I create TPorocess for ffmpeg to stream a video from /dev/video0 in Linux Ububntu 14.04. After 5 minutes of work the stream send stops and on the receiveng side (ffplay) the picture freezes.
The strange thing - If I try to read stdout of ffmpeg with cat /procs/3535 (where 3535 is ffmpeg PID) it continues to work and the client sees the live picture again! After next 5 minutes of work this situation repeats. And thr call to read stdout helps again.
When I stream an audio stream the same way it doesn't happen. When I start ffmpeg video streaming from terminal it works without the problem!
OS Linux Ubuntu 14.04 32-bit. FFmpeg v3.4 built with GCC 4.8
FFmpeg start string:
ffmpeg -vsync drop -frame_drop_threshold 1 -f v4l2 -video_size 640x480 -i /dev/video0 -vcodec libx264 -pix_fmt yuv420p -tune zerolatency -preset ultrafast -b 500k -fflags +genpts -f rtp rtp://10.0.6.70:2666
Free Pascal code:
FVideoTranslation := TProcessUTF8.Create(nil);
FVideoTranslation.Options := [poUsePipes];
with FVideoTranslation do
begin
Executable := Format(PATH_PATTERN, [FProgramPath, TRANSLATION_PROGRAM]);
Parameters.Add('-vsync');
Parameters.Add('drop');
Parameters.Add('-frame_drop_threshold');
Parameters.Add('1');
DeviceParams := GetCaptureParam(AVideoDevice, dtVideo);
for i := 0 to DeviceParams.Count - 1 do
Parameters.Add(DeviceParams[i]);
FreeAndNil(DeviceParams);
Parameters.Add('-vcodec');
Parameters.Add('libx264');
Parameters.Add('-pix_fmt');
Parameters.Add('yuv420p');
Parameters.Add('-tune');
Parameters.Add('zerolatency');
Parameters.Add('-preset');
Parameters.Add('ultrafast');
Parameters.Add('-b');
Parameters.Add('500k');
Parameters.Add('-fflags');
Parameters.Add('+genpts');
Parameters.Add('-f');
Parameters.Add('rtp');
Parameters.Add('rtp://%s:%d', [AAbonentIp, AVideoPort]);
Execute();
Log.AddMessage(Parameters.Text);
end;
SdpInfo.Clear;
while (SdpInfo.Count = 0) do
try
SdpInfo.LoadFromStream(FVideoTranslation.Output);
except
on E: Exception do
Log.AddMessage('VideoTranslation.Output: ' + E.Message);
end;
Log.AddMessage(SdpInfo.Text);
FVideoFile := SdpInfo.Text;
Any suggestions why it can be?
