<imdoc>
<utils apps=compare>
<title>Compare</title>
<gm>
<sect NAME="compare">gm compare
</gm>
<im>
<sect NAME="comp-top">NAME
compare - compare two images.
</sect>
<format type=html>
<sect NAME="comp-contents">Contents

<dl>
<dt>
<a href="#comp-syno">Synopsis</a>
</dt>

<dt>
<a href="#comp-desc">Description</a>
</dt>

<dt>
<a href="#comp-exam">Examples</a>
</dt>

<dt>
<a href="#comp-opti">Options</a>
</dt>

</dl>
</format>
</sect>

<sect NAME="comp-syno">Synopsis

<p>
<s>gm compare</s> <s>[</s> <i>options</i> <s>... ]</s> <i>reference-image</i>
<s>[</s> <i>options</i> <s>... ]</s> <i>compare-image</i>
<s>[</s> <i>options</i> <s>... ]</s></p>

</sect>

<sect NAME="comp-desc">Description
</im>
<p>
<s>compare</s> compares two similar images using a specified statistical
method (see <s>-metric</s>) and/or by writing a difference image
(<s>-file</s>), with the altered pixels annotated using a specified
method (see <s>-highlight-style</s>) and color (see
<s>-highlight-color</s>).</p> <p><i>Reference-image</i> is the original
image and <i>compare-image</i> is the (possibly) altered version, which
should have the same dimensions as <i>reference-image</i>.</p>

</sect>

<sect NAME="comp-exam">Examples

<p>
To compare two images using Mean Square Error (MSE) statistical analysis
use:</p>

<pre>
    compare -metric mse original.miff compare.miff
</pre>

<p>
To create an annotated difference image use:</p>

<format type=man,tex>
<pre>
    compare -highlight-style assign -highlight-color purple \
      -file diff.miff original.miff compare.miff
</pre>
</format>
<format type=html>
<pre>
    compare -highlight-style assign -highlight-color purple -file diff.miff original.miff compare.miff
</pre>
</format>

</sect>
<back>

<!-- --------------------- Options ---------------------------------- -->

<sect NAME="comp-opti">Options

<p>
Options are processed in command line order. Any option you specify on
the command line remains in effect only for the image that follows.  All
options are reset to their default values after each image is read.</p>
<p>
For a more detailed description of each option, see
<gm>
Options, above.
</gm>
<im>
<format type=man,tex>
<i>GraphicsMagick(1)</i>.
</format>
<format type=html>
<a href="GraphicsMagick.html"><i>GraphicsMagick(1)</i></a>.
</format>
</im>
</p>

</utils>

<include file=brief_options.imdoc>

<utils apps=compare>
<p>
For a more detailed description of each option, see
<gm>
Options, above.
</gm>
<im>
<format type=man,tex>
<i>GraphicsMagick(1)</i>.
</format>
<format type=html>
<a href="GraphicsMagick.html"><i>GraphicsMagick(1)</i></a>.
</format>
</im>
</p>

</sect>
<im>
<back>

<format type=man>
<sect NAME="comp-also">SEE ALSO
<p>
GraphicsMagick(1),
animate(1),
compare(1),
conjure(1),
convert(1),
display(1),
identify(1),
import(1),
mogrify(1),
montage(1)
</p>
</sect>
</format>
</im>
</utils>
</imdoc>
