pre-start sequence discussed in Section 3.3, a Ctrl-C may be used. That is, type the "Ctrl" key and the "C" key simultaneously. 3.3.5 When to use the Enter Key We should perhaps note that Ctrl key options, such as Ctrl-C to interrupt the program, do not use the Enter key. Similarly, hot key entries do not use the Enter key. The only hot key use described so far, is the use of L to exit the looping. Normal entries, as described in this section, require the Enter key at the end of a line of entry. A good rule of thumb is that if the computer is waiting for you to make a response, it is expecting a normal entry with the Enter key. If the computer is proceeding on its own, i.e. not waiting, and you use a key to interrupt the processing, then this is using a hot key, and the Enter key should not be used. 3.4 Program Sequence in Automated Mode Once one has completed the start-up portion of the program by addressing the four user options described in Section 3.3, the program will proceed in automatic mode until interrupted by a hot key, as described in Section 3.5. Before describing the steps used by the program, it may be helpful to discuss the three data lines available on the monitor, and how they differ. 3.4.1 Available Data Lines on the Monitor There are three input data lines which may be viewed on the monitor. The desired one is selected by pressing the appropriate button at the bottom of the monitor screen. - 25 - "Line A" Data Line The first line is Line A, which shows the live video coming in over fiber optic. This will show raw imagery, changing several times per minute as the camera is changed by the master computer. The normal operating sequence of this imagery is as follows: Spectral filter sequence: All done with the ND filter selected on the previous flux control check. Spectral 1: Blue, looks fairly bright, low contrast. Spectral 2: Red, also fairly bright but more contrast. This image will generally have darker sky but brighter clouds than spectral 1. Spectral 3: Blue + .5 log trim. This will be low contrast, like spectral 1, but much darker. Spectral 4: Red +.5 log trim. This will be higher contrast, like spectral 2, but much darker. Flux Control sequence: All done in Spectral 2. This automatic sequence may repeat more than once. ND1: No ND filter. If this is the selected filter, as is usually the case, this will be the same filter combination as the Spectral 2 grab above. If not, it will be brighter than Sp. 2 above. .3 log filter. Darker than ND 1 .7 log filter. Darker. 1.0 log filter. Darkest. ND2: ND3: ND4: In this sequence, the spectral set contains the images of use to the real time system. Fig. 3.13 shows the four images acquired during the spectral grab. When they are seen on Line A, they are seen one image at a time, without the labels. TE01A+24 TEMA 24 VZO- Spectral 1 (blue) Spectral 2 (red) TEMP 24 இது மது wo Spectral 3 (blue + trim) Spectral 4 (red + trim) Figure 3.13 Sample Raw Data Images The flux control set is used by the master computer to determine the optimal combination of neutral density filter and aperture setting for control of the flux level impinging on the imager chip. In general the user does not need to be concerned with the image sequence on Line A. This sequence continues whether the real time program is running or not, as long as the fiber optic and the master system are operational. "CMPTR" Data Line The second input data line available to the user is the computer line selected by pressing the "CMPTR" button on the monitor. This is the data line used for program start- up in Section 3.3. Once in automated mode, the derived percent cloud cover is added to the end of the text on the screen after each 5-minute grab. If one does not use the hot keys, the screen will fill up with approximately 30 such entries, and one can read the change in cloud cover over the associated 2-3 hour period. If hot keys are used, the text associated with their use is also shown on this text display. One of the changes we wish to make is to return to a clean listing of cloud cover, once the hot key interaction is complete. "RGB" Data Line The third and most useful input data line is the RGB line. This display shows the images stored at any given moment on the imaging board. At first one sees the processing of the images, as discussed below, and then one sees the final cloud decision image. There is also a line of text at the bottom left of this display, written on by Program RTIMCLD, indicating what the program is currently doing. (This status cue on the RGB image display is not a normal feature of other programs.) Line to Select during Automated Processing When the program is running in automatic mode, the user should normally select the RGB line, since this will display the cloud decision image. However, this means that all the image processing will also be displayed to the user. A description of the sequence of operations as seen on the RGB line may therefore be helpful. The RGB sequence is described in Section 3.4.2, and illustrated in Fig. 3.14. Section 4.2 gives a more complete description of the reasons for each of these steps. -28- Await Sync Grab Image = Raw Radiance Image N Finished 4 filters Y Linearity Correction (all 4 images) Compute Red/Blue Ratio = Ratio Image Apply Color = Cloud Decision Image Count Pixels for % Cover 5 Min Complete Figure 3.14 Sequence of Operations seen on RGB Line 3.4.2 Sequence of Operations shown on RGB Screen When the user completes the start-up sequence, the next step is normally to change to RGB screen. This should be black, except for the indication "AWAITING SYNC", in red at the lower left. Once the master computer reaches the spectral sequence, the slave computer should begin grabbing images. If it does not, then this indicates a problem with the Sync. This is further discussed in Section 9, Trouble Shooting. Initial Grabs If sync is coming through normally, the RGB channel will display the result of four grabs (one for each of the four spectral filters, see Fig. 3.13), at approximately 2 second intervals. These grabs will appear as four raw radiance images similar to those seen on Line A. Once the grab sequence is completed, processing begins. The processing takes a total of about 2 minutes. Linearity Correction The first processing step is correcting for non-linearity of the camera sensor. This takes about 5 seconds; the user may notice the images jump horizontally during this sequence (this is normal). Ratio Computation The program then begins to compute the ratio of the red image to the blue image. This ratio computation includes the use of calibration factors which correct for differences between the various spectral filter passbands. Also, as part of this process, a pixel by pixel decision is made of which is the best filter pair to use: 1 and 2, or 3 and 4. Filters 1 and 2 will be used in the darker parts of the image, and 3 and 4 will be used in those regions which are offscale bright in filter 1 or 2. During this ratio computation, the status cue at the bottom left of the RGB screen should say "Computing Ratio". This step is quite slow, requiring about 50 seconds with a 286 CPU board. The use of a 386 CPU board would shorten this time to around 30 seconds. If speed becomes more critical, the use of a pipeline processor speeds the -30 computation time to about 8 seconds, but requires use of different code, which is currently in use in the standard archived data processing programs at MPL. Color Coding to yield a Cloud Decision Image Once the ratio has been derived, the image is immediately color coded to display a cloud decision image. This scheme is based on a simple thresholding of the ratio image. Regions which are determined to be cloud, i.e. those with ratios higher than the thick cloud threshold entered as in Section 3.3.3, are colored white. Those between the two cloud thresholds are colored yellow, and those below the thin cloud threshold, i.e. those estimated to be clear sky, are colored blue. The format of this cloud display is described in more detail in Section 5. Determination of Percent Cloud Cover While the cloud image is displayed, the program makes a determination of percent cloud cover, both total and opaque. During this step, the status cue in the left corner indicates "Computing Cover". When the cover has been computed, it is displayed near the lower left corner, above the status cue The display of the cloud image is illustrated in Fig. 3.15. Wait Period At this point, the processing is complete, and the program waits for the next time to grab. Normally, images are grabbed by the slave only on five minute marks, i.e. 1200, 1205, etc. However when the program is first started, the next available minute is grabbed. (The master grabs every minute.) Thus, all grabs by the real time system are timed five minutes apart except for the first two. This 5-minute increment is fixed in the code, however it could easily be changed to a different increment. We Looping during the Wait Period While the program is waiting for the next 5-minute mark, one may use hot keys to bring in a display of recently acquired images, in a loop (see Fig. 1.2). The status cue in the lower left indicates this by the phrase "OK TO LOOP". The text also gives a further indication that looping may begin. Up until this point, the status cues on the RGB screen -31- 2000 We 1000 500 200 100 1150 125 WWW W WWW 180 WM We SKY COVER Opa = 47% Tot = 54% 75 Figure 3.15 Cloud Decision Image Display have been given in red/orange print. When it is Ok to loop, the cue is given in green. Thus the user may simply glance at the RGB screen. If there is a "green light", it is Ok to loop. The "red light" on the cue means to wait. Looping is initiated, if desired, through use of a hot key described in Section 3.5.8. Starting the Next Grab Sequence If the user makes no hot key entries, then the program will start with a fresh grab on the next 5 minute mark, and the above steps will be repeated. I should note that if the slave and master clock are not correctly synchronized, the slave will begin a wait for the next sync pulse from the master on the five minute mark. If the slave is not timed correctly with the master, it may then have to wait for up to 1 minute, for the master to reach its one minute mark, when it begins to grab. The slave clock is normally reset using the time sent with this sync pulse, so this mismatch should not normally occur, however the time will not be updated if the time signal comes through garbled. For more details, see Section 4.3. Terminating the Program The system will continue to run automatically, unless the system fails or the user terminates the program. The program is terminated through use of the exit hot key, as described in the next section. 3.5 Use of Hot Keys A hot key is one that is used to interrupt the normal processing of the program. Once the program is into the automated mode, as described in Section 3.4, the program checks frequently to determine if any keys on the keyboard have been hit. If so, it stops and requests further instructions. These checks are made at several steps in the processing, i.e. before applying linearity corrections, before starting the ratio, etc. Checks are also made continuously during the wait interval. The program does not check within a given computation step, however. For example, it does not check during the middle of the ratio computation. Thus the response to a hot key entry may not be immediate. - 33 - The hot key options used during the processing are listed below. An additional hot key used later in the program is discussed in Section 3.5.8. C = Change cloud threshold D = Save raDiance images under name you select T = Save ratio images under name you select S = Smooth the ratio image R = Show RS232 diagnostics X = Exit the program If any other key is pressed, the program will stop to query the user with regard to what was intended. Currently, the program will hang until some response is made; we plan to add a timer loop to this, to continue after a short interval if no response is made. 3.5.1 "C" Hot key The "C" hot key allows one to change the cloud thresholds entered as described in Section 3.3.3. When this key is hit, the screen shows the text illustrated in Fig. 3.8, i.e. the same cloud threshold query as in the start-up of the program. This allows one to experiment with different thresholds, if desired. This option remains enabled until disabled by a second use of the "C" hot key. Thus the program will stop once each cycle, to ask if you wish to change thresholds, until you disable this option. 3.5.2 "D" Hot key The "D" hot key allows one to save the four radiance images, i.e. the initial images grabbed with the four spectral filters. This part of the program uses a 7 character event name entered by the user, such as TEST001. Then the program names the four image files TEST0011.DAT, TEST0012.DAT, TEST0013.DAT, and TEST0014.DAT, for the four spectral filters. When the "D" key is entered, the program will print the following to the computer screen: If you wish to save the radiances, enter the event name (7 char). Otherwise press ENTER. 34- ENTER EVENT NAME: Thus if one chooses not to save the images in question, one presses the Enter key; otherwise one types an event name, followed by the Enter key. The four files will then be saved on disc, where they can later be retrieved with the retrieve option discussed in Section 3.3.4. Note that since the program is waiting for a response to event name, the Enter key must be used after the event name is typed. This hot key option remains enabled until disabled by hitting the "D" hot key again. 