Record RTSP stream with FFmpeg libavformat

Question

I\'m trying to record RTSP stream from Axis camera with FFmpeg libavformat. I can grab video from files and then save it to another file, this is OK. But camera sends strang

Answer 1

Recently was doing the same. I had FPS twice lower than the camera sent. The reason was in AVstream->codec->ticks_per_frame field, set to 2. My source was progressive, and in case yours in interleaved - then that might be a reason of yet another factor of 2, giving 4x different FPS. 90000 Hz is the default timebase for video stream sent via RTSP. Timebase is different from FPS in resolution. For instance, a frame with timestamp 30000 will be shown at 1/3 sec if the timebase is 90000 Hz. The timebase should be put into the AVstream structure during the output, but AVFormatContext should have a real FPS value.