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I'm using VLC - 2.2.2 on Ubuntu 16.04. VLC is able to play the videos but I'm unable to take the snapshots using it. I tried disabling "Use Hardware Acceleration" by going in Preferences->Video and changing the output to OpenGL (GLX), OpenGL 2 and XVideo,one by one, the later resulted in a black screen.

When I try to capture a snapshot I get this error:

[00007f9440d10248] avcodec decoder: Using NVIDIA VDPAU Driver Shared Library  361.42  Tue Mar 22 17:29:16 PDT 2016 for hardware decoding.
[00007f946c509148] vdpau_chroma filter error: corrupt VDPAU video surface 0x7f94208e4950
[00007f94300fca08] core video output error: Failed to convert image for snapshot

Is there a way to tell VLC not to use Hardware Acceleration? My intention is to remain with Hardware Acceleration disabled for now.

Hatoru Hansou
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    VLC bug report: https://trac.videolan.org/vlc/ticket/14456 – cweiske Jan 07 '17 at 13:25
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    Forum thread from 2015: https://forum.videolan.org/viewtopic.php?t=129067 – cweiske Jan 07 '17 at 13:26
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    another workaround: http://matt.coneybeare.me/how-to-generate-png-screenshots-using-ffmpeg/ – TiloBunt Nov 27 '20 at 06:23
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    I used: ffmpeg -i input.mp4 -ss 00:00:32 -vframes 1 output.jpg – TiloBunt Nov 27 '20 at 06:30
  • @TiloBunt Yes, ffmpeg can do it. But I had, very ocassionally, problems with how VLC and ffmpeg seek to a given position. Sometimes, the frame saved to file is not the one I expect. This may happen by a variety of reasons. Maybe VLC gui only show position to seconds precision, but you are at 00:00:15.345, but you don't have a way to know it. Then you tell ffmpeg to seek to 00:00:15, and you get the wrong frame. – Hatoru Hansou Nov 27 '20 at 14:18
  • agree not ideal. But VLC didn't work for me. Btw in the cmd you can go down to mil sec -ss 00:00:32.300 but still hard to get the exact one. – TiloBunt Nov 27 '20 at 22:17

1 Answers1

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Answering myself.

The option at Preferences->Video->Use Hardware Acceleration controls how graphics are drawn on screen, not how videos are decoded. The option to disable VDPAU is at Preferences->Input & Codecs. Then look for "Hardware accelerated decoding" and change VDPAU for any of the other options, I'm using X11 VA-API.

And problem solved. I can take snapshots again. I will remain with Hardware decoding disabled until the problem is fixed, probably at the side of the VDPAU driver library (just guessing). No perceptible lag while playing videos so far.

Hatoru Hansou
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