iPod / iPad plays both audio tracks simultaneously

[TonyPh12345]

This is very similar to portions of what's described in #468.

The input MKV file has one AVC video track and two AC3 audio tracks.

I use this command (in ffmpeg 0.10.2; see below for results with today's git)

ffmpeg -y -i input.mkv -map 0:0 -map 0:1 -map 0:2 -acodec aac -ar 48000 -ab 128k -ac 2 -vcodec copy -strict experimental -threads 6 output.m4v

The process runs, and no errors are reported

ffmpeg started on 2012-04-06 at 15:59:59
Report written to "ffmpeg-20120406-155959.log"
Command line:
ffmpeg -report -y -i input.mkv -map 0:0 -map 0:1 -map 0:2 -acodec aac -ar 48000 -ab 128k -ac 2 -vcodec copy -strict experimental -threads 6 output.m4v
ffmpeg version 0.10.2 Copyright (c) 2000-2012 the FFmpeg developers
  built on Mar 24 2012 15:22:08 with gcc 4.5.1 20100924 (Red Hat 4.5.1-4)
  configuration:
  libavutil      51. 35.100 / 51. 35.100
  libavcodec     53. 61.100 / 53. 61.100
  libavformat    53. 32.100 / 53. 32.100
  libavdevice    53.  4.100 / 53.  4.100
  libavfilter     2. 61.100 /  2. 61.100
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0.  6.100 /  0.  6.100
[matroska,webm @ 0xa058280] Format matroska,webm probed with size=2048 and score=100
st:0 removing common factor 1000000 from timebase
st:1 removing common factor 1000000 from timebase
st:2 removing common factor 1000000 from timebase
st:3 removing common factor 1000000 from timebase
st:4 removing common factor 1000000 from timebase
st:5 removing common factor 1000000 from timebase
[h264 @ 0xa05f4c0] err{or,}_recognition separate: 1; 1
[h264 @ 0xa05f4c0] err{or,}_recognition combined: 1; 10001
[ac3 @ 0xa05fb60] err{or,}_recognition separate: 1; 1
[ac3 @ 0xa05fb60] err{or,}_recognition combined: 1; 10001
[ac3 @ 0xa05fb60] Unsupported bit depth: 0
[ac3 @ 0xa060140] err{or,}_recognition separate: 1; 1
[ac3 @ 0xa060140] err{or,}_recognition combined: 1; 10001
[ac3 @ 0xa060140] Unsupported bit depth: 0
[dvdsub @ 0xa079a00] err{or,}_recognition separate: 1; 1
[dvdsub @ 0xa079a00] err{or,}_recognition combined: 1; 10001
[dvdsub @ 0xa079a00] palette: 0x0000fd 0xfe0000 0x000000 0xfdfdfd 0xf38200 0x0087f4 0xf6ea8a 0x007c7b 0x0000fd 0xfeea04 0x7b0000 0x007e00 0x00007a 0xdc00fd 0xdd7d00 0xdfe13a
[dvdsub @ 0xa07fc80] err{or,}_recognition separate: 1; 1
[dvdsub @ 0xa07fc80] err{or,}_recognition combined: 1; 10001
[dvdsub @ 0xa07fc80] palette: 0x0000fd 0xfe0000 0x000000 0xfdfdfd 0xf38200 0x0087f4 0xf6ea8a 0x007c7b 0x0000fd 0xfeea04 0x7b0000 0x007e00 0x00007a 0xdc00fd 0xdd7d00 0xdfe13a
[h264 @ 0xa05f4c0] no picture
[h264 @ 0xa05f4c0] no picture
[matroska,webm @ 0xa058280] All info found
rfps: 29.666667 0.013781
rfps: 29.666667 0.013781
rfps: 29.750000 0.007295
rfps: 29.750000 0.007295
rfps: 29.833333 0.002869
rfps: 29.833333 0.002869
rfps: 29.916667 0.000504
rfps: 29.916667 0.000504
rfps: 30.000000 0.000199
rfps: 30.083333 0.001955
rfps: 30.166667 0.005771
rfps: 30.250000 0.011647
rfps: 30.333333 0.019584
rfps: 30.333333 0.019584
rfps: 59.583333 0.019298
rfps: 59.666667 0.011477
rfps: 59.666667 0.011477
rfps: 59.750000 0.005717
rfps: 59.750000 0.005717
rfps: 59.833333 0.002017
rfps: 59.833333 0.002017
rfps: 59.916667 0.000377
rfps: 59.916667 0.000377
