A bit about next micro codec

Some time ago I mentioned that I’d stumbled upon a QuickTime sample encoded on NeXT using MicroWavelet codec which was used only there. I also expressed a regret of it being completely lost to time. And what do you know, it’s yet another situation where I’d be glad to be proven wrong—and I was (and I am). Apparently had I looked around for a bit longer, I would’ve discovered more samples and a decoder to boot. Apparently that decoder was a part of NeXTTime and not QuickTime, which is a completely different thing. And NeXTTime including that decoder could be found on OpenStep 4.x in particular. While I have not written a decoder for it yet, I’ve figured out enough details to talk about it. First of all, it’s a sort of several loosely-tied codecs (and I’m yet to figure out what makes it choose which decoding path to take). One of them is a simple wavelet codec with 8-bit coefficients and no additional compression, others are delta coding plus zero-run compression plus optional…