3.5.3 "T" Hot key The "T" hot key allows one to save the ratios under a filename of choice. When this key is hit, the program will print the following to the computer screen: If you wish to save the ratio, enter the file name (up to 30 characters). Otherwise press ENTER. ENTER RATIO FILE NAME: Even when this option is not used, every ratio file is saved to disc automatically, as described in Section 3.5.8. However, the file name is such that it is sometimes difficult to retrieve a user-selected image. The "T" hot key allows the user to save the ratio under a more easily remembered file name, for later viewing. Although there are a number of programs at MPL for interactive analysis of an image, these programs are not user friendly, and have not been installed on the real time system at this time. This option is primarily for use by MPL in testing the system. This option remains enabled until disabled by hitting the "T" hot key again. If this option is used, the text on the RGB screen will indicate "Saving Image" during this step. 3.5.4 "S" Hot key The "S" hot key causes the program to smooth the ratio image on subsequent grabs, until disabled by hitting the "S" key again. The smoothing option serves to lessen the effects of random electronic noise on the signal, however it is quite slow, requiring about -35- 30 seconds. The random variance in the ratio image is most extreme when the input radiance signals are low. The noise level also depends on the camera. As the cameras become older, they become significantly more noisy. After about a year, they must be brought in-house for repair. In general, the noise has little effect on the computed cloud cover, however it can be visually disturbing. The default condition is no smoothing, but the user can request smoothing if it is considered worth the time. If the system is later upgraded to use a pipeline processor, the smoothing will become quite fast, and will probably become the normal default. If smoothing is used, the status cue on the RGB screen will indicate "Smoothing Image" during this step. 3.5.5 "R" Hot key When the "R" hot key has been used, the program will print diagnostic information regarding the RS232 transmission to the computer screen. RS232 is the format used for transmitting the sync signal over a fiber optic line to the slave system. This sync signal includes encoded values of filter number, occultor angle, and time. If there is a problem with the sync, this option may be used to help diagnose the problem. This is further discussed in Section 8.4. 3.5.6 "X" Hot key The "X" hot key allows a clean exit from the program, without the use of Ctrl-C. The Ctrl-C could be used, however during the automated part of the program, the system is often tied up on the imaging board, such as during the ratio computation, and will not respond to Ctrl-C. Since the program checks for hot key use frequently, use of the X is usually the fastest way to exit. When the X key is used, program responds with the following: Do you wish to exit the program? Type EXIT to exit, or NO to continue Thus the program demands that the user verify that he really wishes to exit. This is to protect against inadvertently hitting the X key and stopping the run. Although the program -36 indicates that "NO" should be entered to cancel the exit, any response other than the word "exit" will cause the program to continue. 3.5.7 Use of other hot keys If any other key is hit during the automated portion of the program, the program will stop to query the user in the following format: Please type C to change color flag, D to change Save RaDiance flag, T to change Save RaTio flag, S to change Smooth flag, R to show RS232 diagnostics, X to exit program, or press ENTER to change nothing. If the user intended to hit a hot key, but forgot which one to use, this option allows him to determine the one to use. On the other hand, if the user accidently hit a key, this allows the user to instruct the program to continue. As mentioned earlier, we plan to add a timing loop to this instruction, in case the key is hit without the knowledge of anyone. 3.5.8 Use of the "L" hot key for looping The above hot keys may be entered at any time after the start-up is completed except when the program is looping. There is an additional hot key, the "L" used for looping, which may be used only when the program is in the wait state. That is, once the green light comes on, indicating "OK TO LOOP", then the L key may be used to start looping, and then again to stop looping. If the L key is used at any other time, the program indicates that the user must wait until the "OK TO LOOP" sign is on the RGB screen. If the L key is used when it is Ok to loop, the program prints the following on the computer screen: Enter the number of hours and minutes you wish to review, in format HR MN -37- ENTER HR MN: If the user wishes to view the last hour, the numbers 01 00 are entered. The images from the last hour will be brought in and looped at approximately 1 second intervals. If the user enters a time longer than the program has been operating, the program will start the loop with the first image. Also, only 99 images, or 8 hours 15 minutes, may be saved. The most recent 99 images will be on disc, so if the system has run for more than about 8 hours, those at the beginning will be lost, unless they have been saved to Exabyte. Each day, the program overwrites the files used on the previous day, unless the images are saved by a separate program, described in Section 7. This is to avoid filling the disc. It is always important for the user to ensure that at least 25 Mbytes of disc space are available to allow space for these files. In the next version of the program, we expect to have the program alert the user if this is not the case. 3.6 Summary of Program RTIMCLD use In summary, the program RTIMCLD begins with a series of four user decisions. These four decisions summarized in Fig. 3.1, are: 1) Do you want to save the ratios to Exabyte? Y = Yes, N = No ENTER Y or N: (default = N) 2) Please enter name of Track Data Coordinate File or press ENTER to use no track. File TRACK.DAT is a sample file. PRESS ENTER OR ENTER TRACK FILENAME: (default = file you've entered) 3) Do you want to change the cloud decision thresholds? Current thresholds are thin=120, thick=140. Type 0 if thresholds are Ok, or enter new thresholds ENTER 0 or THIN CLD THRESHOLD: (default = 0) -38- 4) Do you want to grab images from live video, retrieve sample radiance files from disk, or loop through a previously acquired set of ratios. ENTER G for Grab, R for Retrieve, or L to loop: (default = G) The program then proceeds to grab images, apply calibration corrections, compute ratio images, color them to yield cloud images, and present percent cloud cover. During this portion of the automated program sequence, the user may use several hot keys, summarized in Fig. 3.2, to change various processing parameters. The hot key message from the program is printed below. You have several hot key options available. If you press one of the following keys, without the Enter key, You will enable the listed options. C = Change cloud threshold D= Save raDiance images under name you select T = Save raTio image under name you select S = Smooth the ratio image R = Show RS232 diagnostics X = Exit the program Pressing any other key will cause the options to be shown. Finally, when the computations are complete, the user may use the L or Loop hot key to bring in past images If in the initial start-up, the user chooses Retrieve or Loop, rather than Grab, images from previous runs may be reviewed. The next section discusses the interpretation of the cloud decision display. -39- 4. REAL TIME PROGRAM STRUCTURE AND FUNCTION This section gives more details on the function of the real time program. Section 4.1 gives an overview of the program logic. Section 4.2 discusses how the cloud image is generated. And Section 4.3 gives more details regarding the timing of the program with respect to the master computer. 4.1 Main Functions of the Program Program RTIMCLD is designed to grab images coming in over optical fiber in video format, and process them to yield, in near-real time, a display of the cloud field spatial and temporal characteristics. The in-coming images, acquired with a fisheye lens and supporting relay optics and filters, represent most of the upper hemisphere. A determination is made at each pixel location, of whether that pixel is estimated to be clear, thin cloud, or opaque cloud. The resulting image is stored on the imaging board and hard disk, and displayed on the RGB line. This cloud determination is made at 5 minute intervals. The history of the cloud field changes may be displayed by bringing in the previously acquired images in a display loop. Determine User Inputs Figure 4.1 is a conceptual flowchart of the logic of the program. The steps in this flow chart are described briefly in the paragraphs below. The program first determines the user inputs, such as track to use (see Section 3). The user then chooses between three modes of use: grab, retrieve, or loop. The normal mode is grab. Wait for the Sync Signal In the grab mode, the program next waits for a signal to come in over fiber from the master system, indicating it is time to grab. This timing is further discusses in Section 4.3. This signal serves as a synchronization pulse, in that it synchronizes the slave computer with the master computer and camera. The slave computer decodes this sync pulse, to determine whether it is adequate for interpretation. If not, it continues to wait for a valid sync pulse. When a valid sync pulse - 40 - Prestart Get user input on track, exabyte, etc. Input Radiance filenames from a previous run Grab, Retrieve or Loop ? Input ratio filenames from a previous run Read Radiances Bring in first or next image Wait for Sync Compute Cloud image Decode Sync Hit L key to stop Compute % cover Good Sync go to Grab images Compute cld image & cover go to 5 min over Loop on recent time series input period to loop bring in next image 5 min over User ends loop plu go to 5 min over Figure 4.1 Program RTIMCLD Conceptual Flowchart is received, the frame grabber grabs and saves an image from the incoming video line. Once grabs have been made in all four filters, the program continues to the next step. Process Image and Wait for Next Grab The next step is processing of the radiance images to yield a cloud image. This process is discussed in Section 4.2. On completion of the image processing, the system waits for the next 5 minute increment, at which point it starts checking for a sync pulse again. ed During this wait increment, the user may display a recent time series, if desired. The program continually checks to see if the 5-minute interval is over, or if the user wishes to display the recent images in a loop. If a loop is requested, the looping continues until the time is up or the user ends the looping. If the user ends the looping, and there is still time left, a loop may be started again. Other Use Options As shown in Fig. 4.1, there are two options in addition to the main grab option. If the retrieve option is chosen, the user can retrieve radiance images stored previously, and have them processed to yield a cloud image. If the loop option is chosen, the program brings in cloud images from a previous runs, for display in the looping mode. The use of the hot keys is not shown in the flow chart. The program checks for the use of a hot key at many points in the program. The hot key response is already explained in Section 3.5. 