State of b-pyramid

[juGGaKNot]

Right now i use "--bframes 4 --b-adapt 2" with no b-pyramid for game footage and i'm thinking of b-pyramid

Is b-pyramid dxva/ps3/standalone players friendly today ?

Thinking of --bframes 4 --b-adapt 2 --b-pyramid

Is it safe for up to 1280x800 with 4 b-frames ?

Complete cmd line if needed

--level 4.0 --sar 1:1 --aud --nal-hrd --vbv-bufsize 24000 --vbv-maxrate 24000 --ref 4 --mixed-refs --bframes 4 --b-adapt 2 --weightb --direct auto --subme 9 --trellis 2 --psy-rd 1.0:0.4 --partitions all --8x8dct --me tesa --fullrange on --qcomp 1 --threads auto --thread-input --aq-mode 1 --aq-strength 0.4 --progress --no-psnr --no-ssim

THNX, cheers.

[Sharktooth]

b-pyramid still brakes the DPB in some cases.

[juGGaKNot]

b-pyramid still brakes the DPB in some cases.

Random cases or related to high b-frame count ?

Will 4 refs/4b-frames/b-pyramid brake even under 720p in some cases ?

[tetsuo55]

It depends on the target hardware and the number of ref frames used (and on some hardware, the number of b frames).

For a completely portable file, b-pyramids are not recommended, for a single target that has no problems with it i say go ahead and use it, it saves quite a bit on the compression side.

[Sharktooth]

that "quite a bit" is usually close to zero.

[juGGaKNot]

@tetsuo55 PS3/xbox is the target, maybe a tivo or other player also.

4 refs/4b 1280x800 about the maximum resolution used, most used is 1024x576 and lower.

that "quite a bit" is usually close to zero.
that why not remove it if there is no time to fix/does not help

Or label it as placebo or ..

[Sharktooth]

it's not a placebo. it works, and in some situations helps more than in others.
however it's partially broken and it doesnt work on some hardware.

[juGGaKNot]

it's not a placebo. it works, and in some situations helps more than in others.
however it's partially broken and it doesnt work on some hardware.

That "some" being ?

As said main goal is at least ps3/xbox compatibility + hardware players like tivo or others better known.

[nurbs]

I just encoded a short clip (720p) with 3 b-frames and for the encode with b-pyramide enabled the global psnr was 0.1 dB higher if it's numbers you are interested in. I can't really see a difference.

[LoRd_MuldeR]

I just encoded a short clip (720p) with 3 b-frames and for the encode with b-pyramide enabled the global psnr was 0.1 dB higher if it's numbers you are interested in. I can't really see a difference.

If this was measured with Psy-RD/Trellis enabled, the number doesn't say anything ;)

And if you can't see the difference, then probably the overall bitrate was simply too high...

[elguaxo]

or others better known.

The Western Digital TV HD Media Player (cheap and very popular I'd say) and the Popcorn Hour don't have problems with b-pyramid. And I think you can use 3 b-frames and b-pyramid on the PS3. Don't quote me on the PS3 settings, because I don't have one.

[juGGaKNot]

The Western Digital TV HD Media Player (cheap and very popular I'd say) and the Popcorn Hour don't have problems with b-pyramid. And I think you can use 3 b-frames and b-pyramid on the PS3. Don't quote me on the PS3 settings, because I don't have one.

THNX, i would like to use 4 and b-pyramid, any ps3 testers that have a conclusion ?

[nurbs]

@Lord Mulder:
Allright, without the psy stuff we are down to +0.08 on that clip.

@juggaknot:
Never had problems with b-pyramid on the ps3.

[Ghitulescu]

My Pioneer can play b-pyramids with refs of 3 maybe 4, as there are also other factors.

[tetsuo55]

IIRC the effect of b-pyramids is an "on average" 5% increase of compression without any measurable loss of image quality.

I also remember B-Pyramids causing problems on PS3 hardware in the past, but since it's all software based this could have been fixed in any of the many updates.

[juGGaKNot]

Never had problems with b-pyramid on the ps3.

My Pioneer can play b-pyramids with refs of 3 maybe 4, as there are also other factors.


K, i will use it with 4 b frames and test.

IIRC the effect of b-pyramids is an "on average" 5% increase of compression without any measurable loss of image quality.

I also remember B-Pyramids causing problems on PS3 hardware in the past, but since it's all software based this could have been fixed in any of the many updates.

Doesn't 5% mean better quality at same bitrate in 2 pass mode ?

[LoRd_MuldeR]

Doesn't 5% mean better quality at same bitrate in 2 pass mode ?

Yes. Either better quality at same bitrate -or- same quality at lower bitrate. But it does not necessarily mean 5% smaller file at same CRF ;)

Anyway, it depends on the overall bitrate and on the type of content how "visible" the difference will be. PSNR certainly is not a good measure for overall quality...

[juGGaKNot]

Yes. Either better quality at same bitrate -or- same quality at lower bitrate. But it does not necessarily mean 5% smaller file at same CRF ;)

Anyway, it depends on the overall bitrate and on the type of content how "visible" the difference will be. PSNR certainly is not a good measure for overall quality...

i do not use crf so it is k, i must test 4 b with pyramid on ps3 and we will see.

[Sharktooth]

IIRC the effect of b-pyramids is an "on average" 5% increase of compression without any measurable loss of image quality.

I also remember B-Pyramids causing problems on PS3 hardware in the past, but since it's all software based this could have been fixed in any of the many updates.
false. 5% is far from the real compression. less than 1% is more accurate in most situations.

[Audionut]

No problems here from memory with --b-pyramid and --bframes 5 with a resolution of 1280x544 on PS3.