AVC and postprocessing

[madoka]

From my few trials with AVC (using x264 CLI) I'm convinced that it's superior to ASP (Xvid). Nevertheless, I still prefer postprocessed ASP to AVC. IMHO while AVC preserves more detail, it also tends to exhibit blocking. Non-postprocessed ASP obviously is even worse (with mosquito noise to boot), but with postprocessing most artifacts smooth out.

Unfortunately, existing postprocessing filters work poorly on AVC, I presume because they are tuned for ASP. Now is the lack of postprocessing filters for AVC due to its infancy, or is it inherent to the codec (since AVC has in-loop deblocking)?

I'm hoping it's the former, since changing in-loop deblocking setting would require a re-encode. At 5 fps, it's not fun...:(

[bond]

which avc codec did you use and what loop setting did you use?

[madoka]

which avc codec did you use and what loop setting did you use?
x264 revision 26x and upwards, and I left the in-loop deblocking at default. Most of my test encodes are < 1000 kbps.

[stephanV]

Unfortunately, existing postprocessing filters work poorly on AVC, I presume because they are tuned for ASP. Now is the lack of postprocessing filters for AVC due to its infancy, or is it inherent to the codec (since AVC has in-loop deblocking)?
Its inherent to the standard i think. I have never tried this, but maybe post-processing will work if you turn off deblocking all together. But there is a reasonable chance it will look just as shitty.

[bond]

hm 1000kbps is pretty high, strange that you get blocking. still if you want to reencode you can use high loopfilter settings, like 5,5

[rawr]

5,5 is way too high... I've found most blocking problem with h264 come from the source being noisy/generally bad, so the codec starts making a lot of wrong decisions over what blocks are equivalent temporally. If this *is* true in your case, I'd suggest adding some prefiltering to try and make the frames you pass more codec friendly.

rawr.

[Valeron]

5,5 is way too high... I've found most blocking problem with h264 come from the source being noisy/generally bad, so the codec starts making a lot of wrong decisions over what blocks are equivalent temporally. If this *is* true in your case, I'd suggest adding some prefiltering to try and make the frames you pass more codec friendly.

rawr.

Does it mean H.264 is not a good codec to maintain original picture?

[bond]

Does it mean H.264 is not a good codec to maintain original picture?
no :)

[Valeron]

How to manage AVC to keep more original details?
Or I should go higher bitrate?

[bond]

if you have enough storage space than you can higher the bitrate

but the x264 default values should also already provide great quality at 1cdr bitrates, enabling more goodies will help more of course

[rawr]

How to manage AVC to keep more original details?
Or I should go higher bitrate?
You appear to be confusing detail and noise. If you're doing a dvd backup at ~1/8th the bitrate, you get better quality by removing as much of the noise as possible - random doesn't compress. What I was saying is that whereas popular ASP codecs will flatten and smear when given noisy frames, I've noticed x264 can go flickery macroblock crazy. This isn't the fault of the codec as such, it's not trying to be a one-click solution like nero, it just means you need to be sensible about what you expect it to compress. How to best remove noise and gunk without destroying details... well, that's another issue.

rawr.

[bond]

rawr, do you have any screenshots showing this?

[Gannjunior]

Madoka,
why don't u use nero decoder? (have you used last ffdshow?)
imho, nero decoder, actually, is the best way to play an avc video.

ciao! :)

[bond]

Madoka,
why don't u use nero decoder? (have you used last ffdshow?)
imho, nero decoder, actually, is the best way to play an avc video
nero will not show less blocks than ffdshow of course...

[rawr]

rawr, do you have any screenshots showing this?Screenshots showing flickering blocks? No. Just add a lot of noise to any source you have to hand (preferably with some dark areas) then try and encode it. It's really not a codec issue, it just handles a paticular bad case in a less visually acceptable way than people are used to ASP codecs doing. And may not even be the exact problem that madoka was having at the start of this thread, was just a suggestion. At any rate, I doubt raising the inloop deblocking above sensible values will help more than harm.
nero will not show less blocks than ffdshow of course...
Indeed not. In fact, I think I remember peng. saying that any compliant h264 decoder should output bitwise identical frames.

rawr.

[Gannjunior]

nero will not show less blocks than ffdshow of course...
i don't know..when i reproduce by ffdshow, the avc video results ''dirtier" than the same video reproduced by nero decoder...btw i think she could have an attempt.. ;)

ciao!

[madoka]

Madoka,
why don't u use nero decoder? (have you used last ffdshow?)
imho, nero decoder, actually, is the best way to play an avc video.

ciao! :)
Well, because I'm cheap and don't want to spend the money to buy it :) I'm still using Nero 5 for all my disc burning needs. If the decoder is available by itself for free, I'm all ears...

Though, considering Nero 6 is a lot more than a disc burning software, it's really not that expensive overall.

And may not even be the exact problem that madoka was having at the start of this thread, was just a suggestion.
Well, not quite. ASP (XviD) without postprocessing blocks like hell too, but in addition whatever detail is obscured by the mosquito noise. Hence, the smoothed output postprocessing induces is better (at least that's my preference). AVC (x264) just blocks.

Of course, this is all based entirely on my subjective opinion. Maybe I'm just less used to the AVC-style artifacts, so I mistook them for actual details.

[bond]

i don't know..when i reproduce by ffdshow, the avc video results ''dirtier" than the same video reproduced by nero decoder...btw i think she could have an attempt.. ;)
placebo effect?
afaik the nero decoder does no postprocessing on avc as ffdshow does no postprocessing, so they output exactly the same picture