Daala progress update
people.xiph.org
Daala progress update
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Re: Daala progress update
#2Interesting to see they're also applying Daala to still images. It's a very different set of constraints and optimizations than video.
My first instinct was to wonder how it compared to Bellard's recently featured BPG image format [1], which achieves impressive quality at low sizes. Turns out you can check this by selecting "HEVC" in Xiph's image comparison, since that's the core method employed by BPG.
Re: Daala progress update
#3Interesting to see they're also applying Daala to still images. It's a very different set of constraints and optimizations than video. My first instinct was to wonder how it compared to Bellard's recently featured BPG image format [1], which achieves impressive quality at low sizes. Turns out you can check this by selecting "HEVC" in Xiph's image comparison, since that's the core method employed by BPG. [1] http://be…
And Daala is not fixed yet, so there's a good chance of further improvements a-coming. And it's likely to be relatively clean of patents and may enable a cross-everything royalty free implementation. But time will tell how MPEG LA will feel about that.
Edit: I'm also wondering, just in case any experts are around... with Daala's design seeming at first glance inherently more suitable for that kind of thing, lifting filters, wavelets and all, does that mean that we're more likely to see some hierarchical modulation/scalable video coding/bitrate peeling sooner rather than later?
Re: Daala progress update
#4Interesting to see they're also applying Daala to still images. It's a very different set of constraints and optimizations than video. My first instinct was to wonder how it compared to Bellard's recently featured BPG image format [1], which achieves impressive quality at low sizes. Turns out you can check this by selecting "HEVC" in Xiph's image comparison, since that's the core method employed by BPG. [1] http://be…
> Interesting to see they're also applying Daala to still images. It's a very different set of constraints and optimizations than video.
Video codecs have to encode keyframes, which is roughly the same problem as still images. Many still image codecs are modified intraprediction modes from video codecs. So it's really a subset[0] of the constraints and optimizations, not a totally different set.
It's also the case we've recently spent a lot of time working on intraprediction issues (and related topics). One reason for that is that the lapping filters make intraprediction very difficult compared to traditional codec designs.
Demo2[1] explains much of this difficulty in the context of a solution that we tried and had to abandon. The paint demo[2] explains another solution we tried, which also failed, but which is now the basis of a post-filtering technique.
[0] Modulo things like color format support, metadata, etc.
Re: Daala progress update
#5Interesting to see they're also applying Daala to still images. It's a very different set of constraints and optimizations than video. My first instinct was to wonder how it compared to Bellard's recently featured BPG image format [1], which achieves impressive quality at low sizes. Turns out you can check this by selecting "HEVC" in Xiph's image comparison, since that's the core method employed by BPG. [1] http://be…
And Daala is not fixed yet, so there's a good chance of further improvements a-coming. And it's likely to be relatively clean of patents and may enable a cross-everything royalty free implementation. But time will tell how MPEG LA will feel about that. Edit: I'm also wondering, just in case any experts are around... with Daala's design seeming at first glance inherently more suitable for that kind of thing, lifting f…
Has bitrate peeling been used in production by anybody? I got the impression that the bitrate peeling in Vorbis is never used, and that streaming providers will just encode multiple rates for a video and switch between them. It does sound like a cool concept, though.
Re: Daala progress update
#6I prefer the JPEG to the Daala in that one sample image; JPEG does have more artifacts, but Daala seems to preserve less detail.
For low-to-medium bitrate video that might be the correct tradeoff though.
[edit] H264 and H265 look like successive incremental improvements over JPEG in the direction I personally prefer; they reduce artifacts without losing detail.
Re: Daala progress update
#7Applying an easing animation on the split screen comparison mouse drag was probably not the most user friendly idea.
Re: Daala progress update
#8I prefer the JPEG to the Daala in that one sample image; JPEG does have more artifacts, but Daala seems to preserve less detail. For low-to-medium bitrate video that might be the correct tradeoff though. [edit] H264 and H265 look like successive incremental improvements over JPEG in the direction I personally prefer; they reduce artifacts without losing detail.
I think the sky looks much nicer in Daala, but the bushes look much more blurred.
Re: Daala progress update
#9I prefer the JPEG to the Daala in that one sample image; JPEG does have more artifacts, but Daala seems to preserve less detail. For low-to-medium bitrate video that might be the correct tradeoff though. [edit] H264 and H265 look like successive incremental improvements over JPEG in the direction I personally prefer; they reduce artifacts without losing detail.
I think the sky looks much nicer in Daala, but the bushes look much more blurred.
I agree; JPEG has more artifacts which is most noticeable in low-frequency areas, but preserves more detail in high-frequency areas.
All of the non-JPEG codecs seem to have greatly reduce artifacts in the low-frequency areas, but for some of them (VP8 in particular) it was at a significant loss of detail.
Re: Daala progress update
#10I prefer the JPEG to the Daala in that one sample image; JPEG does have more artifacts, but Daala seems to preserve less detail. For low-to-medium bitrate video that might be the correct tradeoff though. [edit] H264 and H265 look like successive incremental improvements over JPEG in the direction I personally prefer; they reduce artifacts without losing detail.
Did you compare h.265 with the original images? It trades a lack of artifacts for a fairly significant reduction in detail.