Quote:
Originally Posted by h3nry
yeah but h.264 rearly uses bframes >3.when setting adaptive bframes=optimal,setting more than 4/5 bframe is insane unless you have lot of time to waste.
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I just tried a quick little test encode to experiment. Using a 4 minute 704x384 AVI as the source. I used presetveryslow and tuning=grain. Maximum consecutive bframes was 7, but the instance of more than 3 consecutive bframes only totalled 2.5% of the b frames used. Limiting the number of bframes to 5 shaved 3 seconds of encoding time, bframes 3 shaved off another 7, so no doubt it makes some difference.
In terms of speed decrease I don't think it falls into the "insane" department though. At least not in terms of having a lot of time to waste when compared to some of the settings you prefer.
VerySlow and tuning grain are as close to your settings as I could get using the standard x264 presets. The same encode using x264's default settings reduced the encoding time by 3 min, 20 seconds.
I think you're wrong about level 3.2 needing a limit of 13 ref frames. The way I read it on Wikipedia it only applies to level 3.1 and it's probably when using a 720x? resolution too. When setting 3.1 as the level x264 didn't limit my 704x384 encode to 13 ref frames. To make sure it was working correctly I tried again at 720p and sure enough it limited ref frames to 5 even though the preset says 16.