Comments say it&#x27;s based on this: <a href="https:&#x2F;&#x2F;github.com&#x2F;demouth&#x2F;DmImage&#x2F;blob&#x2F;master&#x2F;example&#x2F;sample_node&#x2F;animate&#x2F;GifMerge.class.php" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;demouth&#x2F;DmImage&#x2F;blob&#x2F;master&#x2F;example&#x2F;sampl...</a><p>Some of what you mentioned is already present there. Some other things are new. But they&#x27;re both terrifying...<p>Extra details: the rewrite into gifencoder happened in 2007, so gifmerge must be older than that (maybe 4.x times). The original license forbids modifying gifmerge without author&#x27;s approval - since this file doesn&#x27;t mention it at all, I doubt dmimage is legal.