avvideodec: outputs gray frames for non-keyframes when configured to operate in TRICKMODE_KEYUNIT
Submitted by Tim Müller
Make sure e.g. avdec_h264 is used.
Press 't' three times until it says '(trick mode: key frames only)'
The output is gray frames with occasionally a picture showing up (presumably where there's a keyframe).
What should happen:
Only decoded key frames should be output, no gray frames in between.
This works fine if the demuxer is aware of the trick mode and only outputs keyframes in the first place of course (like qtdemux does).
Note that the demuxer flags buffers correctly as key-frame/delta-unit here.
It's just that libav appears to output gray frames for non-keyframes.
I'm not sure if this is a bug in libav or if we're supposed to look at the pict_type and drop the frame in avviddec if needed (which we can easily do of course).