[FFmpeg-user] Need help to re-stream multicast

Daniel Dimitrov 596076 at gmail.com
Tue Oct 27 23:19:10 EET 2020


Dear all,
I try to retransmit  multicast stream . I can partially manage to do it
unfortunately some interruptions in the stream appear , Please help me to
correctly calculate the parameters for the udp url (fifo_size ,
buffer_size,bitrate, pkt_size) i want to set video bitrate to 3M and i am
not sure if i have to do muxrate. Command is here :

*ffmpeg -i
"udp://@238.252.250.9:5000?overrun_nonfatal=1&fifo_size=350000&pkt_size=1316&buffer_size=10000000
<http://238.252.250.9:5000?overrun_nonfatal=1&fifo_size=350000&pkt_size=1316&buffer_size=10000000>"
   -vf scale=720:576    -b:v 3M -maxrate 4M -bufsize 8M   -b:a 128k
 -muxrate 5M -f mpegts
"udp://@239.253.251.13:5505?overrun_nonfatal=1&fifo_size=350000&pkt_size=188&&buffer_size=2000000&bitrate=5000000
<http://239.253.251.13:5505?overrun_nonfatal=1&fifo_size=350000&pkt_size=188&&buffer_size=2000000&bitrate=5000000>"*

i have doubts about most of the udp parameters so please correct me if
anything looks wrong to you.

*Here is the input stream:*

Input #0, mpegts, from 'udp://@238.252.250.9:5000':
  Duration: N/A, start: 31142.994278, bitrate: N/A
  Program 2002
    Metadata:
      service_name    : RT Doc HD
      service_provider: GLOBECAST
    Stream #0:0[0x7e5]: Video: h264 (High) ([27][0][0][0] / 0x001B),
yuv420p(tv, bt709, top first), 1920x1080 [SAR 1:1 DAR 16:9], 25 fps, 50
tbr, 90k tbn, 50 tbc
    Stream #0:1[0x7e6](eng): Audio: ac3 (AC-3 / 0x332D4341), 48000 Hz,
stereo, fltp, 192 kb/s
    Stream #0:2[0x7e7](eng): Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz,
stereo, fltp, 192 kb/s


* If i execute the command above it crashes after 5min with :*


[h264 @ 0x6b52480] reference picture missing during reorder
    Last message repeated 1 times
[h264 @ 0x6b52480] Missing reference picture, default is 65814
    Last message repeated 1 times
[h264 @ 0x6ad5380] reference picture missing during reorder
[h264 @ 0x6ad5380] Missing reference picture, default is 65815
Output #0, mpegts, to 'udp://@
239.253.251.13:5505?overrun_nonfatal=1&fifo_size=350000&pkt_size=188&&buffer_size=2000000&bitrate=4000000
':
  Metadata:
    encoder         : Lavf58.45.100
    Stream #0:0: Video: mpeg2video (Main), yuv420p, 720x576 [SAR 64:45 DAR
16:9], q=2-31, 3000 kb/s, 25 fps, 90k tbn, 25 tbc
    Metadata:
      encoder         : Lavc58.91.100 mpeg2video
    Side data:
      cpb: bitrate max/min/avg: 4000000/0/3000000 buffer size: 2000000
vbv_delay: N/A
    Stream #0:1(eng): Audio: mp2, 48000 Hz, stereo, s16, 128 kb/s
    Metadata:
      encoder         : Lavc58.91.100 mp2
    Stream #0:2(eng): Audio: mp2, 48000 Hz, stereo, s16, 128 kb/s
    Metadata:
      encoder         : Lavc58.91.100 mp2
av_interleaved_write_frame(): Cannot allocate memory:18.08
bitrate=4995.0kbits/s speed=1.01x
    Last message repeated 1 times
Error writing trailer of udp://@
239.253.251.13:5505?overrun_nonfatal=1&fifo_size=350000&pkt_size=188&&buffer_size=2000000&bitrate=4000000:
Cannot allocate memory
frame= 9427 fps= 25 q=2.8 Lsize=  230612kB time=00:06:18.24
bitrate=4994.6kbits/s speed=1.01x
video:138661kB audio:11807kB subtitle:0kB other streams:0kB global
headers:0kB muxing overhead: 53.263130%
[udp @ 0x682e200] Circular buffer overrun. Surviving due to
overrun_nonfatal option
    Last message repeated 121516 times
Conversion failed!


More information about the ffmpeg-user mailing list