.HELP                                                                         
                                                                              
The following commands are available :                                        
BATch        . . . .  to execute a batch command file                         
BRIghten     . . . .  add n to each DN value                                  
BROwse       . . . .  to display multiple files                               
CD           . . . .  MSDOS change directory command                          
COPy         . . . .  copy image to an internal buffer                        
CURsor       . . . .  to move the cursor around                               
DARken       . . . .  subtract n to each DN value                             
DIR          . . . .  MSDOS directory command                                 
DISplay      . . . .  to display the image                                    
ENHance name . . . .  filter the image                                        
ERAse        . . . .  to erase the display                                    
EXIt or QUIt . . . .  to exit from the program                                
FILe         . . . .  to specify the name of the image                        
HIStogram    . . . .  to display the histogram of the image                   
LABel        . . . .  to show image label                                     
LOG          . . . .  to save commands to a text file                         
MASk         . . . .  to mask off pixels in the image                         
MENu         . . . .  to invoke menu list                                     
MERge        . . . .  to combine internal buffers                             
NEGative     . . . .  to photo negative the image                             
OVErlay      . . . .  to draw grid lines on image                             
PALette      . . . .  to adjust the palette for the display                   
PERspective  . . . .  to display a pseudo-3D plot of the image                
PLOt         . . . .  to display and plot spectral data                       
PROfile      . . . .  to plot a profile of the image                          
REFresh      . . . .  to refresh the image plane                              
ROTate       . . . .  to rotate a piece of the image                          
SAVe         . . . .  to save the image display to a file                     
SET          . . . .  to set display options                                  
SLAnt        . . . .  displays the image slanted left/right                   
STRetch      . . . .  to do a linear gray scale stretch                       
SYStem       . . . .  to execute MSDOS commands                               
TEXt         . . . .  to place text on screen                                 
TYPe         . . . .  MSDOS type command                                      
WINdow       . . . .  to mark of a subimage on the display                    
                                                                              
Only the capitalized letters are required for the command.                    
The commands take optional keywords and values.                               
   The syntax is: COMMAND  KEY1=VAL1  KEY2 VAL2  . . .                        
Type 'HELP command' for help on a particular command.                         
.FILE                                                                         
FILE takes a required string value, i.e. the file name                        
FILE without filename enters file prompt mode                                 
FILE with a filename mask enters file prompt mode with only the               
     matching filenames                                                       
FILE also takes the following keyword:                                        
                                                                              
NOMemory     forces FILE to read the image from disk, even if the             
             image is already in XMS memory                                   
.DISPLAY                                                                      
DISPlay takes the following keywords:                                         
                                                                              
SUBsample    a positive integral subsampling factor                           
ZOOm         a positive integral zoom factor                                  
CENter       to display area around cursor                                    
AUToset      to automatically set dnlow and dnhigh to some                    
             percent n (def. 5 percent), based on histogram                   
NL NS        number of lines and samples to display in image                  
SL SS        starting line and sample in image                                
LEFT RIGHT   move starting sample left or right from previous                 
UP DOWN      move starting line up or down from previous                      
DSL DSS      starting line and sample on display                              
FLIp         flips the image top-to-bottom                                    
SOUrce       displays the source file, if given in the label for              
             Mars MDIM and Magellan F-MIDR only                               
NOPrompt     command line prompt is not displayed                             
.ERASE                                                                        
ERAse takes no parameters                                                     
.SET                                                                          
SET takes the following keywords :                                            
                                                                              
DNLOw  DNHIgh   the DN range to compress into display pixel                   
                Use no parameters to see the current values                   
BROwse fname    sets the default filename for use with BROWSE                 
SELect fname    sets default filename for use with BROWSE SELECT              
PALette dir     sets default palette directory name for use with              
                PAL LOAD command                                              
NS = n          sets the number of samples/line for display                   
SWAP            swaps bytes when reading the image (>8 bits)                  
UNSWAP          resets SWAP, so bytes aren't swapped                          
REFRESH ON      turns on the refresh buffer                                   
REFRESH OFF     turns off the refresh buffer                                  
DELay ON        for batch files - pauses before executing a line              
DELay OFF       for batch files - no pause before executing a line            
PROmpt ON       for batch files - enables display of each command             
PROmpt OFF      for batch files - disables display of each command            
                                                                              
