The animated image you are talking about are probably animated GIFs. An animated GIF is a file valid under the GIF89a spec, which you can get some info about here .

The module Image::ParseGIF can break a GIF down into its component images and allow you to detect and reject animations.

use Image::ParseGIF;
$gif = new Image::ParseGIF ("image.gif") or die "failed to parse: $@\n
+";
print "Multiple parts\n" if $gif->parts > 1;
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