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Old 4th June 2021, 20:34   #6  |  Link
benwaggoner
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Join Date: Jan 2006
Location: Portland, OR
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Quote:
Originally Posted by Mitra View Post
So, please explain the reference of the first two B-frames of this sample and show me how we can do this by x264 , Etc.

StreamEye says the only reference for both is the first IDR.

Note: I'm talking about the first 2 B-frames , not the rest of the stream.
OH! Gotcha. Sounds like RADL from x265. In that case, they are B-frames only in the sense that the allow prediction from frames later in temporal order.

I think it is technically possible for one of those to reference a P-frame after the IDR, but for most content the encoder wouldn't find useful references there to use, so they wouldn't be in the list.

x264 doesn't have --radl, of course. You could evaluate this if you used a QPfile to force a "bbIP" start sequence, and make the P a better reference for the bb than the I is.
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