DISplay vname   changes the display type to the one specified.                
                Standard graphics modes supported:                            
                  CGA     (640x200x2)    EGA     (640x350x16)                 
                  EGA480  (640x480x16)   VGA320  (320x200x256)                
                  VGA     (640x480x16)                                        
                                                                              
                Super VGA supported for the following:                        
                 ATI640      (640x480x256) - ATI VGA Wonder Board             
                 ATI800      (800x600x256) - ATI VGA Wonder Board             
                 ATI1024     (1024x768x16) - ATI VGA Wonder Board             
                 EVGA512     (512x480x256) - Everex Board                     
                 EVGA640     (640x480x256) - Everex Board                     
                 ORCHID      (640x480x256) - Orchid Board                     
                 ORCHID800   (800x600x256) - Orchid Board                     
                 ORCHID1024 (1024x768x256) - Orchid Board                     
                 PARADISE    (640x400x256) - Paradise Board 256K              
                             (640x480x256) - Paradise Board 512K              
                 TRIDENT     (800x600x256) - Trident SVGA Boards              
                 PGA         (640x480x256) - PGA Board                        
 Use the DOS SET command before starting IMDISP to set the                    
 default display type. EG: SET IMDISP=VGA will start up in VGA                
 mode.                                                                        
.HISTOGRAM                                                                    
HISTogram takes the following keywords :                                      
                                                                              
SUBsample    a integral subsample factor for speed                            
NL NS        number of lines and samples from image                           
SL SS        starting line and sample in image                                
CENter       do histogram on displayed portion of image                       
VOY          Use histogram from standard PDS Voyager image                    
VIK          Use histogram from standard PDS Viking image                     
COL          draw histogram using current color settings                      
.PALETTE                                                                      
PALette takes the following keywords :                                        
                                                                              
EDIt = n    to interactively adjust n color palette using the                 
            arrow keys on numeric keypad:                                     
             left(4) and right(6) move to different palette                   
             color, ^left and ^right move to colors in larger                 
             steps, HOME and END move to the beginning/end                    
             colors, up(2), down(8) to increment/decrement all                
             colors, letters R, r, G, g, B, b to incr/decr the                
             color, invert the palette with x or X, scroll with S             
             or s, and . or carriage return to end.                           
PSeudo color    PS = 0  for default palette                                   
                PS = 1  for gray scale palette                                
                PS = 2  IBM EGA palette                                       
                PS = 3  Redorange  PS = 4 Prism                               
                PS = 5  Topo       PS = 6 Contour                             
                PS = 7  BGRY       PS = 8 Glasses1                            
                PS = 9  Glasses2   PS =10 Perspective                         
SAVe = file     saves palette in text file                                    
LOAd = file     loads palette from file, if no file is blank,                 
                then prompt mode is entered                                   
DISplay         displays the current palette on the screen                    
ERAse           erases the current palette from the screen                    
CYCle number    Cycle color palette, S or s saves the palette                 
                CYC = 0 Blink         CYC = 1 Blink 4 times                   
                CYC = 2 Rotate left   CYC = 3 Rotate right                    
                CYC = 4 Rotate+random CYC = 5 Random                          
                CYC = 6 Double rotate CYC = 7 Random swap                     
                FAST    delay .1 seconds between cycles                       
                        instead of the default .3 seconds                     
                TIME n  to cycle for n seconds                                
.STRETCH                                                                      
STREtch takes the following keywords :                                        
                                                                              
