I don't have b-frames in the stream, and anyway, since I do the decoding myself, and not through the libav, I want it to leave the logic to me and just pass everything as it arrives. Is there anyway to cause it to work that way?
Carmel 2011/7/25 Alex Cohn <[email protected]> > On Monday, July 25, 2011, כרמל מגן <[email protected]> wrote: > > I have investigated the matter some more, and it seems that the delay is > exatcly 2 frames (its 80 ms when I use PAL 25 fps video and 66 ms when I > use NTSC 30 fps video). Furthermore, it appears when sending frames 1,2,3 > av_read_frame does not return with frame 1 before I start sending frame 3. > Does anybody have an idea why this might happen and how I can prevent it? > > Thanks > > Carmel > > The stream has a setting of max b-frames. If you can control your source, > simply set th his parameter to 0. Otherwise, you can work around the delay > produced by libav, but when the b-frame actually arrives, you will have to > wait, anyway. The behavior of libav is tuned to provide smooth playback with > constant delay. > > Regards, > Alex > > > > 2011/7/19 כרמל מגן <[email protected]> > >> > >> Hello > >> I have been integrating mpeg2 transport stream support into an > application I'm developing using libavformat. > >> After successfully transmitting my video (h.264 frames encoded by the > calling application) and receiving it, I did some latency testing. > >> To my surprise, I calculated 80 ms between the time that I finished > sending the frame in one process (av_write_frame returns) until I finish > receiving it in the second process (av_read_frame returns and the packet > contains the same frame). > >> To identify the frame I used the pts field of the packet. (i.e I printed > the time when sending together with the pts of the frame, and then the time > of receiving together with the pts of the frame, and then calculated the > difference). > >> This was tested using multicast transmission between 2 processes on the > same computer (on two different machines sitting on different networks) so I > don't believe network latency can account for it. > >> Can anybody explain what might be taking all that time and how I can > reduce it? My application demands very low latency. > >> Thanks > >> Carmel > > _______________________________________________ > Libav-user mailing list > [email protected] > http://ffmpeg.org/mailman/listinfo/libav-user > >
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