Check whether this filter does result in a smaller git repository

[rayrobdod]

Check whether this filter does result in a smaller git repository

[rayrobdod]

In theory, the benefit here is that this allows git to perform delta compressions. However, apparently git by default will not attempt any delta compression on any blob with a size greater than 512Mb. Which, at 32 bits per pixel is about a 1100-pixel square image. Not that most of the images I've seen in a repository are either larger in physical size or 32 bits per pixel.

[rayrobdod]

With pret/pokepinball (with master on 69a220a9efce3939147b8086af4bee3363c9f10f):

All variants have 6253 items after a git gc --aggressive --prune=NOW, which is a basic check that nothing was discarded

• The original repository has a size-pack of 2769
• Using filter-branch with pngout has a size-pack of 2754 (although pngout's algorithm doesn't seem to work well with tiny, 2-bit-depth images, resulting in a lot of Unable to compress further: copying original file)
• Using filter-branch with png-inflate has a size-pack of 2712