LOw, HIgh     the low and high DN values of the stretch                       
     e.g.  STRET HI=128     for a stretch between 0 and 128                   
.CURSOR                                                                       
CURSor takes the following keywords:                                          
                                                                              
DSL, DSS      place the cursor at the specified display line and              
              sample location                                                 
                                                                              
Use the mouse or numeric keypad to move the cursor around, '-'                
 and '+' to change the cursor step size, and '.' or carriage                  
 return to end.                                                               
.PROFILE                                                                      
PROFile takes no parameters                                                   
Use the mouse or numeric keypad to move the cursor around, '-'                
 and '+' to change the cursor step size, '.' or carriage return               
 to select the first and second points                                        
.REFRESH                                                                      
REFResh takes no parameters                                                   
Redisplays the images from the refresh buffer and erases any                  
graphics currently on the screen.                                             
.BATCH                                                                        
BATch takes the following keywords :                                          
                                                                              
filename     filename of batch command file                                   
.SAVE                                                                         
SAVe takes the following keywords :                                           
                                                                              
filename     filename of image to save. If the filename has the               
             extension GIF, the file will be saved in GIF format.             
             Be patient - GIF takes time.                                     
REFRESH      saves the screen to the refresh buffer                           
NL NS        number of lines and samples to save                              
SL SS        starting line and sample to save                                 
BP           number of bits per pixel in output image                         
.DOS                                                                          
The following MSDOS commands are supported:                                   
                                                                              
drive letter:  Change default drive to specified letter                       
CD    path     MSDOS change directory command                                 
DIR   mask     MSDOS directory command                                        
TYPe  filename MSDOS type command                                             
SYStem or >    Spawns an MSDOS process                                        
SYStem name    executes program name                                          
.MENU                                                                         
MENu takes the following keywords :                                           
                                                                              
filename     filename of menu list file                                       
.LABEL                                                                        
LABel prints the label for the current PDS or FITS                            
format image.                                                                 
.TEXT                                                                         
TEXt takes the following format :                                             
                                                                              
LINe         line number to position text at                                  
SAMple       sample number to position text at                                
TEXT         'text to type out on screen' <cr>                                
.OVERLAY                                                                      
OVErlay takes the following keywords :                                        
                                                                              
MAXLAT       the upper left latitude of the current image                     
MAXLON       the upper left longitude of the current image                    
LEGend       draw a legend with the current color assignments                 
DN           the dn value to use for drawing grid lines                       
.BROWSE                                                                       
BROwse takes the following keywords :                                         
                                                                              
mask         a wildcard (ie. *.IMG) to select files to browse                 
SIZE         the size to use for displaying multiple images                   
SUB          a subsampling factor to use to display images ie.                
             'SUB 2' scales the image to half size                            
AUToset      to automatically set dnlow and dnhigh to some                    
             percent n (def. 5 percent), based on histogram                   
NOLabel      do not put the filename label on displayed images                
DNLow DNHigh sets the DN range for all images (see SET)                       
PAUse n      pauses display for n seconds when the screen gets full           
ALL          searches all subdirectories in addition to the                   
             current directory                                                
SELect       interactively selects files as they are being                    
             displayed and writes the filenames out to a select               
             file                                                             
FILe fname   select files to browse from a file instead of using              
             a mask                                                           
.PLOT                                                                         
PLOt takes the following keywords :                                           
                                                                              
LIN n      plot line n of the image (2-D file only)                           
SYMbol x   draw the plot using character x instead of a line                  
ZOOm       prompt user to zoom the plot                                       
OVErlay    overplot - do not erase the current plot                           
CENter     plot the image line containing the cursor                          
MAX n      set the maximum value in the plot                                  
MIN n      set the minimum value in the plot                                  
COLor n    use DN value n to plot the data                                    
SPEctral   analyze the plot of a spectrum                                     
.SERIAL                                                                       
SERial takes the following keywords :                                         
                                                                              
