The COMPRESS_ framework (_CMD, _DEPENDS) in image.bbclass is useful for more than compressing images but can generate checksums too, basically its a command to run on an image. Maybe we should rename it to reflect this.
There is a patch under review doing similar renaming: http://lists.openembedded.org/pipermail/openembedded-core/2016-June/122574.html It renames COMPRESSION* variables to CONVERSION*
The patchset is not going to be merged into M1. Moving to M2.
Shifted to M3 as latest patchset caused problems and haven't been merged.
sent patch for review as a part of the fix for bug 9076: http://lists.openembedded.org/pipermail/openembedded-core/2016-July/124384.html
Sent the fix again: http://lists.openembedded.org/pipermail/openembedded-core/2016-July/124519.html
merged to master: https://git.yoctoproject.org/cgit/cgit.cgi/poky/commit/?id=ff3a455ee84b91e797052760c8d4618109b54c63