4.2 Deriving the Cloud Decision Image Probably the most significant step in the flowchart in Fig. 4.1 is the computation of the cloud image and percent cloud cover from the radiance images. This is a fairly complex process, which is illustrated conceptually in Fig. 4.2. - 42 - Radiances Spectral 1-4 Apply Linearity Correction First or next pixel: Apply size correction dark bright bright Filters 1 & 2 onscale Filters 3 & 4 onscale von scale von scale ratio = 0 (No Data) ratio = 2/1 ratio ratio 4/3 ratio ratio = 149 (offscale) correct for 1 & 2 calib correct for 3 & 4 calib All pixels done Y = Ratio image done color image = cloud image superimpose track N increment clear count pixel ratio > thresh increment cloud count All pixels done % cloud = cloud count/cloud & clear Done Figure 4.2 Cloud Decision Image Computation Linearity Correction The raw data are illustrated in Fig. 3.13. The first step in processing these raw data is the linearity correction. In general, the camera response is nearly, but not quite, linear, that is, the output signal is nearly linearly related to the input radiance. The response is measured carefully at MPL as a function of input radiance, and a correction determined. In addition, the video signal at the output end of the fiber is somewhat distorted with respect to the input video signal. This non-linearity is measured in the field, with a series of measurements at the master and slave end. CASUICI The two sets of measurements, i.e., camera linearity and fiber/transmitter/receiver linearity, are combined to yield a linearity correction. This is applied to the raw image through use of the input look up table (LUT) on the image board. Assuming no changes in camera relative response or fiber behavior, the corrected signal at each pixel is linearly related to the input radiance. Size Correction The next set of processing steps is applied to each pixel location individually. First, a size correction is made. This corrects for a slight difference in the image size in the blue vs red images, resulting from the use of interference filters in the optical path. VS Ratio Computation Next the program determines whether the filter 1 and 2 signals are onscale. If either is offscale dark, the ratio is given a value of 0, which is treated as no data. If they are onscale, the 2/1 ratio is computed, with appropriate corrections for the differences in camera sensitivity and filter response in the blue and red. (This correction is based on absolute calibrations acquired at MPL prior to fielding the system.) If filter 1 or 2 are offscale bright, then the program checks filters 3 and 4. These will normally be onscale, when filter 1 or 2 are somewhat offscale. In this case, the 4/3 ratio is determined, again with corrections for the camera sensitivity and filter response. If filter 3 or 4 are offscale bright, then the ratio is given a value of 149, which may be treated as either cloud or no data. (In the next version, I would like to truncate the ratios at a higher value; probably 199.) - 44 - Once these steps have been completed for all pixels, the result is a ratio image of the full sky. It is a composite ratio, in that it has used the filter 1 and 2 data in the darker regions of the sky, and the filter 3 and 4 data in the brighter regions of the sky. If the calibrations are perfect, a ratio of 1.0 corresponds to a digital ratio of 128. (The calibration is not yet perfect, for a number of reasons; we are working toward better calibrations, for example by getting our source calibrations updated.) Generating Cloud Display The current cloud algorithm, which converts this ratio to a cloud image, is a simple thresholding scheme. If the ratio is greater than the thick cloud threshold, it is estimated to be opaque cloud. If it is between the two cloud thresholds, it is estimated to be thin cloud. And if it is less than the thin cloud threshold, it is estimated to be clear sky. In the real time program, the cloud result is displayed for the user by color coding the ratio image. Ratios are colored blue, yellow, or white for clear, thin cloud, and opaque cloud. The "no data" pixels are black. The colors are programmed to vary in brightness, depending on the value of the ratio relative to the threshold. The cloud color ranges from grey, when the ratio is just above the threshold, up to a bright white. The sky color ranges from dark blue, when the ratio is very low, to bright blue near the threshold. (The hue and saturation are fixed; only the intensity varies.) These colors are achieved through use of an output look up table on the image board. These LUT's assign given brightnesses to the red, green, and blue output depending on the ratio image brightness. The assigned color brightnesses and resulting perceived colors are illustrated in Fig. 4.3. This variation in color was done for two reasons: the resulting display is more pleasing and makes more sense to the user, since the cloud and sky display look somewhat more like the real sky; and poor choices of threshold are made more readily apparent to the user. For example, if the threshold is much too high, and clouds are being identified as clear, there will be portions of the blue region which are brighter blue and are shaped like clouds. In this case, the user can, with experience, recognize that these anomalous bright blue regions should be identified as clouds, and decrease the threshold as required. .45 - T1 T: [1] T2 RED LUT OUTPUT GREEN LUT OUTPUT ттттт 50 100 150 50 100 150 RATIO VALUE RATIO VALUE T1 T2 ] T1] T2 BLUE LUT OUTPUT RESULTING COLOR 300.00 250.00 200. 150.00 100.00 50.00 ттттт 0.00 ATI TTTT 50.00 100.00 50 100 150 0.00 150.00 RATIO VALUE RATIO VALUE FIG. 4.3 FALSE COLOR USED ON CLOUD IMAGE T 1 = THIN CLOUD THRESHOLD T2 = THICK CLOUD THRESHOLD Computing Cloud Cover Once the ratio image is colored to yield a color display interpretable by the user, it is still necessary to numerically threshold the ratios in order to compute cloud cover. The ratios for each pixel are compared with the threshold, and counted to determine percent cloud cover, both opaque and total (thin plus opaque). This completes the cloud computation. 4.3 Timing and Format of the RS232 Signal A The timing of the slave with respect to the master system is crucial, because the slave must grab an image when the filter on the camera is in the correct position. The master goes through a sequence of filter positions, as described in Section 3.4.1 ("Line A" Data Line section). This sequence is repeated every minute. During this sequence, the spectral filter wheel goes through the four spectral filter positions, and it is necessary to grab an image in each position. Master Time Sequence The timing is roughly as follows. The filter changer starts to move, taking close to a second to change to the next filter. Once the master senses that the next position is reached, it pauses 250 milliseconds, and checks again to be certain that the filter changer is mechanically in stable configuration. At this point, the master sends a signal to the slave over optical fiber, in RS232 format. There is then a 165 millisecond delay, to allow for transmittal time. The master then proceeds to make its own independent grab, checks the state of the system (i.e., time, temperature, current spectral and neutral density position, and current aperture and occultor values). These values are embedded in the image, and also an image label is created. This sequence takes approximately a second or less to complete. The master then moves the filter changer to the next hole. Once all four filters are complete, the master program waits two seconds, then sends a header line with a variety of embedded information. This is followed by a 330 millisecond delay. - 47 - Slave Time Sequence During the second when the filter changer is in position, the slave system must receive the sync signal, respond to it, make its own grab, and prepare to receive the next sync signal. Thus the sync signal is a necessary and required part of the hardware package, to ensure that grabs made by the slave system occur during the second or less that the filter changer is in the stable and correct configuration. Once all four filters have been completed, the slave waits for the header line, then decodes it. Sync and Header Format The signal from the master consists of two types of lines. First is the sync, consisting of a line of 128 integers representing the current filter position, i.e., a set of 128 1's, 2's, 3's, or 4's. This is the most critical line, however the slave only requires that a few of the characters come through correctly. A line is sent for each of the four spectral filters, when they are in position. The header line, which follows the four sync lines, is a line of identifying information. This information is in the following format. 0123456789012345678901234567890123456789012345678901234567890123456789 MPL QD #1 LONG 106DEG 22MIN W LAT 32DEG 18MIN N DATE=21/APR/90 TIME 7 8 0123456789012345678901234567890123456789012345678901234567 =01:00:04BIRIS=000 OCCL=167 ND=0 SP=0 116S 1V6H In the above, the first 2 lines indicate column number, 0 through 69. The next line is the contents at these column locations; thus quadrant number, longitude and latitude, and time are passed to the slave unit. The next three lines indicate column numbers 70 through 127. In these columns, time, iris and occultor, neutral density and spectral filters, and software and hardware versions are passed. Although this header contains information which is not required by the slave unit, such as latitude and longitude (which may be assumed constant), this format was used to remain - 48 - consistent with the header stored on the normal master images. The information required by the slave unit, i.e., the time and camera settings such as iris, are included in the information which is transmitted. t If time is received cleanly, it is used to update the slave time (with an appropriate correction for the delay). The master unit is normally run on WWV, using a radio clock to update the program time as well as BIOS time every minute. If the clock or serial port is inoperable, the master uses BIOS time. This time, along with a "W" or "B" indication, is sent to the slave. If the slave receives it correctly, it updates program time and BIOS; otherwise it runs on BIOS. The occultor value is also important, as it is used in computing a mask to cover the occultor in the image. If the occultor value is not read cleanly, the expected occultor position will be computed on the basis of the current time. Neutral density is used in determining the calibration constants; if it is not received cleanly, a default neutral density=1 is assumed. 5. INTERPRETATION OF THE CLOUD DECISION DISPLAY As described in Section 4.2, the cloud display is essentially a colored version of the ratio image. This section gives further details on interpretation of a normal display. A change in camera sensitivity, and a number of other problems, can result in an abnormal display. These problems are discussed in Section 10, the trouble shooting section. 5.1 Normal Display Format If everything is normal, one should see a display somewhat like that shown in Figure 3.15. As described in Section 4.2, clouds will be shown in white, with shades of grey in the display corresponding to variations in the ratio. Thin clouds will appear in yellow, clear sky in blue. Offscale dark values will be displayed in black, and offscale bright in solid white. The offscale bright values are included in computing the cloud cover, since they are generally caused by very bright clouds, but offscale dark values are not included. The image is recorded through a fisheye lens. The center of the image is directly overhead, and the edges are near the horizon. North is at the bottom, East on the right, South at the top, and West on the left. This view can be visualized by picturing the view - 49 - you would have of the sky if you were lying on your back, with your feet toward the north. The directions are indicated at the edge of the image with green letters. The occultor position (as read from the sync pulse) is masked with black pixels. The occultor itself is a square frame holding a four log neutral density filter (note that on Line A, one can see the sun point through the occultor on a clear day). 5.2 Track and Color Bars The track is shown on the image, outlined in black. It should be noted that the currently installed version does not give as wide a track as shown in Fig. 3.15, and there are some bugs in the track plotting; most tracks come out Ok, but some are not correct. This will be corrected in the next version of the program. The track is color coded, based on the altitude entered in the track file. A bar chart in the upper right corner gives the color vs altitude code. This color coding does not imply a known cloud altitude; just a known track altitude. A similar bar chart in the lower right corner gives the cloud discrimination color vs ratio value. With a standard calibration correction, a ratio of roughly 130 corresponds to opaque cloud, and 110 is thin cloud. In the example shown, the calibrations were not standard, and thresholds of 80 and 90 were used. The sky cover estimates in the lower left corner are for opaque, i.e., those points exceeding the thick cloud threshold; and total, i.e., those points exceeding either the thick or the thin threshold. 