Some comments here about delta compression on image assets and compressed formats - this page from the Fossil SCM has a really interesting discussion of the issues involved: https://fossil-scm.org/home/doc/trunk/www/image-format-vs-re...
Looking at Fossil's delta code it uses 16 byte blocks and a sliding window when finding deltas:
https://fossil-scm.org/home/file?ci=trunk&name=src/delta.c&l...