[FFmpeg-devel] modify ffplay for dumpstream in rtsp?
ffmpeg at panteltje.com
Sat Oct 3 10:32:00 CEST 2015
// ffmpeg-devel at ffmpeg.org
I was experimenting with using ffplay to display cameras from my DVR video recorder'srtsp stream.
This works perfectly (Chinse video recoder with H264 outoput for4 cameras) like this:
As I found no way to record from it at the same time?? (maybe ffmpeg can but no luck so far),
I decided to try to add some output stream to fflay.
I modified ffplay.c
static int video_thread(void *arg)
ret = get_video_frame(is, frame, &pts_int, &pkt, &serial);
if (ret < 0)
/* Start PANTELTJE MOD */
//fprintf(stderr, "WAS 1 pkt.size=%d\n", pkt.size);
// ssize_t write(int fd, const void *buf, size_t count);
write(fileno(stdout), pkt.data, pkt.size);
/* end PANTELTJE MOD */
Recompiled, then use it like this:
ffplay 'rtsp://192.168.178.80:554/user=admin_password=PASSWORD_channel=1_stream=0.sdp?real_stream?tcp' 1>myfile.mp4
Amazingly this worked first time, and I can play it back no problem with an unmodified version of ffplay :-)
There is _one_ problem however, the recorded file plays back at what looks like double speed.
I was thinking about adding a command line option to ffplay to enable the 'dump to stdout' modification,
but am taken aback by why I do not understand the double speed effect in playback.
I know very little about H264 sooo
What is going on here?
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