INIt               initialize the serial port                                 
COM  n             set COMn as the serial port to use                         
BAUd n             set the baud rate to n                                     
COMmand 'string'   write 'string' out the serial port                         
.PRINT                                                                        
PRInt takes the following keyword :                                           
                                                                              
TEK4693      use the Tektronix 4693DX driver                                  
.NEGATIVE                                                                     
NEGative takes no parameters                                                  
.BRIGHTEN                                                                     
BRIghten n  adds n to every pixel in the image                                
            The default is 10% of the total range, i.e., 2 for a              
            16 color display, 26 for a 256 color                              
.DARKEN                                                                       
DARken n    subtracts n from every pixel in the image                         
            The default is 10% of the total range, i.e., 2 for a              
            16 color display, 26 for a 256 color                              
.ENHANCE                                                                      
ENHance takes the following keywords:                                         
                                                                              
BAAlke         applies a custom filter developed by Ron Baalke                
CONvolution n  applies one of 2 weighted 3x3 filter to the image              
EDGe n         applies one of 4 3x3 edge enhancement filters                  
LOG n          applies a logarithmic filter to the image                      
MEAn n         applies one of 3 mean filters to the image                     
MEDian         applies a 3x3 median filter to the image                       
POWer n        applies an exponential filter to the image                     
STAir n        applies a stairstep smoothing to the image                     
SMEar          applies a smearing filter to the image                         
UNSharp        applies an unsharp mask filter to the image                    
SCReen         applies the filter only to the image on the                    
               screen, instead of the entire image                            
.SLANT                                                                        
SLAnt takes the following keywords:                                           
                                                                              
LEFt         displays the image slanted to the left                           
RIGht        displays the image slanted to the right (default)                
SCReen       slants the image currently on the screen                         
.LOG                                                                          
LOG takes the following keywords:                                             
                                                                              
ON           saves entered commands to the file IMDISP.LOG                    
FILe name    saves entered commands to the file named                         
OFF          closes the log file (same as CLOse)                              
CLOse        closes the log file (same as OFF)                                
.PERSPECTIVE                                                                  
PERspective takes the following keywords:                                     
                                                                              
SL n         starting line of the image                                       
SCR          reads image from the screen buffer                               
.COPY                                                                         
COPy uses buffers named A through Z.  COPy has these forms:                   
                                                                              
COPy buffer [FILE]  copies last displayed image to the buffer                 
                    specified (may be a disk file                             
                                                                              
COPy source TO buffer [FILE]  where source can be SCREEN or                   
                              another buffer                                  
.MERGE                                                                        
MERge combines buffers or images.  MERge has these forms:                     
                                                                              
MERGE buffer  Merge last displayed image with the buffer named                
              and display the result                                          
                                                                              
MERge source1 [scale1] WITH source2 [scale2] [TO buffer] [FILE]               
        to perform image arithmetic                                           
.MASK                                                                         
MASk substitutes a value for all pixels above or below a                      
     specified value.  MASk takes the following keywords:                     
                                                                              
LO n     sets all pixels with a DN less than n to 0                           
HI n     sets all pixels with a DN greater than n to 255                      
WITh n   sets the pixels to value n instead of the default                    
.WINDOW                                                                       
WINdow  sets the limits of a subimage by marking out a box on the             
        screen. WINdow takes the following keywords:                          
                                                                              
CANcel  sets the default back to the entire screen                            
L1      sets the first line of the window                                     
L2      sets the last line of the window                                      
S1      sets the first sample of the window                                   
S2      sets the last sample of the window                                    
.ROTATE                                                                       
ROTate  n  rotates the image or subimage through the specified                
           angle. ROTate takes the following keywords:                        
                                                                              
