I don’t know the details of AV2, but going from h.265 to h.266, the number of angles for angular prediction doubled, they added a tool to predict chroma from luma, added the ability to do pixel block copies and a bunch of other techniques… And that’s just for intra predictions. They also added tons of new inter prediction techniques.
All of this requires a significant amount of extra logic gates/silicon area for hardware decoders, but the bit rate reduction is worth it.
For CPU decoders, the additional computational load is not so bad.
The real additional cost is for encoding because there’s more prediction tools to choose from for optimal compression. That’s why Google only does AV1 encoding for videos that are very popular: it doesn’t make sense to do it on videos that are seen by few.
We must be reaching the limit at which video codecs can only achieve better quality by synthesizing details. That's already pretty prevalent in still images - phone cameras do it, and there are lots of AI resizing algorithms that do it.
It doesn't look like AV2 does any of that yet though fortunately (except film grain synthesis but I think that's fine).
Please no. This is what jbig2 does for images and it’s a nightmare in my view, you can’t trust the result is not something totally different from the original [1]
I always thought the name AV1 was partly a play on/homage to AVI (Audio Video Interlace), but AV2 breaks that. Even if it’s meant to be embedded into other container formats such as MP4, there are files with the .av1 extension and there is a video/AV1 MIME type (and possibly a UTI?). Does this mean we now need to duplicate all that to .av2 and video/AV2? What about the AVIF file format?
Let's hope they get more things right 2nd time around. AOM will do Live Session on 20th of October: The Future of Innovation is Open [1].
May be more data and numbers. Including Encoding Complexity increase, decoding complexity. Hardware Decoder roadmap. Compliance and Test kits. Future Profile. Involvement and improvement to both AVIF the format and the AV2 image codec. Better than JPEG-XL? Are the ~30% BDRATE compared to current best AV1 encoder or AV1 1.0 as anchor point? Live Encoding improvements?
As a little experiment, I'd like you to set up your own little streaming service on a server and see how much bandwidth it uses, even for just a few users. It adds up extremely quickly, with the actual using being quite surprising.
At the higher prices, I'd have to agree with you. If you pay for the best you should get the best.
>the best picture quality I’ve ever seen was over 20 years ago using simple digital rabbit ears.
The biggest jump in quality was when everything was still analog over the air, but getting ready for the digital transition.
Then digital over the air bumped it up a notch.
You could really see this happen on a big CRT monitor with the "All-in-Wonder" television receiver PCI graphics adapter card.
You plugged in your outdoor antenna or indoor rabbit ears to the back of the PC, then tuned in the channels using software.
These were made by ATI before being acquired by AMD, the TV tuner was in a faraday cage right on the same PCB as the early GPU.
The raw analog signal was upscaled to your adapter's resolution setting before going to the CRT so you had pseudo better resolution than a good TV like a Trinitron. You really could see more details and the CRT was smooth as butter.
As the TV broadcaster's entire equipment chain was replaced, like camera lenses, digital sensors and signal processing they eventually had everything in place and working. You could notice these incremental upgrades until a complete digital chain was established as designed. It was really jaw-dropping. This was well in advance of the deadline for digital deployment, so the signal over-the-air was still coming in analog the same old way.
Eventually the broadcast signal switched to digital and the analog lights went out, plus the All-in-Wonder was not ideal with a cheap converter like analog TV's could get by with.
But it was still better than most digital TVs for a few years, then it took years more before you could see the ball in live sports as well as on a CRT anyway.
Now that's about all you've got for full digital resolution, live broadcasts from your local stations, especially live sports from a strong interference-free station over an antenna. You can switch between the antenna and cable and tell the difference when they're both not overly compressed.
The only thing was, digital engineers "forgot" that TV was based on radio (who knew?) so for the vast majority of "listeners" on the fringe reception areas who could get clear audio but usually not a clear picture if any, too bad for you. You're gonna need a bigger antenna, good enough to have gotten you a clear picture during the analog days. Otherwise your "clean" digital audio may silently appear on the screen as video, "hidden" within the sparse blocks of scattered random digital noise. When anything does appear at all.
I pirate blu-ray rips. Pirates are very fastidious about maintaining visual quality in their encodings. I often see them arguing over artifacts that I absolutely cannot see with my eyes.
