Good day to all. I'm using libav in my application to encode live video to h264, mux it in Live Smooth Streaming format and send to IIS Live Smooth Streaming publishing point (via http).
I need to achieve quite low latency (<3 seconds) of live video. When the video is recorded on regular frame rate (20-30 fps), everything is good and latency is even lower. But when I try lower fps values, the latency grows. For 5 fps the latency is 5-6 seconds, for 2 fps it is 11 seconds and for 1 fps - 21 second. I've measured time of the encoding of each frame, it is approximately 1.5 seconds and didn't changed with fps. Also disabled all buffering at the video player side to exclude it. So the problem seems to be somewhere at http transfer process (that is performed by libav too). First I thought that some kind of buffer is used in libav for http transfer, and on the lower frame rate it is filled slower, and that's the reason of increased latency. But changing video resolution and bitrate doesn't affect on latency, though obviously should change encoded frame size and so change the buffer filling rate. Now I'm completely out of ideas what is reason of that latency and how to remove it. Does anyone have any suggestions? Thanks in advance, Aleksey _______________________________________________ Libav-user mailing list Libav-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/libav-user