5.3 Selection of Thresholds for Optimal Display Figure 5.1 shows the effect of varying the cloud thresholds. In the upper left, the selected threshold has been optimized. By comparison with the raw data shown in the lower right, one can see that the clear areas have been designated clear (colored blue), and the clouds have been properly identified (colored white). Even those regions of the clouds which are very dark have been correctly identified. - 50 - ዝሕ ኑ በ1 E E ንደ የ 2 % ርክ E SKY COUER ESTIMATE HDHOLE SU NAGER SRY COVER ESTIMATE 2000 2900 1000 580 600 280 108 150 150 125 100 SKY COUER Op 47% Tat 54% SKY COUER Opq - 64% Bika Optimal Thresholds (80, 90) Thresholds Too Low (60, 80) TEMP.24 WHOLE B INAGER SRY COUER ESTIMATE 5008 z WWW 2000 WW W WWW 500 200 180 150 SKY COVER Opq - 8% Tot 23% 75 Thresholds Too High (120, 140) Raw Data for Comparison Figure 5.1 Effect of Varying Thresholds In the upper right corner of Fig.5.1, the threshold is 20 counts too low. Note that in this image, most of the clear regions have been identified as thin cloud. The user could, with experience, recognize this yellow region as a mis-call since it lacks the structure normally inherent in cirrus or other thin clouds. TY The lower left corner of Fig. 5.1 shows the resulting image with the thresholds too high; 120 and 140 in this case. Many of the clouds in this image have been incorrectly identified as sky. Even without reference to the raw image, one can recognize this image as having bad thresholds. The incorrect regions appear in this image as bright blue cloud- shaped anomalies. In general, if there is too much blue, the thin cloud threshold should be lowered. If there is too much white, the thick cloud threshold should be raised. Usually, a separation of 10-30 between the thin and thick thresholds is optimal. It is sometimes easiest to determine optimal thresholds on a clear day. If the thresholds are set too high on a clear day, the horizon and sun aureole will be yellow or white. As the thresholds are lowered, this mis-call at the horizon and aureole should slowly disappear. The threshold at which they first disappear normally gives the most consistent results. This procedure should be done within 3 hours of local apparent noon, since the cloud algorithm sometimes gives over-estimation of cloud amounts near sunrise and sunset. Once the proper thresholds are determined for a system, they generally do not change for long periods. We have made a study of 6-months data we collected with a WSI unit at Columbia, Missouri. This data was found to compare very well with the standard observer over the period. We determined the difference between our standard observation, in tenths, and our simultaneous measurement. For example, if the report indicated 5/10 cover and we measured 60%, we identified this as a 1-category (1/10) difference. We found that our average discrepancy was less than 1/2 of a category (roughly 5% cloud cover difference). This close agreement only occurs, however, when the proper thresholds are selected as described above. - 52 - It should be noted that with the current algorithm, no one threshold will be perfect. The current cloud algorithm will yield results which are slightly biased with respect to angle from the sun. If the threshold is chosen in the above manner, the algorithm may fail to identify the thinnest clouds in the down-sun region. This may be seen in Fig's. 1.1 and 1.2. In general, we feel that this is the best compromise, i.e., missing a few down-sun clouds, but if desired the threshold may be increased slightly to be most accurate in the region near the track. Usually the effect of the directional bias is not severe. Work is progressing on a directionally dependent cloud algorithm. This new algorithm is also addressing problems with the current algorithm near dawn and sunset. Once the optimal thresholds have been selected, they generally will not change, unless there is a hardware fault or gain change. These potential hardware faults are further discussed in Section 9. ... 6. CREATING THE TRACK FILE USING THE MS EDITOR The track file is a data file indicating the expected zenith angle, azimuth angle, and altitude of a target of interest. This may be the track of a drone or satellite, or any other arc of interest to the user. The coordinates should be known in advance, so the track data file can be created prior to running RTIMCLD. 2 . When Program RTIMCLD is run, it will read the track coordinates, convert them to image coordinates, and overlay the track on the cloud image. The altitude of the track is color coded, with blue for high altitude, and red for low altitude. Even though the altitude of the clouds may not be known, the track altitude information was felt to be of use to the meteorologist, who can, to some extent, estimate cloud height from the cloud type (determined from the cloud appearance). 6.1 Format of the Track Data File A sample track data file is shown in Figure 6.1. This file may use any spacing of the columns; i.e., it is read in free format. The values should be integer however, and no more than 100 entries are allowed. (This can be changed in the next version of the program if desired.) · 53 - ODDODDODDODO OOOOOOOO Track Coordinates Amimuth Zenith Altiude (ft) 180 10 180 180 190 200 23000 20000 15000 10000 8000 6000 4000 3000 2000 1000 800 500 300 60. 210 60 60 60 220 230 240 250 60 260 200 510 100 60 80 Figure 6.1 Track data file format The subroutine which reads the track data file expects an initial line with the text "Track Coordinates", followed by three lines which may be blank or contain text as illustrated in Figure 6.1. If the user desires, identifying information may precede the "Track Coordinates" line; the program searches for the first use of this string. The data should start on the fourth line after the "Track Coordinates" entry; i.e., if the text is on line 1, the data starts on line 5. Data should be azimuth angle, then zenith angle, then track altitude. 6.2. Creating an MS File Entry of the data values requires the use of a word editor. We currently use the MS word editor, which in the author's opinion is not very flexible but fairly fast to learn. If the user desires, another editor may be used. There is very little documentation available for this editor, so this section attempts to provide the necessary information. This section, 6.2, describes how to enter a file from scratch, which is the least confusing way to do it. With experience, it is probably easier to edit an existing file, as described in Section 6.3. Creating the File To create a file, one first types "MS" followed by the file name, followed by the "Enter" key. For example, to create file TRACK.DAT, one would type and enter MS TRACK.DAT The user may use any file name acceptable to DOS (1-8 characters with an optional 1-3 character extension after a period). The editor MS will indicate that the file is new, and ask whether you wish to continue, to which the response is "Y" for yes. Once you are in MS, you will find a menu at the top, with the words Block Search Go to Text format Window File There is additional information at the top right, indicating your current line and column, and saying "F10 for pulldown menu". This means that if you wish to use the menu options, - 55 - you hit the F10 key near the lower left corner of the key board. For now, you can ignore the menu, and start typing. Entering and Correcting Text A tab may be used to move you over to the start of a column. The "Enter" key is used at the end of each line of text, or to create a blank line. The key board is used like a typewriter to enter the desired text. If you make an error, and spot it immediately, the easiest way to correct it is with the backspace key; the key with the grey arrow pointing to the left, which is just above the "Enter" key. This will delete the previously typed character. It may be used repeatedly. If the error is back several characters, you may use the four arrows on the keypad to move the cursor to the error. (Be sure the Num Lock light is off, to use arrows; if it is on, press the "Num Lock" key.) The arrows move you in any direction. You may either move the cursor to the incorrect letter and press the "Del" key, to delete the character, or move the cursor to the right of the incorrect entry and use the backspace key. Saving the File Once you have typed in all the information in the format shown in Fig. 12, the file should be saved. This is done by first pressing the "F10" key to obtain access to the menu. The menu options should light up, with the "Block" option highlighted. Enter the letter "F" to access the "File" option. This should bring in a sub-menu, with options such as "Open", "Close", etc. You want the "Quit" option, so press the "Q" key. The editor will ask whether you wish to save your changes, to which you answer "Y" for yes. The file will then be saved, and you will be finished. If you enter the menu by pressing the "F10" key and then change your mind, you may return to the text edit mode by pressing the "Esc" (escape) key. 6.3 Editing an Existing MS File Once you have some experience with the MS editor, it may be easier to edit an existing file than to create a new file each time. If you have one file, say "TRACK.DAT", and wish - 56 - to create a new file, say "DRONE.DAT", you first use the DOS copy command to make a copy of the original file name, in this format COPY oldfilename newfilename That is, for the file names given above, one types COPY TRACK.DAT DRONE.DAT followed by the "Enter" key. Either upper or lower case (or a mixture) may be used. The new file may then be edited by entering MS as before. That is, type MS DRONE.DAT followed by the "Enter" key. At this point, use the arrows on the keypad to go to the entry you wish to change. You may use the "Del" key as described in Section 6.2, first deleting the appropriate character and then inserting the desired character. There is an easier way of substituting the desired characters however. If you look at the top of the MS screen, to the right of the menu choices is a small block that says "IN". This means the Insert key is on, and any entries you make are inserted. If you press the "Ins" key, any entries will be substituted for the current character, rather than inserted. Thus, with insert off, you go to the desired location, and start typing over the old text with the desired new text. You can return to normal insert mode by pressing the "Ins" key again. Once the editing is completed, the file may be saved as before, by pressing the "F10" key, followed by "F" for file, "Q" for quit, and "Y" for yes, save changes. 6.4 Other Useful MS Features There are a number of options in the MS editor, that can be used once more experience is gained. The menu options are listed in Table 6.1. Those which are used frequently are marked with a "*" in this table; those used in handling large files are marked with a "#". - 57 - Table 6.1 MS Editor Menu Options Note: No documentation of these options came with the MS program. This documentation is based on personal experience at MPL. There may be slight differences between these descriptions and the original intent of the program. For example, it may be that those options listed as not operational are in fact operational if the program is installed in some other way. Entries marked with * are used frequently with most files, and those with # are used frequently in handling large files. Block: Brings in menu options for handling blocks of data. # Begin: Defines the beginning of a block at the current cursor location. # End: Defines the end of a block at the current cursor location. # Copy: Copies the currently defined block to the current cursor location. (Keeps a copy at the original location also.) # Move: Moves the currently defined block to the current cursor location. (Deletes the text at the original location.) # Read: Reads an external file into the cursor location. May be used to transfer text from a different source into the file. # Write: Writes the currently defined block to an external file. # Delete: Deletes the currently defined block. Hide/Show: Removes or brings back the normal highlighting which identifies the currently defined block. Spell Check: Apparently not operational. Search: Brings in menu options to allow user to search for text strings. # Find: Finds a no Finds a user-input text string. User will be asked for text string desired, and number of usages to look for. * find/Replace: Finds a user-input text string, and replaces it with a second user- input text string, a user-specified number of times. # Next: Looks for the next occurrence of the previously specified text string. in. Go to: Brings in menu options allowing user to go to specific locations within the file. * Top of file: Go to top of file. * End of file: Go to end of file. Begin block: Go to beginning of currently defined block end block: Go to end of currently defined block # Line: Go to user-specified line number Column: Go to user-specified column number Go marker: Go to the line specified by markers in the Set Marker option. Set marker: The user may mark certain lines, i.e., the fifth line can be set with mark 1, the 14th line with mark 2, etc. This option sets a user-specified marker at the current line. Table 6.1 cont. Text format: Brings in menu options specifying format for display of text. Normal defaults are shown in parentheses. Insert (ON): If ON, any keyboard entry will be insert at the cursor location. Otherwise, a keyboard entry will be substituted for the character at the cursor location. The Menu block will indicate "IN" if Insert of ON. Word wrap (OFF): If OFF, user can input as many columns as desired, within imits, and must press the "Enter" key to start a new line. With the current file, the author was able to write over 2000 characters in one line. If ON, the line ends at the last word which does not pass the right margin, defined below. If ON, the Menu block will indicate "WW". Auto indent (ON): If ON, indents each new line to the start point of the previous line (only if Word Wrap is OFF). For example, this line starts at column 12. If Auto indent is off, using the "Enter" key will return the cursor to column 1; if it is on, the cursor will return to column 12. Left margin (1): Left margin used in Word Wrap ON mode. Right margin (65): Right margin used in Word Wrap ON mode. Tab size (8): Size of tab, when using tab key on keyboard (placed just above "Ctrl" key). Undo limit (20): If one uses a ctrl-Y to delete a line, one can use the "Esc" key to bring it back, or "undo" the delete. Undo limit indicated how many "undo" operations can be done consecutively. Save settings: Apparently not operational. Window: Brings in options controlling use of windows on the screen. If a window is selected, the monitor screen will show two sections of text. One section can be worked with, while the other also shows on the screen. Select: Open: If a window has been opened, select allows one to jump from the upper window, or section of text, to the lower window. Turns on, or