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Daala progress update

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Re: Daala progress update

#11

Post by aidenn0 »

bigboat wrote: post #10
aidenn0 wrote: post #6

I 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.

I did not see detail in the JPEG that was not present in the h.265; a few regions in the grass still look slightly better, since they have more noise and less blur, and that's more pleasant to the eye in high-frequency areas.

Also note that there is more detail in the h.265 than the JPEG where the trees meet the sky.

Re: Daala progress update

#12

Post by TD-Linux »

nitrogen wrote: post #5
quink wrote: post #3

Earlier quoted context omitted.

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.

Vidyo uses an implementation of H.264 SVC, I believe. But in general it's not been widely adopted. SVC generally has worse compression than normal H.264, so for streaming it makes more sense just to store multiple encodes at different qualities.

Re: Daala progress update

#13

Post by derf_ »

quink wrote: post #3
AceJohnny2 wrote: post #2

Interesting 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…

Bitrate peeling is not a design goal, no.

Re: Daala progress update

#14

Post by TD-Linux »

quink wrote: post #3
AceJohnny2 wrote: post #2

Interesting 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…

Daala uses wavelets in a few areas, but is largely a lapped DCT based codec. It's not especially suited for producing scalable bitstreams, at least not much more than any other codec. There's little demand for it right now, so we don't plan to include it as a feature.

However, if you have some interesting application of it, feel free to let us know!

Re: Daala progress update

#15

Post by nitrogen »

0x0 wrote: post #7

Applying an easing animation on the split screen comparison mouse drag was probably not the most user friendly idea.

Is it actually an animation? I assumed it was lag caused by redrawing each time the mouse moves and not ignoring queued mouse movements. Perhaps I assumed incorrectly.

Re: Daala progress update

#16

Post by nitrogen »

aidenn0 wrote: post #9
0x0 wrote: post #8

Earlier quoted context omitted.

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.

Apart from JPEG's blockiness and VP8's complete loss of detail, it looks like the main difference between codecs is which parts of the image have detail preserved. Some codecs preserve subtle sky texture at the expense of the trees, others do the opposite.

Re: Daala progress update

#17

Post by 0x0 »

nitrogen wrote: post #15
0x0 wrote: post #7

Applying an easing animation on the split screen comparison mouse drag was probably not the most user friendly idea.

Is it actually an animation? I assumed it was lag caused by redrawing each time the mouse moves and not ignoring queued mouse movements. Perhaps I assumed incorrectly.

I thought the BPG page earlier had a much more instant response, but it appears I remembered incorrectly because it behaves almost the same. My bad. http://xooyoozoo.github.io/yolo-octo-bugfixes/

Re: Daala progress update

#18

Post by derf_ »

nitrogen wrote: post #15
0x0 wrote: post #7

Applying an easing animation on the split screen comparison mouse drag was probably not the most user friendly idea.

Is it actually an animation? I assumed it was lag caused by redrawing each time the mouse moves and not ignoring queued mouse movements. Perhaps I assumed incorrectly.

12:37:59 no, the lag is intentional.

12:38:11 it seems wrong... but exact tracking felt worse.

Re: Daala progress update

#19

Post by IvyMike »

Charles Bloom has been discussing PVQ and Daala over on his blog. I am not an expert nor have I fully understood these articles, but they definitely look like interesting related reading.

http://cbloomrants.blogspot.com/2014/12/12-16-14-daala-pvq-e... http://cbloomrants.blogspot.com/2014_12_01_archive.html

Re: Daala progress update

#20

Post by Taek »

TD-Linux wrote: post #14
quink wrote: post #3

Earlier quoted context omitted.

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…

Daala uses wavelets in a few areas, but is largely a lapped DCT based codec. It's not especially suited for producing scalable bitstreams, at least not much more than any other codec. There's little demand for it right now, so we don't plan to include it as a feature. However, if you have some interesting application of it, feel free to let us know!

This isn't my direct area of expertise, so I apologize in advance if I am incorrect about anything.

Video streaming suffers from unstable connections, and varied throughputs. Some home connections can support high fidelity 1080p and others can just manage visibly degraded 480p.

Right now, either you have to store each resolution separately (which can be costly, esp. at 3x redundancy and esp. if your average video is only going to be watched a few hundred times e.g. YouTube), or you have to transcode on-the-fly, which is expensive for any sort of good compression rate.

As we move forward, p2p streaming is likely to be a lot more dominant. There are a few services already out there and a few more in development that have a lot of promise. P2p settings are even more sensitive to transcoding costs, as you'd rather have peers uploading in high parallelism, meaning each one would need to be transcoding.

I do believe that scalable bitstreams will be important, as they solve a lot of the problems.

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