SCReen     rotates the screen, rather than the entire image                   
CLIp       trims off pieces of the image off the screen                       
NOFill     don't blank out the empty parts of the result                      
.OPTIONS                                                                      
   Within this command summary listing, brackets ([]) indicate                
optional parameters or keywords.  Filename is the name of a file              
in the current directory or a fully qualified filename which can              
include drive letter and pathname.  Directory name is an MS-DOS               
directory path specification, a valid directory mask a                        
specification containing wild card characters (*, ?) per MS-DOS               
rules for wildcard use in the DIRECTORY command.  The symbol "n"              
is used to indicate an integer value.                                         
                                                                              
  BATCH        [filename]                                                     
  BRIGHTEN     [n]                                                            
  BROWSE       [directory mask] [SIZe n] [SUB n] [NOLabel]                    
               [DNLOw n] [DNHIgh n] [PAUse n] [ALL] [SELect]                  
               [FILe] [BUFFERS] [AUToset n]                                   
  CD           [directory name] [..]                                          
  CHDIR        [directory name] [..]                                          
  COPY         [buffer [TO buffer]] [FILE]                                    
  CURSOR       [DSL n] [DSS n]                                                
  DARKEN       [n]                                                            
  DIRECTORY    [directory mask] [/w]                                          
  DISPLAY      [SUB n] [SL n] [SS n] [NL n] [NS n] [BP n]                     
               [CENTer] [DSL n] [DSS n] [ZOOm] [FLIP] [NOPrompt]              
               [NOMemory] [AUToset] [SOUrce] [CURsor] [buffer]                
  ENHANCE      [BAAlke] [CONvolution n] [EDGe n] [HIGh n]                     
               [HIStogram] [LOG n] [MEAn n] [MEDian] [POWer n]                
               [STAir n] [SMEar] [SCReen] [UNSharp]                           
  ERASE        [REFRESH] [buffer]                                             
  EXIT         [NOClear]                                                      
  FILE         [filename[.GIF]] ["CD:mm:ss:bb"] [NOMemory]                    
  HELP         [command name]                                                 
  HISTOGRAM    [SUB n] [SL n] [SS n] [NL n] [NS n] [BP n]                     
               [CENter] [VOYager] [VIKing] [buffer]                           
  LABEL                                                                       
  LOG          [ON] [FILe filename] [CLOse] [OFF]                             
  MASK         [LO n [WITH n]] [HI n [WITH n]]                                
  MENU         [filename]                                                     
  MERGE        [buffer [scale] [WITH buffer [scale] [TO buffer]]]             
               [FILE]                                                         
  NEG                                                                         
  OVERLAY      [MAXLAT n] [MAXLON n] [MINLAT n] [MINLON n] [LEGend]           
  PALETTE      [EDIT n] [PS n] [LOAd filename] [SAVe filename]                
               [DISplay] [ERAse] [CYC n [FAST] [TIME n]]                      
  PERSPECTIVE  [SL n] [SCR]                                                   
  PLOT         [LINE n] [SYMBOL x] [COLOR n] [MAX n] [MIN n]                  
               [OVERLAY] [ZOOM] [SPECTRAL]                                    
  PROFILE                                                                     
  QUIT         [NOClear]                                                      
  REFRESH                                                                     
  ROTATE       [n] [SCReen] [NOFill] [CLIp]                                   
  SAVE         filename[.GIF] [FORmat fmt] [SL n] [SS n] [NL n]               
               [NS n] [BP n] [REFRESH]                                        
  SET          [DNLO n] [DNHI n] [BROwse filename] [DIS name]                 
               [NS n] [PAL dir] [REFresh ON/OFF] [DELay ON/OFF]               
               [PROmpt ON/OFF] [BUFFERS dir]                                  
  SLANT        [RIGht] [LEFt]                                                 
  STRETCH      [LO n] [HI n]                                                  
  SYSTEM       [MS-DOS command]                                               
  TEXT         [LINe n] [SAMple n] "text" or 'text' [NOPrompt]                
  TYPE         filename                                                       
  WINDOW       [CANcel] [S1 n] [L1 n] [S2 n] [L2 n]                           
                                                                              
