I make a lot of animations in Cinema 4D, and I usually render those animations out as PNG sequences to then be used in After Effects. Since the renders take a while, I usually keep these PNG sequences even after the project is finished in case I need to come back to it.
Naturally, these PNG files can take up a lot of space. I’ve been looking into lossless video codecs to compress them, and have had some success (in other words, the lossless .mp4 file I get is much smaller than all the original PNG files themselves) with ffmpeg’s libx264rgb, but only for 24-bit RGB images. In other words, when I have animations with alpha channels, or the times when I export 8-bit depth channels, that codec doesn’t suffice (libx264 doesn’t support alpha and the .mp4 file created from the 8-bit png files is usually bigger than original PNG files themselves).
How do you store your PNG sequences for archival purposes, specifically 8-bit PNGs or those with alpha channels? Saving space on disk is my primary concern, and storing them losslessly is ideal.