NAME

       compare  -  mathematically  and  visually annotate the difference between an image and its
       reconstruction.

SYNOPSIS

       compare-im6.q16 input-file input-file [options] output-file

OVERVIEW

       The compare-im6.q16 program is a member of the  ImageMagick-ims6.q16(1)  suite  of  tools.
       Use  it  to  mathematically  and visually annotate the difference between an image and its
       reconstruction.

       For   more   information   about   the   compare   command,   point   your   browser    to
       file:///usr/share/doc/imagemagick-6-common/html/www/compare.html (on debian system you may
       install the imagemagick-6 package) or http://imagemagick.org/script/compare.php.

DESCRIPTION

       Image Settings:
         -alpha option        on, activate, off, deactivate, set, opaque, copy
                               transparent, extract, background, or shape
         -authenticate value  decrypt image with this password
         -background color    background color
         -channel type        apply option to select image channels
         -colorspace type     alternate image colorspace
         -compose operator    set image composite operator
         -compress type       type of pixel compression when writing the image
         -decipher filename   convert cipher pixels to plain pixels
         -define format:option
                              define one or more image format options
         -density geometry    horizontal and vertical density of the image
         -depth value         image depth
         -dissimilarity-threshold value
                               maximum distortion for (sub)image match
         -encipher filename   convert plain pixels to cipher pixels
         -extract geometry    extract area from image
         -format "string"     output formatted image characteristics
         -fuzz distance       colors within this distance are considered equal
         -gravity type        horizontal and vertical text placement
         -identify            identify the format and characteristics of the image
         -interlace type      type of image interlacing scheme
         -highlight-color color
                              emphasize pixel differences with this color
         -limit type value    pixel cache resource limit
         -lowlight-color color
                              de-emphasize pixel differences with this color
         -mask filename       associate a mask with the image
         -metric type         measure differences between images with this metric
         -monitor             monitor progress
         -passphrase filename get the passphrase from this file
         -profile filename    add, delete, or apply an image profile
         -quality value       JPEG/MIFF/PNG compression level
         -quiet               suppress all warning messages
         -quantize colorspace reduce colors in this colorspace
         -regard-warnings     pay attention to warning messages
         -repage geometry     size and location of an image canvas
         -respect-parentheses settings remain in effect until parenthesis boundary
         -sampling-factor geometry
                              horizontal and vertical sampling factor
         -seed value          seed a new sequence of pseudo-random numbers
         -set attribute value set an image attribute
         -similarity-threshold value
                               minimum distortion for (sub)image match
         -size geometry       width and height of image
         -subimage-search     search for subimage
         -synchronize         synchronize image to storage device
         -taint               declare the image as modified
         -transparent-color color
                              transparent color
         -type type           image type
         -verbose             print detailed information about the image
         -virtual-pixel method
                              virtual pixel access method

       Image Operators:
         -brightness-contrast geometry
                              improve brightness / contrast of the image
         -distort method args
                               distort images according to given method and args
         -level value         adjust the level of image contrast
         -resize geometry     resize the image
         -rotate degrees      apply Paeth rotation to the image
         -separate            separate an image channel into a grayscale image
         -trim                trim image edges
         -write filename      write images to this file

       Image Sequence Operators:
         -crop geometry       cut out a rectangular region of the image

       Image Stack Operators:
         -delete indexes      delete the image from the image sequence

       Miscellaneous Options:
         -debug events        display copious debugging information
         -help                print program options
         -log format          format of debugging information
         -list type           print a list of supported option arguments
         -version             print version information

       By default, the image format of `file' is determined by its magic number.   To  specify  a
       particular  image format, precede the filename with an image format name and a colon (i.e.
       ps:image) or specify the image type as  the  filename  suffix  (i.e.  image.ps).   Specify
       'file' as '-' for standard input or output.

       Two  images  are  considered similar if their difference according to the specified metric
       and fuzz value is 0, with the exception of the normalized cross correlation metric  (NCC),
       where  two images are considered similar when their normalized cross correlation is 1. The
       default metric is NCC.

       The compare program returns 2 on error, 0 if the images are similar, or a value between  0
       and 1 if they are not similar.

SEE ALSO

       ImageMagick-im6.q16(1)

COPYRIGHT

       Copyright  (C)  1999-2020 ImageMagick Studio LLC. Additional copyrights and licenses apply
       to this software, see file:///usr/share/doc/imagemagick-6-common/html/www/license.html (on
       debian     system     you     may     install     the     imagemagick-6     package)    or
       http://imagemagick.org/script/license.php