Opened 3 weeks ago

Last modified 3 weeks ago

#7384 reopened defect

FFmpeg 4.0 does not set 5.1 surround sound into audio stream when converting mkv video with 5.1 surround sound

Reported by: itrdev Owned by:
Priority: important Component: avcodec
Version: git-master Keywords: aac
Cc: Blocked By:
Blocking: Reproduced by developer: no
Analyzed by developer: no

Description

Summary of the bug:

I upgraded ffmpeg to 4.0 version and found and issue that was not present in 3.4.2 version. When I convert MKV video with 5.1 surround sound audio ffmpeg gives an mp4 with audio that has channel_layout=unknown. As a result Windows and IE/Edge/Firefox browsers cannot play audio.
FFpmeg 3.4.2 gives a converted video with channel_layout=5.1. And audio is played without errors.

How to reproduce:

% ffmpeg.exe -noautorotate -i MKV.mkv -c:v libx264 -crf 31 -preset veryfast -y Mkv.mp4
ffmpeg version 4.0.2 Copyright (c) 2000-2018 the FFmpeg developers
  built with gcc 7.3.1 (GCC) 20180722
  configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-bzlib --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth
  libavutil      56. 14.100 / 56. 14.100
  libavcodec     58. 18.100 / 58. 18.100
  libavformat    58. 12.100 / 58. 12.100
  libavdevice    58.  3.100 / 58.  3.100
  libavfilter     7. 16.100 /  7. 16.100
  libswscale      5.  1.100 /  5.  1.100
  libswresample   3.  1.100 /  3.  1.100
  libpostproc    55.  1.100 / 55.  1.100
[aac @ 000001229524e580] This stream seems to incorrectly report its last channel as SCE[1], mapping to LFE[0]
Input #0, matroska,webm, from 'MKV.mkv':
  Metadata:
    encoder         : libebml v0.7.5 + libmatroska v0.7.7
    creation_time   : 2005-08-22T17:01:27.000000Z
  Duration: 00:00:30.85, start: 0.000000, bitrate: 1128 kb/s
    Stream #0:0: Video: mpeg4 (Simple Profile) (XVID / 0x44495658), yuv420p, 360x240 [SAR 3:2 DAR 9:4], SAR 1:1 DAR 3:2, 15 fps, 15 tbr, 1k tbn, 15 tbc (default)
    Metadata:
      title           : XviD Video Stream
    Stream #0:1(eng): Audio: ac3, 48000 Hz, 5.1(side), fltp, 192 kb/s (default)
    Metadata:
      title           : AC3 5.1 Test Audio
    Stream #0:2(eng): Audio: aac (HE-AAC), 48000 Hz, 5.1, fltp
    Metadata:
      title           : AAC 5.1 Test Audio
Stream mapping:
  Stream #0:0 -> #0:0 (mpeg4 (native) -> h264 (libx264))
  Stream #0:1 -> #0:1 (ac3 (native) -> aac (native))
Press [q] to stop, [?] for help
[aac @ 0000012295300e40] Using a PCE to encode channel layout
[mpeg4 @ 0000012295303b80] Video uses a non-standard and wasteful way to store B-frames ('packed B-frames'). Consider using the mpeg4_unpack_bframes bitstream filter without encoding but stream copy to fix it.
[libx264 @ 00000122956600c0] using SAR=1/1
[libx264 @ 00000122956600c0] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2
[libx264 @ 00000122956600c0] profile High, level 1.2
[libx264 @ 00000122956600c0] 264 - core 155 r2901 7d0ff22 - H.264/MPEG-4 AVC codec - Copyleft 2003-2018 - http://www.videolan.org/x264.html - options: cabac=1 ref=1 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=2 psy=1 psy_rd=1.00:0.00 mixed_ref=0 me_range=16 chroma_me=1 trellis=0 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=0 threads=6 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=1 keyint=250 keyint_min=15 scenecut=40 intra_refresh=0 rc_lookahead=10 rc=crf mbtree=1 crf=31.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
Output #0, mp4, to 'Mkv.mp4':
  Metadata:
    encoder         : Lavf58.12.100
    Stream #0:0: Video: h264 (libx264) (avc1 / 0x31637661), yuv420p, 360x240 [SAR 1:1 DAR 3:2], q=-1--1, 15 fps, 15360 tbn, 15 tbc (default)
    Metadata:
      title           : XviD Video Stream
      encoder         : Lavc58.18.100 libx264
    Side data:
      cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: -1
    Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, 5.1(side), fltp, 394 kb/s (default)
    Metadata:
      title           : AC3 5.1 Test Audio
      encoder         : Lavc58.18.100 aac
frame=  462 fps=136 q=-1.0 Lsize=    1658kB time=00:00:30.72 bitrate= 442.0kbits/s dup=1 drop=0 speed=9.03x
video:343kB audio:1298kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 1.030490%
[libx264 @ 00000122956600c0] frame I:14    Avg QP:26.16  size:  1752
[libx264 @ 00000122956600c0] frame P:179   Avg QP:28.83  size:  1026
[libx264 @ 00000122956600c0] frame B:269   Avg QP:30.51  size:   530
[libx264 @ 00000122956600c0] consecutive B-frames: 17.5% 10.8% 11.0% 60.6%
[libx264 @ 00000122956600c0] mb I  I16..4: 32.5% 56.3% 11.2%
[libx264 @ 00000122956600c0] mb P  I16..4: 17.6% 24.2%  2.5%  P16..4: 11.3%  5.7%  2.6%  0.0%  0.0%    skip:36.0%
[libx264 @ 00000122956600c0] mb B  I16..4:  2.0%  4.9%  0.3%  B16..8: 13.6%  6.4%  0.8%  direct: 3.3%  skip:68.7%  L0:40.2% L1:42.7% BI:17.1%
[libx264 @ 00000122956600c0] 8x8 transform intra:57.2% inter:34.3%
[libx264 @ 00000122956600c0] coded y,uvDC,uvAC intra: 29.5% 18.8% 2.1% inter: 4.5% 5.9% 0.1%
[libx264 @ 00000122956600c0] i16 v,h,dc,p: 38% 34%  9% 19%
[libx264 @ 00000122956600c0] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 15% 39% 28%  3%  2%  3%  3%  4%  3%
[libx264 @ 00000122956600c0] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 22% 23% 17%  7%  6%  6%  6%  7%  5%
[libx264 @ 00000122956600c0] i8c dc,h,v,p: 67% 23%  8%  2%
[libx264 @ 00000122956600c0] Weighted P-Frames: Y:7.8% UV:4.5%
[libx264 @ 00000122956600c0] kb/s:91.08
[aac @ 0000012295300e40] Qavg: 31339.592