opens, the window option. User will be asked how large the window should be. Returns display to the normal single screen, i.e., closes the window. Close: File: Controls opening and closing of the file being edited. Open: Close: 2 Save: save As: Directory: Logged dir: Print: copY: Allows one to open and edit a new file. Closes current file, saving any changes if desired, but leaves user in MS. Asks user for new file to open. Saves current file, with changes. Leaves user in MS, with current file on screen. Saves current file under a new name. Lists contents of current directory Allows user to change directories Prints file currently in MS Copies one file to a new file name. Source file need not currently be in MS Allows user to rename a file. File need not currently be in MS editor. Erase or delete a file. File may not currently be in MS editor. Quit MS. User is asked whether to save changes made to the file. Rename: Erase: * Quit: Yiyyu Once "F10" is hit, to access the menu, menu options may be selected by typing the capitalized letter in the menu. For example, "s" or "S" access "Search", and once in the Search sub-menu, "f" or "F" access "Find", and "r" or "R" access "find/Replace". One can return from a menu without using it by pressing the escape "Esc" key. The menu items may also be accessed after hitting "F10" by using the arrow keys to move the highlight to the desired option, and hitting the "Enter" key. There are also a number of keys which can be used to access various options directly. The table of "Quick commands" is shown in Table 6.2. It is my experience that many of these do not appear to work, however certain ones are very helpful. In this table, the hat sign means to hold the "Ctrl" key. For example, holding the "Ctrl" key down while pressing "A" moves the cursor left one word. The ctrl-Y to delete a line, and ctrl-N to insert a line are particularly useful. In general, for the Track file, the use of a few of the window options mentioned above, combined with the arrow keys, will get the file edited. Some of the other options become useful if a great deal of editing is done, but most are not required for small files. 7. THE CLDSAVE PROGRAM TO SAVE CLOUD IMAGES One of the options on entering Program RTimCld is to loop, i.e., to bring in cloud images from a previous data run and display them in a time loop. If one wishes to use this option, it is best to first save the images of interest. Otherwise the files overwritten, and no longer accessible, the next time the program is run. The batch file CLDSAVE is designed to save the desired files. This section first gives an overview of the file handling in RTimCld, then discusses the details of using the CLDSAVE program. 7.1 Overview When Program RTimCld is running, it automatically writes each cloud image to hard disk. This is in addition to the save to Exabyte which occurs if requested. Files are given the name CLOUDSXX.IMG, where XX begins at 01 and is incremented to a maximum of 99. If the program is grabbing every 5 minutes, it will grab 12 sets an hour, and reach 99 after a little over 8 hours. At this point, the file names start back at 01. Thus a total of 99 files or less are available on disk after a given run. -60- Table 6.2 MS Quick Commands Table 7-1. Micro-Star Quick Command Reference Description Command Description Command G BKSP snorm soás Left word Left character Right character Right word Up line Down line Up page Down page Scroll up Scroll down New line Insert line cócica4- Delete character Delete character left Tab Delete word Delete line Reformat paragraph Toggle insert mode Replace last find/replace Abort current command Insert control character Beg/end of line "Z RETURN *N . ESCAPE F10 O‘A OºB "OʻC "OʻD QE QºF '01 "OʻJ "OʻR "OʻK O`S O‘Y Q 1..9 Find and replace "OʻC Cursor to beginning of block "OʻG Cursor to end of file 01 Cursor to end of line "OʻK Find "OʻL Toggle autoindent mode O'N Jump to marker (prompt for #1 'Oºo Cursor to beginning of file "OʻR Cursor to end of block "OʻS Cursor to beginning of line "O'w Delete to end of line "OʻY Jump to marker (fast) Center line Go to other window Go to column Change case Left margin Go to line Open second window Right margin Set undo limit Toggle word wrap Close window KºB KºC "K^D "KH KK K‘M 'KR K^S Begin block Copy block Open file Hide/display block (toggle) End block Set marker (prompt for #) Read block Sae file KT "K^O "K^V K^W Kºx KY KºX *K 1..9 Set tab spacing Abandon file Move block Write block Write block Exit program Delete block Set marker (fast) From: Turbo Editor Toolbox, version 1.0, Owner's Handbook, (1985) Borland International, Inc., Scotts Valley, CA, p 45. Note: Whereas many of these commands work with the editor as currently installed, many others do not appear to work. As an aside, it should be noted that in the looping which may occur within the 5- minute wait period, the program is smart enough to recognize whether or not the file names have reset to 01, and display the period asked for, whether the file names are contiguous or not. If the program is stopped, and started at a later time or on another day, the files written to disk will once again start with the name CLOUDS01.IMG. This means that files written on the previous run are written over. This was done intentionally; if the program used a different set of file names each day, the disk would soon fill unless the user took the time to clean it out. By writing over the old files, the disk does not get over-filled automatically. the user wishes to access the files on a later date, a deliberate step must be made to save the files. The CLDSAVE batch program is designed specifically to save the desired files. Program RTimCld also alerts the user to use CLDSAVE if desired. 7.2 Required Disk Space Before using the CLDSAVE program, the user should determine whether there is sufficient space on the disk for saving more files. The next version of CLDSAVE will do this automatically. At present these steps are left to the user. Space Required by the Program The disk should always have enough space for the 99 files required for normal running. Each image requires .24576 megabytes (Mb), so 99 files require 24.33024 Mb. Thus one should plan to leave about 25 Mb available. However, if one already has several CLOUDSXX.IMG files on disk, the space these use can be included, since they will be written over. That is, if one has 10 Mb used in these files, one only needs an additional 15 Mb free. To determine how much disk space is currently used by these files, type DIR CLOUDS* IMG followed by the "Enter" key. This will list all the files in the directory beginning with "CLOUDS" and ending with ".IMG". Multiply the number of such files by .25 Mb (the -62 - approximate space required for one file), subtract from 25 Mb, and this will tell you how much free space you need. For example, if you have 60 cloud files, then you need to leave free 25 - 60 ( .25) = 10 Mb. Space Available on Disk You may note that at the bottom of the directory listing created by the above command, the total space available on your disk is listed. This will be in a format such as follows: 38 File(s) 25063424 bytes free In this sample, the disk has 25 Mb free; if 10 Mb is required, there are 15 Mb available which are not needed by the RTimCid program. If you do not have any spare space, then it is time to clean house. Section 8 describes various utilities for accomplishing this. If you wish to save some of the files from a given run, for later demonstration, first you need to figure out how much space they will require. With about 15 Mb to spare, one can save about 60 files (although it might be wise to save only those you really want). Having figured out how many you can save, you next use the CLDSAVE program to save them, as described in the next section. 7.3 Running the CLDSAVE Program The CLDSAVE program will save all the CLOUDS images, so if you do not wish to save all of them, you should first delete those you do not wish saved. See Section 8.2 for instructions on deleting files. (This is something that will be automated in the next version of CLDSAVE.) For example, if you have files CLOUDS01.IMG through CLOUDS23.IMG, and wish to save only CLOUDS13.IMG - CLOUDS23.IMG, you should delete CLOUDS01.IMG - CLOUDS 12.IMG, as described in Section 8.2. Next, choose a 6-character name to replace CLOUDS. For example, it the data is from 6 June 90, you might choose 06JU90. Next type CLDSAVE Fname - 63 - followed by the "Enter" key, where Fname is the 6-character file name you have chosen. If this name is 06JU90, the files CLOUDSXX.IMG will be renamed 06JU90XX.IMG. If the user does not enter a file name, the program will tell the user to try again, using a 6- character file name. If you wish to view these images, then when starting RTimCid, request the loop option. In response to the queries give it the file name 06JU90, then the starting and ending number, i.e., 13 and 23, in the above example. Fig 3.10 shows the screen format for this portion of the RTimCld program. 8. OTHER USEFUL COMPUTER FUNCTIONS There are a number of computer functions available to the user through DOS, as well as some utility programs from MPL. This section describes the use of two of the DOS functions, and two MPL utility programs. For further information on DOS, consult any of several user guides on DOS for the PC. The real time system currently uses Microsoft MS- DOS. 8.1 Changing Directories Usually the user of RTIMCLD will not need to change directories in normal operation. If desired however, one may change directories by using the "cd" ("change directory") command. For example, to go to a directory named "save", which is a subdirectory of a directory named "calib", one would type cd \calib\save In all of the examples in this section, the entry is followed by the use of the "Enter" key. The backslash separates directories from other directories. The root directory is symbolized by a 'M". Thus if one is in some directory, and wishes to go to the root directory, type cd \ - 64 - If one wishes to go to the "Calib" directory, then one types cd \calib The real time program is kept currently in directory rtimcld, so the user may return to the normal directory by entering cd \timcld 8.2 Deleting Files Files may be deleted through the use of the "del" ("delete") command. For example, if one wishes to delete files CLOUDS01.IMG - CLOUDS12.IMG, but leave files CLOUDS13.IMG - CLOUDS 23.IMG intact, one would enter del clouds01.img and then repeat for images 02 through 09. An easy way to repeat the command is to hit the "F3" key. This will bring back the previous command, which may then be edited. That is, after entering the above delete command, hit "F3", and the computer will show the same delete command on the screen, with the system waiting for the use of the "Enter" key. Before using the "Enter" key, however, first use the left arrow on the key pad to backspace to the "1", and type "2.img". At this point, you should see del clouds02.img and can press the "Enter" key. The * wildcard The * wildcard is very useful in using the delete command. Suppose one has used CLDSAVE to create a set of files TEST0113.IMG through TEST0123.IMG, and now wishes to delete these files. This may be done conveniently by entering del test01*.img - 65 - The * is interpreted to mean any combination of characters; thus all 9 of the above files will be deleted. In using wildcards, beware of deleting too much. It is generally best to use the directory command first, to see how much will be deleted. By entering dir test01*.img you will get a listing of all files which have test01 at the beginning and .img at the end, and can verify that you wish to delete all of these files. This helps protect you from forgetting that there may be other files such as TESTO124.IMG through TEST0199.IMG that you do not wish to delete. Be especially careful not to use "del *.*", as this will erase everything within the subdirectory. This command may be used under special circumstances, after one has read a regular DOS manual and is familiar with the operating system. But it is important to use the "dir" command first, to be sure everything really should be deleted. The new user is generally advised to avoid this global delete. Using this command while in the RTimCld subdirectory would result in erasing the program and any files that have been saved. 8.3 Program EXBACK for Saving Files The exabyte tapes may be used not just for saving images, but as a storage medium for saving any combination of text files and images. Program EXBACK, written at MPL, performs this function; it backs up data from disk onto exabyte tape. ! Appendix 1 contains Memo AV90-024t, which gives the details for using this program. For most purposes, it is sufficient to be familiar with only a few options, listed below. In general, one types the command "exback", followed by any desired options, followed by the file name. The most common options are --, -a, and -d, as described below. The file names may use the "*" wild card just as the "del" command does. The "r" Option The -r option means to rewind the tape first. For example, the command ea - 66 - exback -- *.img will rewind the tape, and save any files in the current directory which end with ".img", thus saving all the cloud image files. The command exback -- ** will save all the files in the current directory. The "a" Option The -a option is used to append to tape. Thus, if you saved all the image files previously, but have more now that you wish to add to the previous tape, type exback -a ** The program will search for the end of the data on tape, and append to it. Seessa WA The "d" Option The other commonly used option is exback -rd ** As before, the "r" instructs the program to rewind the tape. The "d" instructs the program to go to the root directory and start backing up files in all directories. Since the ** was used in this example, this command will back up all files in all directories. This is done for general system backup, to protect against hard disk failure. (It does not prevent hard disk failure, however it will allow one to recover the files saved on tape if the hard disk does fail.) One can also simply enter exback - 67 - in which case the program will display all the options in a menu. For more details see Appendix 1. 