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Originally Posted by mzso
Yeah, it feels like most of the complexity of present codecs is spent on catering to blocks and deblocking.
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Well, they ARE block-based codecs! New codecs are adding LOTS of knobs around block sizes and deblocking modes.
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I think alternative approaches are sorely under-researched. Not much effort was put into wavelets, even less into Daala's overlapped transformation before it was dopped.
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That is one of the challenges with any radically new technology. We have decades and millions of engineer-hours of experience optimizing around DCT-like block-based encoding. Even if a fundamentally new transform had a lot more potential, its initial implementations would have to compete against all the refinement of the current architectures. And it's very hard to estimate how well a basic technology will pan out. Wavelet-based video codecs were "obviously" the future, until actual real-world implementations went splat.
If we started with J2K instead of JPEG, and had all the motion estimation work done based around wavelets, hundreds of PhDs and developers could have found the magic way. And then someone with a crazy block-based codec idea would have run out of funding at just full-pel motion search, and we'd say "yeah, blocks were kind of interesting, but just never proved to be competitive."