This archive contains a command line tool (pgmtool v. 0.6) for performing on PGM P5 and RAW grayscale images transformations including: resizing, cropping, changing bit depth or endianness, adding noise, softening.

This archive contains files:
* Win32 executable: pgmtool.exe
* C++ source code of the tool: pgmtool.cpp - main module, crc_32.cpp and crc_32.h - CRC32 routines by Gary S. Brown, rand.cpp and rand.h - ISAAC random number generator by Bob Jenkins
* this file (readme.txt)

Further description (the same will be outputted by the tool invoked with no arguments):


pgmtool v. 0.6, (c) 2015 Roman Starosolski, rstarosolski@polsl.pl

Perform transformations on PGM P5 and RAW grayscale images.

This software is intended for research purposes only; it is provided "as is"; author makes no warranty of any kind, either express or implied, with respect to this software.
This software uses CRC32 routines by Gary S. Brown and ISAAC random number generator by Bob Jenkins. 
This work was partially supported by POIG.02.03.01-24-099/13 grant: GeCONiI - Upper-Silesian Center for Scientific Computations.

Commandline syntax (fixed commandline order: -i switches, infilename, one or
no -t switch, one or no -o switch, outfilename):
   
    [-i:RAW:width:height[:bpp[:skip]]]  
                          RAW image dimensions, depth (default 16 bits)
                          and starting offset (default: 0)
    [-i:RAW:like:PGMP5filename]          
                          Load RAW image dimensions and depth from PGM P5 
                          file PGMP5filename, starting offset=0
    [-i:endian:Little|Big]              
                          endianness of the input file, default:BigEndian
   
    infilename            input file name with extension,
                          PGM P5 assumed if no -i:RAW specified,
                          pixel intensities assumed unsigned,
                          before inputting image pixels pgmtool reports:
                            ImgFileName     -image file name
                            ImgImageWidth   -width
                            ImgImageHeight  -height
                            ImgBYTEpp       -file Bytes per pixel
                            Imgbpp          -nominal bits per pixel
                            ImgLevelMax     -nominal maximum intensity
                            ImgBigEndian    -is image BigEndian?
                            ImgRaw          -is it RAW
                            ImgRawSkip:     -file offset of image data
                          after inputing image pgmtool reports:
                            minLevel	       -actual minimum intensity
                            maxLevel        -actual maximum intensity
                            numLevels       -actual number of intensities
                            bitsUsed        -word bits used by any pixel
                            H0              -memoryless entropy of pixels in
                                             bits, Bytes and bits per pixel
                            CRC32           -CRC32 checksum of pixels and
                                             pixels' Bytes (BigEndian assumed)
   
    [-t:noise:percent]    replace percent% [0, 100] of image pixels 
                          with noise of uniform distribution
    [-t:addnoise:percent] replace percent% of each pixel's intensity with
                          uniform noise
    [-t:soften:radius:centerweight:neighborweight] 
                          soften image by replacing each pixel with weigted 
                          average of that pixel (weight: centerweight) and 
                          neighbors in 8-neighborhood (weight of each: 
                          neighborweight) distant by no more than radius 
    [-t:downsize:times]   reduce image size, times in range [1, 100]
                          by averaging times x times pixel blocks 
    [-t:crop:x0:y0:newwidth:newheight]  
                          crop image, x0,y0 - top left corner
    [-t:reducedepth:newdepth]           
                          reduce depth right-shifting intensities, 
                          newDepth in range [1, InImgbpp)
    [-t:cropdepth:newdepth]             
                          reduce nominal depth keeping intensities, 
                          report error if intensity exceeds new nominal depth
    [-t:cropdepthlike:PGMP5filename]    
                          reduce nominal depth to depth of PGM P5 image
    [-t:cropclipdepth:newdepth]    
                          reduce nominal depth clipping too large intensities
                          to top of allowable range
    [-t:increasedepth:newdepth:mode]    
                          increase image depth, newdepth <= 16
                            mode=0 - nominal only, keeping intensities
                            mode=1 - nominal and left-shifting intensities
    [-t:negendian]        invert image endianness (Big<->Little)
    [-t:xorfile:xorfname] perform xor on image pixels with file xorfname 
                          containing BigEndian ImgBYTEpp-Byte unsigned numbers
                          whose bits exceeding Imgbpp are ignored
     
    [-o:RAW]              output image as RAW, otherwise PGM P5
    outfilename           output file name

Examples:

Soften lena.pgm, save as PGM
    pgmtool lena.pgm -t:soften:1:8:1 lena_s.pgm
Replace 10% of pixels in lena.pgm image with noise(uniform distribution), save resulting file as RAW
    pgmtool lena.pgm -t:noise:10 -o:RAW lena_n.raw
Input lena_n.raw RAW image assuming dimensions and depth as in lena.pgm, save as 16-bit BigEndian PGM
    pgmtool -i:RAW:like:lena.pgm lena_n.raw -t:increasedepth:16:0 lena_16.pgm
Convert BigEndian PGM image lena_16.pgm to LittleEndian RAW lena_16le.raw
    pgmtool lena_16.pgm -t:negendian -o:RAW lena_16le.raw
Just display information on lena.pgm image
    pgmtool.exe lena.pgm