compare(1) General Commands Manual compare(1)
NAME
compare - mathematically and visually annotate the difference between
an image and its reconstruction.
SYNOPSIS
compare input-file input-file [options] output-file
OVERVIEW
The compare program is a member of the ImageMagick(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/www/compare.html@EXTRA_DOC_DIR@ or
https://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 num-
ber. 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 normal-
ized cross correlation metric (NCC), where two images are considered
similar when their normalized cross correlation is 1. The default met-
ric 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(1)
COPYRIGHT
Copyright (C) 1999 ImageMagick Studio LLC. Additional copyrights and
licenses apply to this software, see file:///usr/share/doc/ImageMag-
ick-6/www/license.html@EXTRA_DOC_DIR@ or https://imagemag-
ick.org/script/license.php
ImageMagick Date: 2009/01/10 01:00:00 compare(1)