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AV2 video codec delivers 30% lower bitrate than AV1, final spec due in late 2025

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Re: AV2 video codec delivers 30% lower bitrate than AV1, final spec due in late 2025

#151

Post by axiolite »

mckirk wrote: post #54
lxgr wrote: post #31

Earlier quoted context omitted.

Yet I still only got hardware support for it on my first devices last year. The downside of "rapid" iteration on video codecs is that content needs to always be stored in multiple formats (or alternatively battery life on the client suffers from software playback, which is the route e.g. Youtube seems to be preferring).

It'd be really cool if we had 'upgradable codec FPGAs' in our machines that you could just use flash to the newest codec... but that'd probably be noticeably more expensive, and also not really in the interest of the manufacturers, who want to have reasons to sell new chips.

> FPGAs' in our machines that you could just use flash to the newest codec

They're called GPUs... They're ASICs rather than FPGAs, but it's easy to update the driver software to handle new video codecs. The difficulty is motivating GPU manufacturers to do so... They'd rather sell you a new one with newer codec support as a feature.

Re: AV2 video codec delivers 30% lower bitrate than AV1, final spec due in late 2025

#152

Post by adgjlsfhk1 »

pkulak wrote: post #127
alberth wrote: post #50

Will streaming services ever stop over-compressing their content? 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…

Are you sure about the black-areas-blocking? I remember a long time ago, when I was younger and had time for this kind of tomfoolery, I noticed this exact issue in my BlueRay backups. I figured I needed to up the bitrate, so I started testing, upping the bitrate over and over. Finally, I played the BlueRay and it was still there. This was an old-school, dual-layer, 100GB disc of one of the Harry Potter movies. Still…

the downside of 8 bits per channel is you really don't have enough to get a smooth gradient over dark colors.

Re: AV2 video codec delivers 30% lower bitrate than AV1, final spec due in late 2025

#153

Post by adgjlsfhk1 »

axiolite wrote: post #149
andsoitis wrote: post #112

Earlier quoted context omitted.

> Honestly, the best picture quality I’ve ever seen was over 20 years ago using simple digital rabbit ears. That I find super hard to believe!

Why? ATSC is 19Mbps. A single 1080i video using that whole bitrate will look quite good.

that's 19mbps including error correction. only 10 after, and that's using mpeg2 which is probably roughly equivalent to 6-7mbps av1

Re: AV2 video codec delivers 30% lower bitrate than AV1, final spec due in late 2025

#154

Post by dataflow »

ZeroGravitas wrote: post #141
benjiro wrote: post #131

Earlier quoted context omitted.

> randomized grains appear smoother to the human eye than clean uniform pixels Does this explain why i dislike 4K content on a 4K TV? Where some series and movies look too realistic, what in turn gives me a amateur film feeling (like somebody made a movie with a smartphone).

This sounds like what is called the soap opera effect: https://en.wikipedia.org/wiki/Soap_opera_effect Which is generally associated with excess denoisong rather than with excess grain.

Are you sure? That seems to be about motion interpolation. Not even about smooth motion, but about it being interpolated. Here the concern seems to be about how the individual, still images look, not anything about the motion between them.

Re: AV2 video codec delivers 30% lower bitrate than AV1, final spec due in late 2025

#155

Post by weaksauce »

benjiro wrote: post #131
trenchpilgrim wrote: post #117

Earlier quoted context omitted.

> camera manufacturers and film crews both do their best to produce a noise-free image This is not correct, camera manufacturers and filmakers engineer _aesthetically pleasing_ noise (randomized grains appear smoother to the human eye than clean uniform pixels). The rest is still as silly as it sounds.

> randomized grains appear smoother to the human eye than clean uniform pixels Does this explain why i dislike 4K content on a 4K TV? Where some series and movies look too realistic, what in turn gives me a amateur film feeling (like somebody made a movie with a smartphone).

i think i've seen this effect on tv shot on cameras that were lower fps than the tv outputs. looks fake and bad and interpolated because it is.

Re: AV2 video codec delivers 30% lower bitrate than AV1, final spec due in late 2025

#156

Post by axiolite »

adgjlsfhk1 wrote: post #153
axiolite wrote: post #149

Earlier quoted context omitted.

Why? ATSC is 19Mbps. A single 1080i video using that whole bitrate will look quite good.

that's 19mbps including error correction. only 10 after, and that's using mpeg2 which is probably roughly equivalent to 6-7mbps av1

"A terrestrial (over-the-air) transmission carries 19.39 megabits of data per second (a fluctuating bandwidth of about 18.3 Mbit/s left after overhead such as error correction, program guide, closed captioning, etc.),"

https://en.wikipedia.org/wiki/ATSC_standards#MPEG-2

Re: AV2 video codec delivers 30% lower bitrate than AV1, final spec due in late 2025

#157

Post by ZeroGravitas »

dataflow wrote: post #154
ZeroGravitas wrote: post #141

Earlier quoted context omitted.

This sounds like what is called the soap opera effect: https://en.wikipedia.org/wiki/Soap_opera_effect Which is generally associated with excess denoisong rather than with excess grain.

Are you sure? That seems to be about motion interpolation . Not even about smooth motion, but about it being interpolated . Here the concern seems to be about how the individual, still images look, not anything about the motion between them.

> some series and movies look too realistic, what in turn gives me a amateur film feeling

This comment that I replied to is almost a textbook description of the soap opera effect.

The interpolation adds more FPS, which is traditionally a marker of film vs TV production.

Re: AV2 video codec delivers 30% lower bitrate than AV1, final spec due in late 2025

#159

Post by strogonoff »

franga2000 wrote: post #114
strogonoff wrote: post #99

Earlier quoted context omitted.

Content delivery costs a lot for streaming services. After content is produced, this is basically the only remaining cost. It’s not surprising that they would go to extreme measures in reducing bitrate. That’s why, presumably, Netflix came up with the algorithm for removing camera grain and adding synthetically generated noise on the client[0], and why YouTube shorts were recently in the news for using extreme denois…

So: 1. camera manufacturers and film crews both do their best to produce a noise-free image 2. in post-production, they add fake noise to the image so it looks more "cinematic" 3. to compress better, streaming services try to remove the noise 4. to hide the insane compression and make it look even slightly natural, the decoder/player adds the noise back Anyone else finding this a bit...insane?

> 1. camera manufacturers and film crews both do their best to produce a noise-free image 2. in post-production, they add fake noise to the image so it looks more "cinematic"

This is patently wrong. The rest builds up on this false premise.

Re: AV2 video codec delivers 30% lower bitrate than AV1, final spec due in late 2025

#160

Post by simongr3dal »

toofy wrote: post #100
amiga386 wrote: post #80

Earlier quoted context omitted.

> but you aren't meant to really be able to see those colors Someone needs to tell filmmakers. They shoot dark scenes because they can - https://www.youtube.com/watch?v=Qehsk_-Bjq4 - and it ends up looking like shit after compression that assumes normal lighting levels.

> Someone needs to tell filmmakers. They shoot dark scenes because they can… i disagree completely. i watch a movie for the filmmakers story, i don’t watch movies to marvel at compression algorithms. it would be ridiculous to watch movies shot with only bright scenes because streaming service accountants won’t stop abusing compression to save some pennies. > …ends up looking like shit after compression that assumes n…

I feel like there are probably cinematic film-making tricks you can use to imply a very dark scene without serving #111 pixels all over the screen.
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