rfps: 29.970030 0.000072
rfps: 29.970030 0.000072
rfps: 59.940060 0.000287
rfps: 59.940060 0.000287
Input #0, matroska,webm, from 'input.mkv':
  Duration: 00:22:01.32, start: 0.000000, bitrate: 1705 kb/s
    Chapter #0.0: start 0.000000, end 330.330000
    Metadata:
      title           : Chapter 1
    Chapter #0.1: start 330.330000, end 859.325133
    Metadata:
      title           : Chapter 2
    Chapter #0.2: start 859.325133, end 1295.360733
    Metadata:
      title           : Chapter 3
    Chapter #0.3: start 1295.360733, end 1321.320000
    Metadata:
      title           : Chapter 4
    Stream #0:0(eng), 43, 1/1000: Video: h264 (Main), yuv420p, 720x480 [SAR 8:9 DAR 4:3], 29.97 fps, 29.97 tbr, 1k tbn, 180k tbc (default)
    Stream #0:1(eng), 46, 1/1000: Audio: ac3, 48000 Hz, 5.1(side), s16, 384 kb/s (default)
    Stream #0:2(eng), 46, 1/1000: Audio: ac3, 48000 Hz, mono, s16, 96 kb/s
    Stream #0:3(eng), 0, 1/1000: Subtitle: dvd_subtitle
    Stream #0:4(eng), 0, 1/1000: Subtitle: dvd_subtitle
    Stream #0:5(eng), 0, 1/1000: Subtitle: text
Incompatible sample format 's16' for codec 'aac', auto-selecting format 'flt'
Incompatible sample format 's16' for codec 'aac', auto-selecting format 'flt'
[aac @ 0xa0e4c80] err{or,}_recognition separate: 1; 1
[aac @ 0xa0e4c80] err{or,}_recognition combined: 1; 10001
[aac @ 0xa0e4c80] Unsupported bit depth: 0
[aac @ 0xa0a5340] err{or,}_recognition separate: 1; 1
[aac @ 0xa0a5340] err{or,}_recognition combined: 1; 10001
[aac @ 0xa0a5340] Unsupported bit depth: 0
[ac3 @ 0xa05fb60] err{or,}_recognition separate: 1; 10001
[ac3 @ 0xa05fb60] err{or,}_recognition combined: 1; 10001
[ac3 @ 0xa05fb60] Unsupported bit depth: 0
[ac3 @ 0xa060140] err{or,}_recognition separate: 1; 10001
[ac3 @ 0xa060140] err{or,}_recognition combined: 1; 10001
[ac3 @ 0xa060140] Unsupported bit depth: 0
Output #0, ipod, to 'output.m4v':
  Metadata:
    encoder         : Lavf53.32.100
    Chapter #0.0: start 0.000000, end 330.330000
    Metadata:
      title           : Chapter 1
    Chapter #0.1: start 330.330000, end 859.325133
    Metadata:
      title           : Chapter 2
    Chapter #0.2: start 859.325133, end 1295.360733
    Metadata:
      title           : Chapter 3
    Chapter #0.3: start 1295.360733, end 1321.320000
    Metadata:
      title           : Chapter 4
    Stream #0:0(eng), 0, 1/1000: Video: h264 (avc1 / 0x31637661), yuv420p, 720x480 [SAR 8:9 DAR 4:3], q=2-31, 29.97 fps, 1k tbn, 1k tbc (default)
    Stream #0:1(eng), 0, 1/48000: Audio: aac (mp4a / 0x6134706D), 48000 Hz, 2 channels, flt, 128 kb/s (default)
    Stream #0:2(eng), 0, 1/48000: Audio: aac (mp4a / 0x6134706D), 48000 Hz, 2 channels, flt, 128 kb/s
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
  Stream #0:1 -> #0:1 (ac3 -> aac)
  Stream #0:2 -> #0:2 (ac3 -> aac)
Press [q] to stop, [?] for help
Input stream #0:1 frame changed from rate:48000 fmt:s16 ch:6 to rate:48000 fmt:s16 ch:2
0.707107
0.707107
frame=39600 fps=242 q=-1.0 Lsize=  236894kB time=00:22:01.22 bitrate=1468.8kbits/s
video:193780kB audio:41301kB global headers:0kB muxing overhead 0.770842%

But when I watch these files on iPod Touch or iPad (both running iOS 5.1) BOTH audio tracks play simultaneously.