FFprobe output for ffpmeg 4.0

% ffprobe -show_streams MKV.mp4
ffprobe version 4.0.2 Copyright (c) 2007-2018 the FFmpeg developers
  built with gcc 7.3.1 (GCC) 20180722
  configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-bzlib --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth
  libavutil      56. 14.100 / 56. 14.100
  libavcodec     58. 18.100 / 58. 18.100
  libavformat    58. 12.100 / 58. 12.100
  libavdevice    58.  3.100 / 58.  3.100
  libavfilter     7. 16.100 /  7. 16.100
  libswscale      5.  1.100 /  5.  1.100
  libswresample   3.  1.100 /  3.  1.100
  libpostproc    55.  1.100 / 55.  1.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'MKV.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf58.12.100
  Duration: 00:00:30.80, start: 0.000000, bitrate: 440 kb/s
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 360x240 [SAR 1:1 DAR 3:2], 91 kb/s, 15 fps, 15 tbr, 15360 tbn, 30 tbc (default)
    Metadata:
      handler_name    : VideoHandler
    Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, 6 channels, fltp, 345 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
[STREAM]
index=0
codec_name=h264
codec_long_name=H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10
profile=High
codec_type=video
codec_time_base=1/30
codec_tag_string=avc1
codec_tag=0x31637661
width=360
height=240
coded_width=368
coded_height=240
has_b_frames=2
sample_aspect_ratio=1:1
display_aspect_ratio=3:2
pix_fmt=yuv420p
level=12
color_range=unknown
color_space=unknown
color_transfer=unknown
color_primaries=unknown
chroma_location=left
field_order=unknown
timecode=N/A
refs=1
is_avc=true
nal_length_size=4
id=N/A
r_frame_rate=15/1
avg_frame_rate=15/1
time_base=1/15360
start_pts=0
start_time=0.000000
duration_ts=473088
duration=30.800000
bit_rate=91261
max_bit_rate=N/A
bits_per_raw_sample=8
nb_frames=462
nb_read_frames=N/A
nb_read_packets=N/A
DISPOSITION:default=1
DISPOSITION:dub=0
DISPOSITION:original=0
DISPOSITION:comment=0
DISPOSITION:lyrics=0
DISPOSITION:karaoke=0
DISPOSITION:forced=0
DISPOSITION:hearing_impaired=0
DISPOSITION:visual_impaired=0
DISPOSITION:clean_effects=0
DISPOSITION:attached_pic=0
DISPOSITION:timed_thumbnails=0
TAG:language=und
TAG:handler_name=VideoHandler
[/STREAM]
[STREAM]
index=1
codec_name=aac
codec_long_name=AAC (Advanced Audio Coding)
profile=LC
codec_type=audio
codec_time_base=1/48000
codec_tag_string=mp4a
codec_tag=0x6134706d
sample_fmt=fltp
sample_rate=48000
channels=6
channel_layout=unknown
bits_per_sample=0
id=N/A
r_frame_rate=0/0
avg_frame_rate=0/0
time_base=1/48000
start_pts=0
start_time=0.000000
duration_ts=1474560
duration=30.720000
bit_rate=345780
max_bit_rate=394000
bits_per_raw_sample=N/A
nb_frames=1441
nb_read_frames=N/A
nb_read_packets=N/A
DISPOSITION:default=1
DISPOSITION:dub=0
DISPOSITION:original=0
DISPOSITION:comment=0
DISPOSITION:lyrics=0
DISPOSITION:karaoke=0
DISPOSITION:forced=0
DISPOSITION:hearing_impaired=0
DISPOSITION:visual_impaired=0
DISPOSITION:clean_effects=0
DISPOSITION:attached_pic=0
DISPOSITION:timed_thumbnails=0
TAG:language=eng
TAG:handler_name=SoundHandler
[/STREAM]

