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Old 9th November 2010, 22:47   #1  |  Link
Tuik
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Max B-frames

What is the maximum reasonable value for max b-frames? In x264 it's possible to use 16 consecutive b-frames.. and in xvid? And would be it useful? Thanks a lot
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Old 10th November 2010, 05:09   #2  |  Link
Sharktooth
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4 for xvid, 16 for x264. remember the more is not always the better.
always use the adaptive b-frames option coz the encoder will choose when to place b-frames and when not.
x264 in that regard has a more effective/complex algo for b-frames placement (when b-adapt 2 is set) while xvid relies on a simpler one.

Last edited by Sharktooth; 10th November 2010 at 05:23.
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Old 10th November 2010, 07:01   #3  |  Link
Dark Shikari
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Quote:
Originally Posted by Sharktooth View Post
4 for xvid, 16 for x264
No, 16 is not a "reasonable value"... the defaults are reasonable values...
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Old 10th November 2010, 08:19   #4  |  Link
zmaster
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A very popular question.
3 b-frames for the x264 and 1 for Xvid (For best compatibility with standalone Players).
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Old 10th November 2010, 09:08   #5  |  Link
burfadel
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3 for compatibility with standalone players, 5 (seems to be a fairly typical maximum effective number) with --b-adapt 2.
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Old 10th November 2010, 17:35   #6  |  Link
Sharktooth
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i missed the "reasonable" word... i just told him the maxium...
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Old 10th November 2010, 18:42   #7  |  Link
SeeMoreDigital
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Quote:
Originally Posted by zmaster View Post
... 1 for Xvid (For best compatibility with standalone Players).
Indeed, for cheap stand-alones with low-spec decoding chip-sets and firmware.

Something else to bear in mind... Given that early DivX encoders only offered the capability of generating MPEG-4.2 ASP encodes with "one" B-frame (together with packed bit-stream), there was very little incentive for manufacturers of "DivX certified" stand-alone players to support more than one B-frame!


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