8.4 Program EXRCVR for Recovering Files MPL's program EXRCVR recovers files; that is, it transfers them from exabyte to hard disk. It is best to write protect the tape first. That way if you get confused and use EXBACK, you won't write over the contents of the tape. Using EXRCVR will normally write over whatever you have on hard disk, if it has the same file name. Listing Tape Contents If one wishes to list the contents of the tape to the screen, without copying to hard disk, one enters exrcvr -rd ** which will list the contents of the tape. In this command, "r" means to rewind, as it did in EXBACK, but now the "d" means to list a directory to screen rather than recover files. The command exrcvr -rd *.img will list any files on tape which end with ".img". If one wishes to divert this output to a file, rather than showing it on the screen, one enters exrcvr -rdw ** In this case, the contents of the tape will be listed in the file dir.lst (directory listing). Recovering the Files Once the user decides to go ahead and recover the contents of the tape, the command to use is exrcvr -r * * - 68 - The command exrcvr -r test01*.img will recover those files which start with "test01" and end with ".img". In recovering files, the user should be aware that this procedure will overwrite any previously existing files of the same name on the hard disk. If desired, the user may use the -t option, in which case the files will be recovered only if they are more recent than those already on disk. For example, the command exrcvr -rt ** will rewind the tape and recover all files from tape that are not on disk currently and any that have a more recent creation date than the files of the same name on the disk. As with EXBACK, one may simply enter "exrcvr" to see the available options. One should also be careful to use the right program. If one enters EXBACK, when EXRCVR is desired, the tape will be overwritten unless write protected. On the other hand, if one enters EXRCVR when EXBACK is desired, the files on disk will be overwritten. We plan to add a cautionary note to the user to be certain that the user understands which program should be used. 9. TROUBLE SHOOTING This section attempts to describe the various failures which can occur due primarily to hardware faults. Many of the faults described below may never happen at a given site; they are based on a two or more year experience with roughly 10 camera units and 20 computer units. Many of the problems which may occur will require help from MPL, however some may be fixed on-site. 9.1 Computer Start-up Failure On start-up, the computer should normally go through a series of operations which result in text similar to that shown in Fig. 9.1 appearing on the "CMPTR" data line. There 96 -69. 000OVOG 0 The TMI INDUSTRIAL COMPUTER BIOS B286 Version 3.0 Copyright (c) 1985, 1986. Phoenix Technologies Ltd. All Rights Reserved .0R1 DOUDOUBOOOOOOOON....... 6.600ROWO... OOOOOOOOOOO DOOOOOOOOOOOOOOO .GOOOOOOO O OOOOOOOOOOOOO OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO 640K Base Memory, 00384K Extended Advanced Storage Concepts SCSIBIOS - ver. 3.3 date - 12-Aug-87 OOOOOOOOOOOOOOOOOOOOOO 六六六六六六六六六六六六六六六升升升升升升升升升升升升升升升升升升升升升升升升 ​* * * SE A G A TE DISK MANAGER (tm), VERSION 3.50 SERIAL NUMBER S03729291 * COPYRIGHT (C) ONTRACK COMPUTER SYSTEMS, 1985 - 1988 * * 术术¥¥¥¥¥来来来来来来来来¥¥¥¥¥¥¥¥来来来来来来来来来来来来来来来来来¥¥¥¥¥¥孝孝养羊 ​3.5 INCH EXTERNAL DISKETTE BIOS DRIVER INSTALLED. Version 1.0 (C) Copyright IBM Corp. 1985 MSMOUSE V4.56 - Mouse installed on COMI: Loaded External Disk Driver for Drive E C>Echo Off D: D:\RTIMCLD Fig. 9.1 Screen Output on "CMPTR" Line During Computer Start-up may be slight variations in the text depending on the exact contents of the start-up files. There are a variety of problems which can cause this start-up to halt. 9.1.1 System Hangs with No Message On occasion there is a random failure that appears to have to do with access to RAM, but is not associated with any component failure. On these occasions, the system gets as far as the fourth line, listing the size of base memory and extended memory, and just hangs. No error message is printed; it simply fails to proceed. When this happens, it is best to turn off the computer, let it sit a moment to let the hard disk spin down, and turn it back on. Usually this will fix the problem. 9.1.2 Hard Disk and/or Controller Failure If the hard disk fails, you may receive a message after line 4, indicating "Hard disk controller failure. Hit F1 to continue." In this case, hitting F1 usually gives the message "No boot device available", meaning that it has found no alternate disk with the DOS system on it. Try turning the system off, letting it sit a moment, and turning it back on. Sometimes when the hard disk is starting to fail, this will work after several tries. If you are successful, then the program will often run; however MPL should be alerted that the disk may be going bad. If this does not work, alert MPL, as the hard disk will probably need to be replaced. 9.1.3 CPU Failure There are a number of messages one can get due to CPU failure, as documented in the TMI manual. One such message is "Parity error". Normally, this will require attention from MPL, however it is sometimes possible to recover by turning the system off, letting it sit a moment, and turning it back on. Normally these problems require changing the CPU card, but sometimes similar symptoms may occur if the setup file is distorted. In either case, it is best to alert MPL. . 71. 9.2 Missing or Abnormal Imagery on Line A Data line A normally shows the live video signal coming in from the camera. There are several types of failure which can affect this image. 9.2.1 No Image Present If there is no image, first check if the Master system is turned on. The camera receives its power from the master computer, and will not have an output if the computer is off. Similarly, there may be no signal if the MPL repair team is working on the system, which may be disconnected. If the master computer shows a signal on Line A, then the problem is somewhere between the master and slave. The video connection is illustrated in Fig. 9.2. As shown in this illustration, there are several components between the master and slave; including the video digital amplifier, the transmitter, the fiber itself, and the receiver. Any of these components could fail, or be disconnected. Trouble shooting the fiber components can be done by site personnel familiar with the fiber hardware. However, any changes in any of these components can alter the calibration of the system, so it is important to alert MPL personnel. 9.2.2 Images Appear Dark The WSI master system is designed to run from 6 hours before local apparent noon (LAN) to 6 hours after LAN. The system is designed to open the aperture as required, however in the winter there will still normally be a period of time at the beginning and end of data taking when the sky is dark. Under these conditions, the system will continue to acquire images, however the data will be rejected during the image processing. web If the sky is not dark, but the images are dark, the most likely cause is a problem with the fiber linkages or the fiber receiver gain on the video line (see Fig. 9.2). There is a small gain adjustment on the video receiver. This should not normally be adjusted, as it changes the calibration of the slave signal. If the fiber itself has had no changes, it is best to alert MPL. Incidentally, there are also gain adjustments on the distribution amplifier, but these should not be touched, as they affect the calibration and at present can only be readjusted properly if returned to MPL. - 72 - MASTER: CAMERA ACCESSORY CONTROL PANEL A IN MONITOR UNTERMINATED A OUT SLAVE: 7 FIBER IN 1 OUT 1 - XMIT REC'V VIDEO DISTRIBUTION AMPLIFIER MONITOR A IN UNTERMINATED A OUT IN 2 FG100 IMAGE BOARD (TERMINATED) FG100 IMAGE BOARD (TERMINATED) Α MONITOR TERMINATIONS (BOTH MONITORS) A OFF OFF SYNC ON RON G ON ON B ON Figure 9.2. Video Installation Configuration 9.2.3 Images Appear Noisy As the cameras get old, there is more system noise. This will generally appear as variations in brightness in the dark part of the image, or more generically, as "speckly" images on Line A. MPL monitors the state of the cameras continuously, as the master tapes are returned to MPL for processing, and cameras exhibiting "speckly" outputs are changed as soon as possible, given schedule and funding limitations. 9.3 Missing or Abnormal Imagery on RGB Line The image in the RGB line depends on the behavior of the FG100 imaging board. There are a number of symptoms that can indicate faults; some of these are recoverable, and some are not. 9.3.1 No RGB Image If there is no image at all, then there is a chance that the FG100 cable has become unplugged. On the back of the computer, there is a small grey ribbon cable which comes out of the back of the small terminal box with 6 BNC connectors. (Normally only 5 of these BNC connectors are used.) The ribbon cable should be inserted into the back of the board which has a small black rectangle around the connector. When correctly inserted, the red edge of the ribbon cable is up. If this cable is loose or out, it should be reinserted, being careful not to bend the pins on the board. Given that the MPL staff normally ensure that the board is properly seated and connected prior to leaving the site, the most likely cause of no image is a failed FG100 board. If the FG100 cable is properly inserted, try turning the computer off and back on. If the image on RGB is still black, then the board is probably bad. In this case, it is necessary to contact MPL. If the RGB screen is black except for a red or white message indicating "AWAITING SYNC", this is a different problem which is addressed in Section 9.4. - 74 - 9.3.2 "Pepper" on Image On rare occasions, we have had an intermittent fault with the FG100 board look up tables (LUT's). In this case, the grabbed image can appear to have black pepper on it, in the approximate form of an iso-radiance curve. Or, the color image may be speckled with a variety of colors. Samples of these abnormalities are shown in Fig. 9.3. The upper half shows a normal input image on the left and the effects of a bad input LUT on the right. The bottom half shows a normal output image on the left, and the effects of a bad output LUT on the right. When the LUT is bad, restarting the program will reinitialize the board, resetting the LUT's, and may temporarily fix the problem. Once the board initializes properly, it should remain correct for the duration of the run. It will reinitialize next time the program is started. Once the LUT problem starts occurring intermittently it tends to get worse with time, i.e., starts occurring more frequently, so MPL should be alerted. This is not to be confused with the system noise described in Section 9.2, which appears on the A line as well as RGB. If the problem is in look up tables, the problem will appear only on RGB. 9.3.3 Other RGB Abnormalities If the FG100 board begins to fail, there can be a variety of symptoms. Images can appear to be off-center; letter size on the image labels can appear abnormal; images can appear at half normal size. None of these conditions appear frequently, however in two years of operating roughly 20 boards, these symptoms have been seen at one time or another. In general, if the image appears abnormal, it is best to make a run with the exabyte option enabled, and send the sample tape to MPL for evaluation. Fig. 9.4 shows an abnormality caused by operator fatigue. When the screen starts to look like this, it is time to go home - you've been looking at too many images. - 75 - ។ UT VIO ពួក Normal Input Image Effect of Abnormal Input Look Up Table BITCOVEK ESTIMATE BRY COUEN ESTANTE 2800 EBEBA 1 1000 1800 500 680 200 200 100 150 150 125 125 ORA IAIA OB EIGINA 100 100 SKY COVER Opqm 47% Tot 54% SKT COVER Opa - 47% Tot 64% 75 75 Normal Output Image Effect of Abnormal Output Look Up Table Figure 9.3 "Pepper" on the RGB Image Figure 9.4 Sample RGB Abnormality 9.4 Image on RGB stays Black, with "Awaiting Sync" Message As described in Section 4.3, the real time system is dependent on a timing signal from the master computer. If this signal is not clean, the system can hang while waiting for sync. In this case, the RGB image will be black, with the message "Awaiting Sync" appearing in red in the lower left corner. There are several possible causes of this. If it is more than 6 hours from local apparent noon, the master program will be waiting for the next day. Under these conditions, there will be no sync signal, but there will be a video signal, since the camera power is still on. In the summer, it can be daylight during this period. In this case, the user must wait until the normal LAN-6 hr start time. If it is within 6 hours of LAN, and the CMPTR line has no errors noted (see Section 9.5), the problem is probably in the sync signal. It is possible to see what is coming in over the filter in RS232 format, by pressing the "R" hot key (ref Section 3.5.5). When this is done, any RS232 information received by the computer over fiber will be printed to the screen on the CMPTR line. If the message is incomplete or garbled, the fiber or transponder pair may be faulty. If no RS232 signal is being received over fiber, and the fiber and transponders are still connected, the problem may be the gain at the slave transponder end. The setting of this gain is fairly critical; if not quite right, no sync signal is received by the computer. The proper setting of this gain is determined empirically by adjusting it slowly till a signal is received. The signal is only transmitted at the beginning of each minute (of master computer time), so it is necessary to make a small adjustment, wait for the next signal, and then make additional adjustments at one minute intervals as necessary. 