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Re: Ultimate Profile?

Posted: Mon Jan 18, 2010 4:43 am
by creamyhorror
please_help wrote: Thanks for getting involved creamyhorror and thanks for sharing your preferences. I wasn’t sure whether the hit in speed by increasing bframes was actually worth it for general use? After looking at my logs it seems like 3 consecutive bframes are used fairly rarely, generally less than 10% of the time for the random selection of movies I tested and pretty close to the percentage of time that none are used at all.
Most movies for me are in the 4-5 bframe range. If they're used even 3 or even 2% of the time, I let x264 go ahead. Don't know whether it's worth the time hit to you, though.
With regards to deblocking, I read that deblocking decreases with higher bit rate so if one were to go for crf 18 then deblocking at 0,0 would be similar to deblocking -1,-1 (or something) at crf 20? I guess this is down to personal taste, but I’d rather not risk any blocking artifacts and if I stick to my reason for starting this topic and assume that the HB developers got it right, I would (tentatively) suggest 0,0 for a general use higher-than-high profile?
Blocking artifacts are minimal even at -3,-3. You have to understand that blocking is an inherent result of x264's encoding process, and the deblocker acts to soften the blocks - but in the process necessarily blurs out a bit of detail. For complex or grainy sources, it's better to keep deblocking low so that less detail will be blurred out. I doubt anyone notices the blocks; I have to pause, zoom and look pretty hard to make them out. In normal viewing, they simply look like part of the detail (IMO).

Re: Ultimate Profile?

Posted: Mon Jan 18, 2010 5:14 am
by please_help
Cheers mate. Thanks for the info.

Regarding bframes; I guess I’d need to do lots more testing to find a better answer but maybe it’s worth trusting the x264 developers decision (for the purposes of this topic) that they have only increased bframes in the placebo preset, although they have gone crazy and selected 16?

I’m not sure what the answer is regarding deblocking. Sharktooth seems to go for -1,-1 as standard but x264 developers have set 0,0 to work for most sources and it seems like HandBrake developers have agreed? But it’s good to know that even at -3,-3 it’s very hard to see any blocking.

Off topic; what I’d like to have is a very high granularity of speed steps so you could adjust x264 presets very accurately for your own desired encoding speed. So for example; 100 steps between ultrafast and placebo (but I completely understand why they haven’t done this).

Re: Ultimate Profile?

Posted: Mon Jan 18, 2010 7:56 am
by please_help
Seeing as there appears to be a distinct lack of interest in this thread and apparent pointlessness in continuing it for the benefit of other HandBrake users. I shall now leave this forum never to return (there was much rejoicing).

At least the situation between creamyhorror and myself was appeased via PM and Statick found this topic somewhat useful.

So long, and thanks for all the fish.