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> I think you're eating into quality loss if you're getting 33%-25% size, most every benchmark puts it at about 50%-60% size for equal quality to h264. Do the

> I think you're eating into quality loss if you're getting 33%-25% size, most every benchmark puts it at about 50%-60% size for equal quality to h264. Do the benchmarks include animation? Perhaps flat surfaces like one sees in anime compress a lot better than average in x265?

zamadatix 8y ago
Often, oddly enough. Anime groups in particular are obsessive about bitdepth, quality, and file size to the point it's not hard to find comparisons of lossless compression in newer codecs. On the development and academic benchmarking side any comparison worth it's salt should have more than 5 different categories of video style. The paper linked in the article based their results on 20 different sequences, 3 or 4 of which looked to be animated.
- samplatt 8y ago
  One of the main reasons for the anime groups obsessing about the comparisons is that it's a lot easier to measure final quality on anime, with it's clearly-delineated artwork, instant transitions, and (comparatively) simple backgrounds.
  - IanCal 8y ago
    I would also have guessed that many approaches for video/image compression like assuming lots of nice smooth gradients without hard edges, and so flat shaded but detailed drawn things might fare badly.
    - GuB-42 8y ago
      Hard edges are difficult for the DCT/DST used in most video codecs. A wavelet-based codec would most likely be better suited. However, all modern codecs that I know of have directional intra prediction, which should be pretty effective in anime. Basically, what it does is that the decoder is able to follow lines with a variety of angles. There are other things that help compression in anime: static frames, large flat areas, lack of film grain in computer drawn animation.
BurningCycles 8y ago
I would guess so, but looking at Nyaa atleast, there seem to be very little content encoded in HEVC compared to h264, which seems weird given how the 'anime scene' saw adoption of x264 10bit which is not even hardware accelerated. With the supposed savings of HEVC versus h264, and the rather widespread HEVC hardware support in devices, I would have guessed that they would have embraced it at a larger scale by now. Will be interesting to see what happens with AV1.

zamadatix 8y ago

Often, oddly enough. Anime groups in particular are obsessive about bitdepth, quality, and file size to the point it's not hard to find comparisons of lossless compression in newer codecs. On the development and academic benchmarking side any comparison worth it's salt should have more than 5 different categories of video style. The paper linked in the article based their results on 20 different sequences, 3 or 4 of which looked to be animated.

samplatt 8y ago
One of the main reasons for the anime groups obsessing about the comparisons is that it's a lot easier to measure final quality on anime, with it's clearly-delineated artwork, instant transitions, and (comparatively) simple backgrounds.
- IanCal 8y ago
  I would also have guessed that many approaches for video/image compression like assuming lots of nice smooth gradients without hard edges, and so flat shaded but detailed drawn things might fare badly.
  - GuB-42 8y ago
    Hard edges are difficult for the DCT/DST used in most video codecs. A wavelet-based codec would most likely be better suited. However, all modern codecs that I know of have directional intra prediction, which should be pretty effective in anime. Basically, what it does is that the decoder is able to follow lines with a variety of angles. There are other things that help compression in anime: static frames, large flat areas, lack of film grain in computer drawn animation.

BurningCycles 8y ago

I would guess so, but looking at Nyaa atleast, there seem to be very little content encoded in HEVC compared to h264, which seems weird given how the 'anime scene' saw adoption of x264 10bit which is not even hardware accelerated. With the supposed savings of HEVC versus h264, and the rather widespread HEVC hardware support in devices, I would have guessed that they would have embraced it at a larger scale by now. Will be interesting to see what happens with AV1.