[FFmpeg-trac] #7882(avdevice:new): Decklink 4k Extreme output "not enough buffered video frames"

[FFmpeg]

#7882: Decklink 4k Extreme output "not enough buffered video frames"
-------------------------------------+-------------------------------------
             Reporter:  flaneur      |                     Type:  defect
               Status:  new          |                 Priority:  normal
            Component:  avdevice     |                  Version:
                                     |  unspecified
             Keywords:  decklink 4k  |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 Summary of the bug:
 Sending video out "Decklink 4k Extreme" SDI/HDMI video card does not work
 properly, produces the following error repeatedly:

 [decklink @ 0xf0b200] There are not enough buffered video frames. Video
 may misbehave!

 How to reproduce:
 Ubuntu 18.04,
 kernel 4.15.0-48-lowlatency,
 Blackmagic Desktopvideo 11.1,
 FFmpeg snapshot git commit fcc01ba,
 Blackmagic Decklink SDK 11.1

 FFmpeg was compiled and run as a Docker image based on jrottenberg/ffmpeg
 ubuntu build. The modified Docker source is here:
 https://github.com/flaneurtv/ffmpeg

 The Docker image is publicly available for testing:
 https://cloud.docker.com/u/flaneurtv/repository/docker/flaneurtv/ffmpeg

 The tags used for testing this were:
 4.1-sdk-10.11.4
 snapshot-sdk-11.1

 Install the respective Decklink SDK on your host system, then run:

 {{{
 docker run -it --device=/dev/blackmagic:/dev/blackmagic -v
 /srv/assets:/srv/assets -v
 /etc/blackmagic/BlackmagicPreferences.xml:/etc/blackmagic/BlackmagicPreferences.xml
 flaneurtv/ffmpeg:snapshot-sdk-11.1 -f lavfi -i
 testsrc2=size=3840x2160:rate=25 -f decklink -pix_fmt uyvy422 'DeckLink 4K
 Extreme'
 }}}

 The problem is the same, when using flaneurtv/ffmpeg:4.1-sdk-10.11.4 and
 the respective drivers on the host system.

 Running ffmpeg with decklink in Docker is known to work. I am using this
 setup for years now, so this most certainly can be ruled out as the source
 of the problem.

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Ticket URL: <https://trac.ffmpeg.org/ticket/7882>
FFmpeg <https://ffmpeg.org>
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