Using the current ffmpeg SVN version (SVN-r19439 as of 7/15/09), I receive the
following error when trying to transcode an h264 video from mkv to m4v.

av_interleaved_write_frame(): Error while opening file

The sample file includes a dts track which converts fine to ac3 so that's not
causing the problem. There was a similar bug reported and fixed in February
(Item 872) which saw the same error for an encode using libx264.

Below are the command and full output. Sample file is being uploaded to MPlayer
FTP site. Thanks!


hhasanmacmini:Downloads hhasan$ ffmpeg -i small_h264.mkv -vcodec copy -acodec
ac3 -ab 640k h264video.m4v
FFmpeg version SVN-r19439, Copyright (c) 2000-2009 Fabrice Bellard, et al.
  configuration: 
  libavutil     50. 3. 0 / 50. 3. 0
  libavcodec    52.32. 0 / 52.32. 0
  libavformat   52.36. 0 / 52.36. 0
  libavdevice   52. 2. 0 / 52. 2. 0
  libswscale     0. 7. 1 /  0. 7. 1
  built on Jul 15 2009 17:58:26, gcc: 4.0.1 (Apple Inc. build 5490)

Seems stream 0 codec frame rate differs from container frame rate: 47.95
(27956/583) -> 23.98 (24000/1001)
Input #0, matroska, from 'small_h264.mkv':
  Duration: 00:00:58.72, start: 0.000000, bitrate: N/A
    Stream #0.0(eng): Video: h264, yuv420p, 1280x688, PAR 1:1 DAR 80:43, 23.98
tbr, 1k tbn, 47.95 tbc
    Stream #0.1(eng): Audio: dca, 48000 Hz, 6 channels, s16
    Stream #0.2(swe): Subtitle: 0x0000
    Stream #0.3(dan): Subtitle: 0x0000
    Stream #0.4(eng): Subtitle: 0x0000
    Stream #0.5(est): Subtitle: 0x0000
    Stream #0.6(fin): Subtitle: 0x0000
    Stream #0.7(fre): Subtitle: 0x0000
    Stream #0.8(ger): Subtitle: 0x0000
    Stream #0.9(ita): Subtitle: 0x0000
    Stream #0.10(nor): Subtitle: 0x0000
    Stream #0.11(por): Subtitle: 0x0000
    Stream #0.12(slv): Subtitle: 0x0000
    Stream #0.13(spa): Subtitle: 0x0000
    Stream #0.14: Attachment: 0x0000
    Stream #0.15: Attachment: 0x0000
    Stream #0.16: Attachment: 0x0000
[ac3 @ 0x10fba00]No channel layout specified. The encoder will guess the layout,
but it might be incorrect.
Output #0, ipod, to 'h264video.m4v':
    Stream #0.0(eng): Video: avc1 / 0x31637661, yuv420p, 1280x688 [PAR 1:1 DAR
80:43], q=2-31, 1k tbn, 1k tbc
    Stream #0.1(eng): Audio: ac3, 48000 Hz, 5.1, s16, 640 kb/s
Stream mapping:
  Stream #0.0 -> #0.0
  Stream #0.1 -> #0.1
Press [q] to stop encoding
[NULL @ 0x10bf400]error, non monotone timestamps 125 >= 83
av_interleaved_write_frame(): Error while opening file