[MPlayer-dev-eng] Possible libavcodec encoding bug (keyframe thing)

[Pásztor Szilárd]

Hi,

  Possible bug in libavcodec mpeg4 encoder: series of keyframes on occasion.
I've put up a sample of an encoded MPEG2 part and there are keyframe bursts
for longer periods without obvious reason (it's almost a stand-still scene).
Sample files: keyframe-orig.avi, keyframe-encoded.avi (in incoming),
modified mplayer (to report keyframes) playback log in keyframe-report.txt.

mencoder: CVS-020820 (same effect as with pre6)
dist: RH 7.3, Debian 3.0
kernel: 2.4.18
glibc-2.2.5
gcc-2.95-4
ld: 2.11.93.0.2
as: 2.11.93.0.2

Command line used for encoding: mencoder -ovc lavc -oac copy -lavcopts \
vcodec=mpeg4:keyint=350:vbitrate=1500:vqmin=2:vqmax=30:vqdiff=15:vhq:vqblur=0:vqcomp=0.6:v4mv:vpass=1..2 \
-vop [crop,scale etc] -sws 2 -o encoded.avi

In the sample encoded avi, each frame is a keyframe beginning from 26
seconds into the movie to 28.4 seconds (low-mo scene), from 70.4 seconds to
71.3, 74.6-75.4, 86.2-86.6, 122-122.5, then 135-145.

s.
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