If I access the Audio Track chooser in the video player, NEITHER track is "Checkmarked." If I then select either track, playback is normal.

It just seems like there's no "Default" flag set or something.

I don't understand the M4V format enough to debug in detail.

The same MKV converted to M4V using HandBrake 0.9.5 and the iPad preset works correctly.

I have tried this with multiple files using ffmpeg 0.10.2.
I cannot try with today's GIT (4/6/12) because using the exact same command, I get the error

Application provided invalid, non monotonically increasing dts to muxer in stream 0: -67 >= -67
av_interleaved_write_frame(): Invalid argument

[Carl Eugen Hoyos]

Replying to TonyPh12345:

I cannot try with today's GIT (4/6/12) because using the exact same command, I get the error

Application provided invalid, non monotonically increasing dts to muxer in stream 0: -67 >= -67
av_interleaved_write_frame(): Invalid argument

This sounds like a serious regression, please provide a sample.

[TonyPh12345]

I've uploaded a file named "Ticket1174.mkv" to the FTP server.
It's the entire file, not a 10M dd since some of the relevant metadata is at the end of the file.

[TonyPh12345]

Replying to cehoyos:

This sounds like a serious regression, please provide a sample.

Ooops; didn't hit the REPLY button. Trying again.

File uploaded.

[Carl Eugen Hoyos]

You can use -vcodec mpeg4 instead of -vcodec copy to test if the audio issue is still reproducible with current git head.
Did you test the patch in ticket #468? You may need to git checkout 62101030c4ff23c61046a70cd27a627dfb0e0e54 to be able to apply the patch.

[TonyPh12345]

Replying to cehoyos:

You can use -vcodec mpeg4 instead of -vcodec copy to test if the audio issue is still reproducible with current git head.
Did you test the patch in ticket #468? You may need to git checkout 62101030c4ff23c61046a70cd27a627dfb0e0e54 to be able to apply the patch.

Using the -vcodec mpeg4 did indeed allow the GIT clone to run. However, no fix for the audio as-is.

Since I'm a complete git-iot, I just hand-edited the patch from 468 into the two files in the git clone and recompiled... It worked. iPad and iPod both played the file correctly.

Unfortunately, the source-code differences between the GIT and the 0.10.2 are too substantial for me to the just re-use the edited movenc.c and movenc.h in the 10.2 build... won't compile. :(

Is there any branch that would get me far enough to keep using the -vcodec COPY option, while keeping the patch? (-copy runs about 8x faster than re-encoding to MP4... and I have about 3000 files I want to run this against.)

[TonyPh12345]

Oh, interesting.

Just as a quick & dirty HACK, all I needed to do was change (in utils.c at line 3138)

if(st->cur_dts && st->cur_dts != AV_NOPTS_VALUE && ((!(s->oformat->flags & AVFMT_TS_NONSTRICT) && st->cur_dts >= pkt->dts)

st->cur_dts > pkt->dts)){

to

if(st->cur_dts && st->cur_dts != AV_NOPTS_VALUE && ((!(s->oformat->flags & AVFMT_TS_NONSTRICT) && st->cur_dts > pkt->dts)

st->cur_dts > pkt->dts)){

(changed the equality to an inequality) to get past the error in the GIT clone.

I realize that's not a "Fix," but it gets me where I need to be.

[Elon Musk]

This appears to be fixed. Please reopen if not.

[Carl Eugen Hoyos]

Afaict this is a duplicate of ticket #468, still reproducible with the following command line:

$ ffmpeg -i fate-suite/svq3/Vertical400kbit.sorenson3.mov -i fate-suite/aac/al_sbr_cm_48_5.1.mp4 -map 0:0 -map 0:1 -map 1:0 -acodec aac -strict -2 -vcodec mpeg4 -qscale 5 out.m4v