[FFmpeg-trac] #5732(avcodec:open): Display corruption on very high-bitrate H.264 files

FFmpeg trac at avcodec.org
Sun Jul 24 22:08:39 EEST 2016

#5732: Display corruption on very high-bitrate H.264 files
             Reporter:  Sesse       |                    Owner:
                 Type:  defect      |                   Status:  open
             Priority:  minor       |                Component:  avcodec
              Version:  git-master  |               Resolution:
             Keywords:  h264        |               Blocked By:
             Blocking:              |  Reproduced by developer:  1
Analyzed by developer:  0           |

Comment (by Sesse):

 Well, yes and no. The stream is encoded at constant quantizer 15, which
 for the content I'm interested in is as good as visually lossless.
 Normally, for me, this does indeed yield streams around 25 Mbit/sec, but
 this specific demo is an outlier (I like to call these “streamkillers”; I
 guess you can understand why), and I've seen it spike to 170 Mbit/sec or
 so in parts.

 I understand that the error is probably on the encoding side, which is a
 bit of a bummer. I wonder if I can somehow reproduce it without recreating
 the lossless input (perhaps just take the input and reencode at similar
 quantizer?). Of course, this sounds more like a hardware bug than anything
 else, then, and those are by nature hard to fix :-) It would be
 interesting to see if e.g. Skylake has the same issue, though; AIUI, they
 keep improving the QSV encoder.

Ticket URL: <https://trac.ffmpeg.org/ticket/5732#comment:15>
FFmpeg <https://ffmpeg.org>
FFmpeg issue tracker

More information about the FFmpeg-trac mailing list