[FFmpeg-user] Howto specify needed options for ffmpeg

[Thomas Seilund]

Dear All

I don't know how to read a h264 network stream with ffmpeg.


I create the stream on a Raspberry Pi with this command:

raspivid -t 0 -b 10000000 -n -o test.h264


I am able to view the video with ffplay:

ffplay -i test.h264 
ffplay version N-97152-g52523b6963 Copyright (c) 2003-2020 the FFmpeg
developers built with gcc 8 (Raspbian 8.3.0-6+rpi1)
  configuration: --extra-libs='-lpthread -lm' --enable-gpl
--enable-libass --enable-libfreetype --enable-libmp3lame
--enable-libvorbis --enable-libx264 --disable-doc --enable-nonfree
libavutil      56. 42.102 / 56. 42.102 libavcodec     58. 77.101 / 58.
77.101 libavformat    58. 42.100 / 58. 42.100 libavdevice    58.
9.103 / 58.  9.103 libavfilter     7. 77.101 /  7. 77.101
  libswscale      5.  6.101 /  5.  6.101
  libswresample   3.  6.100 /  3.  6.100
  libpostproc    55.  6.100 / 55.  6.100
Input #0, h264, from 'test.h264':  0KB vq=    0KB sq=    0B f=0/0   
  Duration: N/A, bitrate: N/A
    Stream #0:0: Video: h264 (High), yuv420p(progressive), 1920x1080,
25 fps, 25 tbr, 1200k tbn, 50 tbc Switch subtitle stream from #-1 to
#-1 vq=   55KB sq=    0B f=0/0 nan M-V:    nan fd=   2 aq=    0KB vq=
54KB sq=    0B f=0/0   


Now I write to udp and not to a local file with this command:

raspivid -t 0 -b 10000000 -n -o udp://239.255.42.42:5004
Connecting to 239.255.42.42:5004...connected, sending video...


On the same host I read from udp with this command - video is never
displayed

ffplay -f h264 -i udp://239.255.42.42:5004
ffplay version N-97152-g52523b6963 Copyright (c) 2003-2020 the FFmpeg
developers built with gcc 8 (Raspbian 8.3.0-6+rpi1)
  configuration: --extra-libs='-lpthread -lm' --enable-gpl
--enable-libass --enable-libfreetype --enable-libmp3lame
--enable-libvorbis --enable-libx264 --disable-doc --enable-nonfree
libavutil      56. 42.102 / 56. 42.102 libavcodec     58. 77.101 / 58.
77.101 libavformat    58. 42.100 / 58. 42.100 libavdevice    58.
9.103 / 58.  9.103 libavfilter     7. 77.101 /  7. 77.101
  libswscale      5.  6.101 /  5.  6.101
  libswresample   3.  6.100 /  3.  6.100
  libpostproc    55.  6.100 / 55.  6.100
[udp @ 0xae600dd0] attempted to set receive buffer to size 393216 but
it only ended up set as 327680 [h264 @ 0xae611a80] non-existing PPS 0
referenced sq=    0B f=0/0 Last message repeated 1 times
[h264 @ 0xae611a80] decode_slice_header error
[h264 @ 0xae611a80] no frame!
[h264 @ 0xae611a80] non-existing PPS 0 referenced
    Last message repeated 2 times
[h264 @ 0xae611a80] decode_slice_header error
[h264 @ 0xae611a80] no frame!
[h264 @ 0xae611a80] non-existing PPS 0 referenced
[h264 @ 0xae611a80] decode_slice_header error
[h264 @ 0xae611a80] no frame!
[h264 @ 0xae611a80] non-existing PPS 0 referenced
    Last message repeated 1 times
[h264 @ 0xae611a80] decode_slice_header error
[h264 @ 0xae611a80] no frame!
[h264 @ 0xae611a80] non-existing PPS 0 referenced sq=    0B f=0/0   
    Last message repeated 2 times
[h264 @ 0xae611a80] decode_slice_header error
[h264 @ 0xae611a80] no frame!o ffmpeg-user at ffmpeg.org.
[h264 @ 0xae611a80] non-existing PPS 0 referenced
[h264 @ 0xae611a80] decode_slice_header error
[h264 @ 0xae611a80] no frame!


If I probe the stream I get this:

ffprobe -f h264 -i udp://239.255.42.42:5004
.
.
.
[h264 @ 0x37fbe20] no frame!
[h264 @ 0x37fbe20] non-existing PPS 0 referenced
    Last message repeated 1 times
[h264 @ 0x37ea9d0] decoding for stream 0 failed
[h264 @ 0x37ea9d0] Could not find codec parameters for stream 0 (Video:
h264, none): unspecified size Consider increasing the value for the
'analyzeduration' and 'probesize' options Input #0, h264, from
'udp://239.255.42.42:5004': Duration: N/A, bitrate: N/A
    Stream #0:0: Video: h264, none, 25 fps, 25 tbr, 1200k tbn, 50 tbc
pi at raspberrypi:~/temp/camera $ 


It there any way I can specify all needed options for ffmpeg so
ffmpeg will be able to work with the stream? I don't know how to use
the analyzeduration and probesize options.

Thanks

Thomas S