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

[Karim SLIMANI]

hello,

i think you need to increase fifo_size parameter. (remove pkt_size and
buffer_size parameters, but keep overrun_nonfatal=1)

try a fifo_size=524288 if it continue to crash, then try a value of
fifo_size=2621400

Circular buffer overrun happen when the computer cannot catch up in
processing received data, so increasing the size may help (ie: fifo_size)
To understand what is happening here, take a look at
https://github.com/FFmpeg/FFmpeg/blob/master/libavformat/udp.c#L500

Best regards,


Le mar. 27 oct. 2020 à 22:19, Daniel Dimitrov <596076 at gmail.com> a écrit :

> 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!
> _______________________________________________
> ffmpeg-user mailing list
> ffmpeg-user at ffmpeg.org
> https://ffmpeg.org/mailman/listinfo/ffmpeg-user
>
> To unsubscribe, visit link above, or email
> ffmpeg-user-request at ffmpeg.org with subject "unsubscribe".