[gst-devel] bitrate in ffenc_h263p (and other encoders) not working

[Jared Moore]

Hi guys, I have a question about some encoders.

I am doing a project which involves sending video over RTP, simulating
a low-bandwidth connection and then manually fiddling around with the
encoder bitrate in order to compensate for the low bandwidth. My
question is that changing the bitrate on both the theoraenc and
ffenc_h263p elements doesn't seen to do anything.

Here is my code which i am using for testing:

gst-launch -v filesrc location=\"$1\" ! decodebin ! queue ! videorate
! ffmpegcolorspace ! ffenc_h263p bitrate=300 ! ffdec_h263 !
xvimagesink

This is just meant to test what different bitrates look like, and
testing whether bitrate actually works. This definitely works for h264
- setting the bitrate very low (e.g. 3) does make the video look
really horrible and use less bandwidth. Unfortunately I can only
really use h263 because other encodings that I've tried can't be done
in real-time on my eeepc. Changing the bitrate in the above code
snippet doesn't do anything visible, there's absolutely no change
between bitrate=1 and bitrate=300000.

Any thoughts or examples of how to use bitrate differently?

Alternatively, is there a way to substantially increase the
performance of the h264 encoder (with some other tradeoff, e.g. more
bandwidth required, having to make a new file, whatever, the only
problem is CPU usage)?

Cheers,
Jared