[Libav-user] video bitrate control far from accuracy

Carl Eugen Hoyos cehoyos at ag.or.at
Thu Jul 17 11:31:23 CEST 2014

谭艳梅 <tanyanmei at ...> writes:

> I'm transcoding with ffmpeg API .  but the video frame 
> rate of  the target file is far from accuracy .

(The frame rate or the bit rate?)

Is this reproducible with ffmpeg (the application)?

To test if it is at all possible to reach a given bitrate 
for a given input file, you can use a high constant 
quantizer to test:
$ ffmpeg -i input -qscale 31 -vcodec h263 out.avi

I don't think 22k for qcif and h263 is realistic.

If you really meant frame rate than you can choose it 
freely assuming the container allows it.

Carl Eugen

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