CCSD3ZF0000100000001NJPL3IF0PDSX00000001                                      
PDS_VERSION_ID                      = PDS3                                    
RECORD_TYPE                         = FIXED_LENGTH                            
RECORD_BYTES                        = 80                                      
OBJECT                              = TEXT                                    
  PUBLICATION_DATE                  = 1992-01-15                              
  NOTE                              = "Description of the Macintosh           
                                       II image display software."            
END_OBJECT                          = TEXT                                    
END                                                                           
                                                                              
                      Macintosh NIH IMAGE Software                            
                                                                              
This directory contains NIH Image, a public domain program written by         
Wayne Rasband of the National Institutes of Health.  This version of NIH      
Image has been modified to directly read images with PDS (Planetary Data      
System) labels (such as the files which end in '.LBL') on the Magellan        
CD-ROMs or '.IMG' and '.IBG' in other collections).  It will also             
directly read VICAR format images which are found on Magellan and             
Galileo Imaging CD-ROMs (labelled '.IMG').  It will also read SOME            
Compuserve GIF format images, specifically, the color images on MDIM          
Volume 14.                                                                    
                                                                              
When using System 6 image should be run under Finder for best results.        
When running under multifinder, the memory allocated to Image should be       
set as high as possible (at least 9000K to display an FMAP tile), using       
the Macintosh 'Get Info' command in the 'File' menu.                          
                                                                              
Image has a preferences file which sets certain display parameters.The        
preference settings are found in the 'Other' menu.  You should make sure      
the 'Invert Y Coordinates' box is checked in your preference settings.        
The 'Invert Displayed Pixel Values' box should NOT be checked.                
                                                                              
Image normally works with a gray scale palette using 0 as white and 255       
as black.  This version has been modified to use 1 as black and 254 as        
white, with 0 and 255 reserved, and set to white and black respectively.      
When PDS images are loaded any samples with value 0 are set to 1 and          
samples with value 255 are set to 254.  Most of the operations which          
modify pixel values (remove noise, sharpen, etc) have been modifed to         
work in the range 1 to 254.  As a result of these modifications some          
palette operations may give unpredictable results and some gray level         
settings will make the screen display (menu bars, etc) hard to read.          
                                                                              
The 'values' status display has been modified to show both the x,y            
coordinates and the latitude and longitude of the cursor position for         
data sets which have map projection label information (such as the            
Magellan and Digital Image Map CD-ROMs).  The data value at the cursor        
position is now given both as a pixel value and also in geophysical           
terms, if such conversions are specified in the labels.  For example,         
the Mars Digital Topographic Map displays the scaled altitude value in        
meters. NOTE:  The Compuserve GIF format images on Volume VO_2014 do          
not contain coordinate information thus the values display will not show      
latitude and longitude for these images.                                      
                                                                              
When loading 16 bit images, the low and high samples are used to scale        
the output between 1 and 254.  To set a fixed scale (for use with Pre-        
Magellan lunar images for example), select IMPORT in the FILE menu, and       
click on the edit button.  Enter the low and high values for scaling          
then click CANCEL.  Now open the 16-bit image and values will be scaled       
in the desired range.