9.5 System Appears to Hang During a Program Run When the system appears to hang in the middle of a Program RTIMCLD run, the most frequent cause is an inadvertent keyboard entry. If someone brushes by the system, and hits a key, the program will treat it as a hot key. If the key is not one of those described in section 3.5, the system will stop and query the user regarding the user's intentions, in the following format: - 78 - Please type C to change color flag, D to change Save RaDiance flag, T to change Save Ratio flag, S to change Smooth flag, R to show RS232 diagnostics, X to exit program, or press ENTER to change nothing. When this message appears, the computer will hang until a response is made. In this case, press the "Enter" key, and the program should continue. In the next version of the program, we intend to add a timer, and have the program continue if no response is made within a short interval. 9.6 Occultor Looks Abnormal The occultor can appear abnormal in several different ways, and for a variety of causes. 9.6.1 Occultor is not aligned with the sun on Line A If the occultor is not aligned with the sun, i.e., the sun is not in the center of the occultor as seen on Line A, there may be one of a variety of problems. First, it the sun is too far north or south with respect to the occultor, then the wrong occultor arm may be on the camera. Check the WSI Operations Manual at the master site, for the occultor arm schedule, to determine if the right arm is in place. (The arms are marked with white bands to indicate arm number.) If the occultor is not aligned along an east-west line, then the arm may be misaligned or the clock at the master end may be off. At the master end, there is a clock radio which accesses WWV time, however this clock may be inoperable, or not receiving a proper signal, or the serial port may not be handling the clock output properly. By looking at RGB at the master end, one can see the time written on the image. If it ends with a W, the computer is accessing WWV, and the time should be correct. If the time ends with a B, the system is using BIOS time. In this case, note whether the time appears to be correct. If BIOS is being used, and the time has drifted, it can be reset with guidance, over phone, of . 79. MPL personnel. Since the occultor position is driven as a function of clock time, an error in the time will result in an error in occultor position of 1 degree for each 4 minutes of clock error. If the occultor is not aligned along an east-west line, and the master system clock time is close, then the occultor is probably misaligned. Instructions for aligning the occultor are in the WSI Operations Manual. Essentially, the ACP is manually set to 90 degrees, the set screws on the arm are loosened, and the arm is lined up vertically. Once the clock is correct, and the proper arm is aligned, the sun should be reasonably well centered in the occultor. 9.6.2 Occultor Mask is not lined up with Occultor If the occultor is badly misaligned, the occultor mask which is input on the RGB image during image processing can fail to completely cover the occultor in the image. For example, if the occultor is actually at 100 degrees when the occultor readout indicates 90 degrees, the mask will cover where the occultor should have been. Similarly, if the wrong arm is used, the mask will cover the normal location of the correct arm. In this case, the occultor should be changed and/or aligned as discussed above. The occultor mask can also be misaligned with the actual image of the occultor due to a fault in the occultor readout. On some systems, there are occasional spurious readout values of the occultor value. If the occultor position is read out as a number less than 0, greater than 180, or more than 5 from the expected position, as computed from the time, then the mask will be placed at the expected position. In this case, the expected position may or may not match the actual physical position. Normally these spurious readouts are quite rare, however if they occur frequently, this may indicate a requirement for a new occultor drive. In addition, if the slave clock drifts more than 20 minutes with respect to the master clock, the computed occultor position will differ from the actual position by more than five degrees, and the mask will not be aligned. Fig. 9.5 shows a sample of this occultor abnormality. The top half shows a normal image; the bottom half shows a misalignment of 10 degrees. In this case, the slave system clock can be updated with the help of MPL personnel. . 80- 5888 S3 CODEK ESTIMATE 2000 1000 BRE 500 200 150 ت ستم لا 125 س T ا ع = = SKY COUER Opq = 47% Tot = 54% = 75 Normal Image SBT COVEK ESTIMATE 2000 1000 500 200 100 150 125 SKY COVER Opa = 47% Tot = 54% 175 Mask is off 10 degrees Figure 9.5 Sample Occultor Misalignment 9.7 Cloud Indication is consistently clear or overcast If the cloud indication is consistently too high (too much cloud) or too low (too little cloud), the most likely problem is that the cloud threshold needs to be changed. Section 5.3 discusses methods for evaluating the threshold. Currently, the system is consistently indicating too much cloud. On the two installation visits by MPL, the site personnel were unable to provide a video fiber link until a couple hours before departure. As a consequence, the system field calibration was not completed. One can compensate for this temporary calibration abnormality by using lower thresholds. In addition, a number of hardware elements mentioned earlier can change the calibration constants, and may cause the resulting cloud images to be abnormal. If the gain is changed at the distribution amplifier, on the video receiver, or in the fiber connections, we could see changes. Currently, the cross calibration of the master and slave is a function performed by MPL. Sometimes the camera sensitivity or A/D on the FG100 board change abruptly. In this case, the offending component would need to be replaced. If in doubt, it is best to run the program with the exabyte write enabled, and send a tape to MPL for evaluation. 10. RECOMMENDED SYSTEM REFINEMENTS There are a number of system refinements, both in software and hardware, which are currently proceeding. In addition, there are more long term goals, which are in various stages of planning. These are discussed below. 10.1 Short Term Refinements 10.1.1 Cloud Cover along the Track As discussed in Section 3.3.2, the geometric coordinates of a track or region of interest may be input to the program, and plotted on the cloud image. It is our intent to compute cloud cover within some "sidewalk" region representative of the track. This also entails a change in the track plotting logic, as the track is currently plotted using a - 82 - purchased software library which does not lend itself to the more complex problem of computing the cover within the track boundaries. There has also been some discussion of allowing the user to indicate time of an expected satellite passage along the track. 10.1.2 User Interface We are currently testing options for improved text display on the CMPTR line. Once the program is into the grabbing and image processing, it would be nice to have part of the CMPTR line screen show the current state of the program, while part of the screen shows the cloud cover history. Over a slightly longer term, we would also like to look into the possibility of using windows, so that a mouse could be used rather than a keyboard when possible. This could be particularly useful in the start-up portion of the program. 10.1.3 General Cleanup There are a number of features already mentioned in the text, which need cleanup. Perhaps one of the most important features is a timing loop added to the hot key options, so the program does not hang when the keyboard is inadvertently touched. There are a number of other such corrections in the immediate plans. 10.2 Longer Term Refinements 10.2.1 Prediction There is interest in having the program make short term predictions of the cloud cover over the track. Currently, we feel this could probably be achieved through detection of the motion of the cloud edges near the track. This edge motion would be the compound effect of both cloud development, and cloud translation. This scheme may involve going to a finer time scale, and perhaps working more directly with the radiance images for the motion detection. 10.2.2 Cloud Discrimination Algorithms As a part of other projects, we are working on an improved cloud discrimination algorithm, which would handle the directional dependence in the red/blue ratio better, and adjust for the changes near sunrise and sunset. If and when this development is completed, - 83 - it would probably be feasible to introduce this enhancement into the current real time program. 10.2.3 Cloud Base Detection Depending again on other projects, we may be driving toward determining cloud base height. Our current thinking is to implement this through a relatively low power, hand held lidar, mounted to the WSI unit and servoed by the real time system. When this development occurs, this will be a significant enhancement to the real time system. 11. SUMMARY The real time cloud system has been installed, and is able to generate determinations of cloud cover in near-real time, at five minute intervals. The system receives a timing pulse from the WSI unit, and records images in four spectral filters. From these, an image of the cloud cover is derived, and displayed for the user. A track of a satellite or drone may be input if desired, and displayed on the image, in order to allow visual evaluation of the image in the region near the track. Percent cloud cover is derived for each image. Time series of images may be displayed, either during the program, or later, if desired. Although this system is installed and working, we are developing a number of new enhancements. Some of these, such as potential changes in the computer output display, have to do with ease of use of the system. Others such as addition of the cloud cover along the track, represent enhancements to the actual capabilities of the system. 12. CAUTIONARY NOTE The algorithms, processing techniques, and source code are proprietary in nature. They were developed over several years, under several differently sponsored contracts. Distribution of the source code is therefore limited. Although an overview of the algorithms is provided here, understanding of the full impact of the various logical components requires a detailed knowledge of the WSI system performance at both the radiometric and video levels. - 84 - 13. ACKNOWLEDGEMENTS Substantial contributions to the WSI development, analysis, and quality control, have been made by the following members of the Optical Systems Group: Melissa Ciandro, Wayne Hering, Monette Karr, Tom Koehler, John Malo, Peter Pak, Harry Sprink and Jack Varah. The authors wish to thank these individual for their continued enthusiastic dedication. We also wish to thank the following individuals for their valuable support in publication: Monette Karr, Phil Rapp and Carole Robb. - 85 - Appendix A Optical Systems Group Marine Physical Laboratory Scripps Institution of Oceanography University of California, San Diego John A. Malo, Jr. Instructions for EXBACK and EXRCVR EXBACK Version 5.4 EXBACK is an EXabyte BACKup utility. It is designed to copy files from disk to be stored digitally on 8mm video cassette tapes via SCSI interface to EXABYTE. There are two ways that the program can be run. One is by menu and the other is by cominand line. EXBACK will not back up files that are hidden. Hidden files are files that do not appear in directory listings. These files include system files, such as 10.SYS, which are used by DOS. . WARNING: If EXBACK is not used in append mode it will overwrite any exiting information written to tape. As a result, when the program is initially started the user will be prompted to press the ESCAPE key to continue. If any other key is pressed the program will abort. EXBACK Using the Menu To use EXBACK, type "EXBACK" at the prompt. A menu will be displayed. EXBACK will assume the user wants a menu when no parameters are specified. Parameters are explained in the command line section. 