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Old 31st May 2016, 18:56   #3  |  Link
Blue_MiSfit
Derek Prestegard IRL
 
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Join Date: Nov 2003
Location: Los Angeles
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Quote:
9- How can i encode at specific bitrate, for example 3mbs BUT without ANY vbr, i dot care if the compression jumps from q10 to q30 from one frame to another as long as it stays at 3mbs ALL THE TIME, constant bitrate, REALLY constant (it will look horrible, i know but i need it to test something)
AFAIK If you must have TRUE constant bitrate (almost never really needed), then you must use single frame VBV. You also have to enable filler. I don't know how to make x264 size each frame perfectly without any padding.

Assuming 30fps video, set --bitrate 3000 --vbv-maxrate 3000 --vbv-bufsize 100 --nal-hrd cbr --filler

Also, output an elementary stream.

Finally, in cases where you need to hit an exact bitrate all the time (like MPEG-TS for broadcast etc) it's typical to fill the mux with null packets, instead of padding at the ES level. Not sure if that's what you're trying to do, but yeah...
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