Who does this benefit? Sounds like this stuff mainly benefits streaming providers and not users. We get to go through the whole rigamarole again where hardware is made obsolete because it doesn't support acceleration.
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[ 3.2 ms ] story [ 53.4 ms ] threadIs this just people being clever or is it also more processing power being thrown at the problem when decoding / encoding?
All of this requires a significant amount of extra logic gates/silicon area for hardware decoders, but the bit rate reduction is worth it.
For CPU decoders, the additional computational load is not so bad.
The real additional cost is for encoding because there’s more prediction tools to choose from for optimal compression. That’s why Google only does AV1 encoding for videos that are very popular: it doesn’t make sense to do it on videos that are seen by few.
It doesn't look like AV2 does any of that yet though fortunately (except film grain synthesis but I think that's fine).
[1]https://www.dkriesel.com/en/blog/2013/0802_xerox-workcentres...
If true, that would be amazing.
May be more data and numbers. Including Encoding Complexity increase, decoding complexity. Hardware Decoder roadmap. Compliance and Test kits. Future Profile. Involvement and improvement to both AVIF the format and the AV2 image codec. Better than JPEG-XL? Are the ~30% BDRATE compared to current best AV1 encoder or AV1 1.0 as anchor point? Live Encoding improvements?
[1] https://aomedia.org/events/live-session-the-future-of-innova...
I have a top-of-the-line 4K TV and gigabit internet, yet the compression artifacts make everything look like putty.
Honestly, the best picture quality I’ve ever seen was over 20 years ago using simple digital rabbit ears.
You especially notice the compression on gradients and in dark movie scenes.
And yes — my TV is fully calibrated, and I’m paying for the highest-bandwidth streaming tier.
Not my tv, but a visual example: https://www.reddit.com/media?url=https%3A%2F%2Fpreview.redd....
That can happen at even the highest bitrates if "HDR" is not enabled in the video codec.
Related video: https://www.youtube.com/watch?v=h9j89L8eQQk
At the higher prices, I'd have to agree with you. If you pay for the best you should get the best.
The biggest jump in quality was when everything was still analog over the air, but getting ready for the digital transition.
Then digital over the air bumped it up a notch.
You could really see this happen on a big CRT monitor with the "All-in-Wonder" television receiver PCI graphics adapter card.
You plugged in your outdoor antenna or indoor rabbit ears to the back of the PC, then tuned in the channels using software.
These were made by ATI before being acquired by AMD, the TV tuner was in a faraday cage right on the same PCB as the early GPU.
The raw analog signal was upscaled to your adapter's resolution setting before going to the CRT so you had pseudo better resolution than a good TV like a Trinitron. You really could see more details and the CRT was smooth as butter.
As the TV broadcaster's entire equipment chain was replaced, like camera lenses, digital sensors and signal processing they eventually had everything in place and working. You could notice these incremental upgrades until a complete digital chain was established as designed. It was really jaw-dropping. This was well in advance of the deadline for digital deployment, so the signal over-the-air was still coming in analog the same old way.
Eventually the broadcast signal switched to digital and the analog lights went out, plus the All-in-Wonder was not ideal with a cheap converter like analog TV's could get by with.
But it was still better than most digital TVs for a few years, then it took years more before you could see the ball in live sports as well as on a CRT anyway.
Now that's about all you've got for full digital resolution, live broadcasts from your local stations, especially live sports from a strong interference-free station over an antenna. You can switch between the antenna and cable and tell the difference when they're both not overly compressed.
The only thing was, digital engineers "forgot" that TV was based on radio (who knew?) so for the vast majority of "listeners" on the fringe reception areas who could get clear audio but usually not a clear picture if any, too bad for you. You're gonna need a bigger antenna, good enough to have gotten you a clear picture during the analog days. Otherwise your "clean" digital audio may silently appear on the screen as video, "hidden" within the sparse blocks of scattered random digital noise. When anything does appear at all.
Kate - Netflix - 11.15 Mbps
Andor - Disney - 15.03 Mbps
Jack Ryan - Amazon - 15.02 Mbps
The Last of Us - Max - 19.96 Mbps
For All Mankind - Apple - 25.12 Mbps
https://hd-report.com/streaming-bitrates-of-popular-movies-s...
Isn't AVI a container format and not a codec?