1 The "a" option is used to append to tape. This is the default. If the rewind option "r" (This option will be explained later) is not used, the "a" option does not need to be specified. EXBACK will automatically append to the tape. When EXBACK is in append mode the end of the data on the tape is searched for before the information is written to tape. The "b" option is used to mark a file as having been backed up or archived. When used the Disk Operating System (DOS) ſile archive bit is flipped to mark the file as having been backed up. The "C" option, when used, checks the file to see if it has been changed since its last backup. This allows the user to back up only new files and files that have been changed. This option will not mark the file as having been archived. The "d" option is the backup option. When chosen, EXBACK does a search through all directories looking for the files specified. When using this option, do not specify the drive nor the path or EXBACK may not backup the files you intended to back up. Start EXBACK on the drive that you want to back up. NOTE about the archive mark: The archive is marked by flipping the DOS archive bit of the file. This is the same archive bit that is used by the DOS backup utility. Thus if the "c" option is used to back up files after a DOS backup, those files backed up by DOS will not be backed up by EXBACK. Similar, if the "b" option is used to back up files, these files will not be backed up by the DOS backup utility. It is suggested, if the user is going to back up a disk onto both tape Appendix A and disk, to do the tape backup first and use the "C" option and not the "b" option. This will leave the archive bit unchanged for the DOS backup utility. See a DOS manual for more information on the DOS backup utility. The "e" option allows the user to specify files for backup. Files may be backed up by giving the exact file name or by giving a file pattern. When the "e" option is chosen, the user will then be prompted for a file name or pattern. At this point the user may enter one file name or pattern. The "e" option must be chosen once for every file name or pattern. A file pattern is a file name that contains a "wildcard". The wildcards are the "*" and the "?". An "*" will match zero or more characters and the "?" will match exactly one. Examples of file patterns: *.img Will match any file name ending in ".img". Will match any file name starting with "pic". pic* * NOTE: Characters to the left of an "*" and before a "." must be exact. Any character to the right of an "*" and up to the dot will be matched. If there is an "*" after the "." it will work the same up to the end of the name. pic*m.*kj Will match the same thing as pic*.*. The "on", "k", or "j" will not effect the pattern. p?c.ext This example can only have the second character different. (NOTE: pc.ext is not a match, but if the pattern is changed to p*c.ext pc.ext is a match.) ???.?? This example will match any file name that has three letters before the dot and two letters after. Drive names and paths may be specified with the filename. There may not be any wildcards used for the drive or path, but the filename may still contain wildcards. A drive letter need not be specified with the path or the path need not be specified with the drive. Example drive and path specifications: D:pic.img Will match the file "pic.img" in the D drives's current directory. D:\pic.img Will look in the root directory of the D drive for the file "pic.img". Will look in the root directory of the current drive for the file "pic.img". \ic.img Vimage\pic.img If a directory named "image" exists in the root directory of. the current drive, this directory will be searched for the file "pic.img". D:\image\pic.img If a directory named "image" exists in the root directory of. the D drive, this directory will be searched for the file "pic.img". Appendix A The "q" option will quit the program. The "r" option rewinds the tape. If the "r" option is specified and the "a" option is not, EXBACK will start writing at the beginning of tape. If there is any previously existing data, it will be overwritten and destroyed. C The "u" option resets all the options to the default. It will not remove the file names and patterns entered by using the "e" option. To remove filenames and patterns the user must quit EXBACK and start over. After the user selects the parameters, the user must press the ESCAPE key before EXBACK will begin processing. EXBACK Using the Command Line. To use EXBACK in command line form, the user must type EXBACK at the DOS prompt followed by a list of parameters: C:\> EXBACK (-options] [file names... ) [file patterns ...] The parameters are the options, file names and file patterns. If an incorrect option is chosen a listing of the usage will be displayed. If no parameters are specified EXBACK will assume the user wants to run the program in menu form. The order of the parameters will not affect the way EXBACK saves files. Options are preceded by a "." or a "/". Both symbols have the same meaning. The user may specify one or more options after a single option symbol or specify each option in the line with its own option symbol The "a" option is used to append to tape. This is the default. If the rewind option "r" is not used, the "a" option does not need to be specified. EXBACK will automatically append to the tape. When EXBACK is in append mode the end of the data on the tape is searched for before the information is written to tape. The "b" option is used to mark a file as having been backed up or archived. When used the Disk Operating System (DOS) file archive bit is flipped to mark the file as having been backed up. The "c" option, when used, checks the file to see if it has been changed since its last backup. This allows the user to back up only new files and files that have been changed. This option will not mark the file as having been archived. NOTE about the archive mark: The archive is marked by flipping the DOS archive bit of the file. This is the same archive bit that is used by the DOS backup utility. Thus if the "c" option is used to back up files after a DOS backup, those files backed up by DOS will not be backed up by EXBACK. Similar, if the "b" option is used to back up files, these files will not be backed up by the DOS backup utility. It is suggested, if the user is going to back up a disk onto both tape and disk, to do the tape backup first and use the "c" option and not the "b" option. This will leave the archive bit unchanged for the DOS backup utility. See a DOS manual for more information on the DOS backup utility. The "d" option is the backup option. When chosen, EXBACK does a search through all directories looking for the files specified. When using this option, do not specify the drive Appendix A nor the path or EXBACK may not backup the files you intended to back up. Start EXBACK on the drive that you want to back up. The "e" option writes end of file marks every 25 files. If it is not specified, a file marker is only written after the files have been saved to tape. This option can only be specified in the command line. It is not an option if the program is being used in the menu form. The "r" option rewinds the tape. If the "r" option is specified and the "a" option is not, EXBACK will start writing at the beginning of tape. If there is any previously existing data, it will be overwritten and destroyed. If no file name(s) and/or pattern(s) are specified no files will be saved to tape. Drive names and paths may be specified with the filename. There may not be any wildcards used for the drive or path, but the filename may still contain wildcards. A drive letter need not be specified with the path or the path need not be specified with the drive. EXRCYR Version 5.4 EXRCVR is an EXabyte ReCoVeR utility. It is used to recover files, and display the file names of files saved by EXBACK on 8mm video cassette tapes. EXRCYR Using the Menu. To use EXRCVR, type "EXRCVR" at the prompt. EXRCVR will assume the user wants a menu when no parameters are specified. The "d" option is used to display the names of the files on the tape. It displays all file names from the current position of the tape unless the rewind option is also used. If the rewind option is also used then the names of all files on the tape are displayed. When the display option is used no files will be written to disk. The "e" option allows the user to specify the files for recovery. Files may be recovered by giving the exact file name or by giving a file pattern of files on the tape. When the "e" option is chosen, the user will then be prompted for a file name or pattern. At this point the user may enter one file name or pattern. The "e" option must be chosen once for every file name or pattern. A file pattern is a file name that contains a "wildcard". The wildcards are the "*" and the "?". An "*" will match zero or more characters and the "?" will match exactly one.Drive names and paths may be specified with the filename. There may not be any wildcards used for the drive or path, but the filename may still contain wildcards. A drive letter need not be specified with the path or the path need not be specified with the drive. The "h" option will stop tape recovery after one file is recovered, regardless of the numbers of files specified. The "n" option is the no overwrite option. It will not allow a file from tape to overwrite an existing file on disk if the names match. The "p" option restores files to the directory they were in when they were saved. If the directory does not exist EXRCVR will try to create it. If the directory can not be created it is ignored. All files are saved to the current drive unless the "s" option is used (see below for "s" option). If the "p" option is not used, the default directory is the current directory. Appendix A The "q" option quits EXRCVR. The "r" option will rewind the tape before displaying file names or recovering files. The "s" option will recover files writing them to the drive they were on at the time they were saved. If the "s" option is not used the default is the current drive. The "t" option is the time option. When used, if the name of a file on tape matches one on disk, the dates are compared. If the file on tape is most recent, the file on disk is overwritten. Otherwise the file on tape is not written. The "u" option resets all the options to the default. It will not remove the file names and patterns entered by using the "e" option. To remove filenames and patterns the user must quit EXRCVR and start over. The "w" option writes a directory listing of the tape to a file called 'DIR.LST". This option can only be used when the "d" option is specified. After the user selects the parameters, the user must press the ESCAPE key before EXRCVR will begin processing. EXRCYR Using the Command Line. . .............. . . .... To use EXRCVR from the command line form, the user must lype EXRCVR at the DOS prompt followed by a list of parameters. The order of the parameters will not affect the way EXRCVR recovers files. C:\>EXRCVR [-options) [file names ... ) [file patterns ... ] The parameters are the options, file names and file patterns. If an incorrect option is chosen a listing of the usage will be displayed. If no parameters are specified EXBACK will assume the user wants to run the program in menu form. The "d" option is used to display the names of the files on the tape. It displays all file names from the current position of the tape unless the rewind option is also used. If the rewind option is also used then the names of all files on the tape are displayed. When the display option is used no files will be written to disk. The "h" option will stop tape recovery after one file is recovered, regardless of the numbers of files specified. The "n" option is the no overwrite option. It will not allow a file from tape to overwrite an existing file on disk if the names match. The "p" option restores files to the directory they were in when they were saved. If the directory does not exist EXRCVR will try to create it. If the directory can not be created it is ignored. All files are saved to the current drive unless the "s" option is used (see below for "s" option). If the "p" option is not used, the default directory is the current directory. The "r" option will rewind the tape before displaying file names or recovering files. The "s" option will recover files writing them to the drive they were on at the time they were saved. If the "s" option is not used the default is the current drive. Appendix A The "" option is the time option. When used, if the name of a file on tape matches one on disk, the dates are compared. If the file on tape is most recent, the file on disk is overwritten. Otherwise the file on tape is not written. The "w" option writes a directory listing of the tape to a file called 'DIR.LST". This option can only be used when the "d" option is specified. If no file name(s) and/or pattern(s) are specified, no files will be recovered. Drive names and paths may be specified with the filename. There may not be any wildcards used for the drive or path, but the filename may still contain wildcards. A drive letter need not be specified with the path or the path need not be specified with the drive.