Encode/Decode pair with Decklinks and FFMPEG

Has anyone ever setup a encode/decode pair using FFMPEG and Decklinks? (or any other software?). The end goal is to bring in a remote camera feed into the studio switcher so quality and low latency is important. There is a private ethernet network already setup between the two studios.

I'm testing using this on the encoder (10.40.0.100)

Code: Select all

ffmpeg -f decklink -video_input 'sdi' -i 'DeckLink SDI (1)' -f mpegts  udp://10.40.0.111:8090

and on the receiving computer (10.40.0.111) I'm just trying to playback using ffplay (eventually this will output to another decklink)

Code: Select all

ffplay -f mpegts udp://10.40.0.111:8090

but the playback is unstable and I get all these errors. I'm sure I have some settings wrong but no idea what.

Code: Select all

[mpeg2video @ 0x7a6fcc0c7500] Invalid mb type in I-frame at 0 30
[mpeg2video @ 0x7a6fcc0c7500] Warning MVs not available
[mpeg2video @ 0x7a6fcc0c7500] concealing 540 DC, 540 AC, 540 MV errors in I frame
[mpegts @ 0x7a6fcc000cc0] PES packet size mismatchsq=    0B f=0/0   
[mpegts @ 0x7a6fcc000cc0] Packet corrupt (stream = 1, dts = 7109221).
[mpeg2video @ 0x7a6fcc0c7500] ac-tex damaged at 20 19
[mpeg2video @ 0x7a6fcc0c7500] Warning MVs not available
[mpeg2video @ 0x7a6fcc0c7500] concealing 540 DC, 540 AC, 540 MV errors in P frame
[mpegts @ 0x7a6fcc000cc0] Packet corrupt (stream = 1, dts = 7113541).
[mpegts @ 0x7a6fcc000cc0] Packet corrupt (stream = 0, dts = 7116984).
[mpeg2video @ 0x7a6fcc0c7500] end mismatch left=1060 8893 at 0 31   
[mpeg2video @ 0x7a6fcc0c7500] Warning MVs not available
[mpeg2video @ 0x7a6fcc0c7500] concealing 0 DC, 0 AC, 0 MV errors in P frame
[mpegts @ 0x7a6fcc000cc0] Packet corrupt (stream = 1, dts = 7117861).
[mpegts @ 0x7a6fcc000cc0] Packet corrupt (stream = 1, dts = 7122181).
[mp2 @ 0x7a6fcc0c9680] Header missingB vq=  456KB sq=    0B f=0/0   
[mpeg2video @ 0x7a6fcc0c7500] end mismatch left=1124 9380 at 0 31
[mpeg2video @ 0x7a6fcc0c7500] Warning MVs not available
[mpeg2video @ 0x7a6fcc0c7500] concealing 0 DC, 0 AC, 0 MV errors in P frame
[mpegts @ 0x7a6fcc000cc0] Packet corrupt (stream = 1, dts = 7126501).
[mpegts @ 0x7a6fcc000cc0] Packet corrupt (stream = 1, dts = 7130821).
[mpeg2video @ 0x7a6fcc0c7500] end mismatch left=1060 8893 at 0 31   
[mpeg2video @ 0x7a6fcc0c7500] Warning MVs not available
[mpeg2video @ 0x7a6fcc0c7500] concealing 0 DC, 0 AC, 0 MV errors in P frame
[mpeg2video @ 0x7a6fcc0c7500] ac-tex damaged at 16 25    0B f=0/0   
[mpegts @ 0x7a6fcc000cc0] Packet corrupt (stream = 1, dts = 7139461).
[mpegts @ 0x7a6fcc000cc0] Packet corrupt (stream = 0, dts = 7144011).
[mpeg2video @ 0x7a6fcc0c7500] ac-tex damaged at 41 30
[mpeg2video @ 0x7a6fcc0c7500] Invalid mb type in I-frame at 0 20
[mpeg2video @ 0x7a6fcc0c7500] Warning MVs not available
[mpeg2video @ 0x7a6fcc0c7500] concealing 1260 DC, 1260 AC, 1260 MV errors in I frame
[mp2 @ 0x7a6fcc0c9680] Header missing
    Last message repeated 1 times
[mpegts @ 0x7a6fcc000cc0] Packet corrupt (stream = 1, dts = 7143781).
[mpegts @ 0x7a6fcc000cc0] Packet corrupt (stream = 0, dts = 7153020).


Any guidance would be appreciated.

U was not specified codec and video parameters

I ended up changing to...

Code: Select all

ffmpeg -f decklink -video_input 'sdi' -i 'DeckLink SDI (1)' -c:v libx264 -preset veryfast -tune zerolatency -bf 0 -c:a aac -f mpegts udp://10.40.0.111:8090

...with much better success. now I just need to find the right codec and parameters to work well with the actual remote connection.

x264 is top .. but veryfast is not verygood .. Its the lowest quality , but lower latency too ..

Any guidance on what the proper command would be on the decoder to playback this UDP stream on it's Decklink? I was able to successfully encode using:

Code: Select all

ffmpeg -f decklink -video_input 'sdi' -i 'DeckLink SDI (1)' -c:v libx264 -preset veryfast -tune zerolatency -bf 0 -c:a aac -f mpegts udp://192.168.100.10:8080

I'm able to playback on 192.168.100.10 using ffplay but ultimately I'd like to be able to playout using another blackmagic card. I can play out a local video file with

Code: Select all

ffmpeg -i videofile.mp4 -f decklink -pix_fmt uyvy422 'DeckLink SDI (1)'

but I can't figure out how to playout the receiving stream to the SDI output

AT FIRST .. add -re as a realtime encoding ..

and try multicast output :

-f mpegts "udp://239.101.101.1:1234?ttl=10&pkt_size=1316"

on second side try

ffmpeg -re -i "udp://239.101.101.1:1234?ttl=10&pkt_size=1316" -f decklink -pix_fmt uyvy422 'DeckLink SDI (1)'