FFprobe output for ffpmeg 3.4.2

% ffprobe -show_streams MKV.mp4
ffprobe version 4.0.2 Copyright (c) 2007-2018 the FFmpeg developers
  built with gcc 7.3.1 (GCC) 20180722
  configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-bzlib --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth
  libavutil      56. 14.100 / 56. 14.100
  libavcodec     58. 18.100 / 58. 18.100
  libavformat    58. 12.100 / 58. 12.100
  libavdevice    58.  3.100 / 58.  3.100
  libavfilter     7. 16.100 /  7. 16.100
  libswscale      5.  1.100 /  5.  1.100
  libswresample   3.  1.100 /  3.  1.100
  libpostproc    55.  1.100 / 55.  1.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'MKV.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf57.83.100
  Duration: 00:00:30.80, start: 0.000000, bitrate: 436 kb/s
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 360x240 [SAR 1:1 DAR 3:2], 91 kb/s, 15 fps, 15 tbr, 15360 tbn, 30 tbc (default)
    Metadata:
      handler_name    : VideoHandler
    Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, 5.1, fltp, 341 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
[STREAM]
index=0
codec_name=h264
codec_long_name=H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10
profile=High
codec_type=video
codec_time_base=1/30
codec_tag_string=avc1
codec_tag=0x31637661
width=360
height=240
coded_width=368
coded_height=240
has_b_frames=2
sample_aspect_ratio=1:1
display_aspect_ratio=3:2
pix_fmt=yuv420p
level=12
color_range=unknown
color_space=unknown
color_transfer=unknown
color_primaries=unknown
chroma_location=left
field_order=unknown
timecode=N/A
refs=1
is_avc=true
nal_length_size=4
id=N/A
r_frame_rate=15/1
avg_frame_rate=15/1
time_base=1/15360
start_pts=0
start_time=0.000000
duration_ts=473088
duration=30.800000
bit_rate=91261
max_bit_rate=N/A
bits_per_raw_sample=8
nb_frames=462
nb_read_frames=N/A
nb_read_packets=N/A
DISPOSITION:default=1
DISPOSITION:dub=0
DISPOSITION:original=0
DISPOSITION:comment=0
DISPOSITION:lyrics=0
DISPOSITION:karaoke=0
DISPOSITION:forced=0
DISPOSITION:hearing_impaired=0
DISPOSITION:visual_impaired=0
DISPOSITION:clean_effects=0
DISPOSITION:attached_pic=0
DISPOSITION:timed_thumbnails=0
TAG:language=und
TAG:handler_name=VideoHandler
[/STREAM]
[STREAM]
index=1
codec_name=aac
codec_long_name=AAC (Advanced Audio Coding)
profile=LC
codec_type=audio
codec_time_base=1/48000
codec_tag_string=mp4a
codec_tag=0x6134706d
sample_fmt=fltp
sample_rate=48000
channels=6
channel_layout=5.1
bits_per_sample=0
id=N/A
r_frame_rate=0/0
avg_frame_rate=0/0
time_base=1/48000
start_pts=0
start_time=0.000000
duration_ts=1474560
duration=30.720000
bit_rate=341279
max_bit_rate=341279
bits_per_raw_sample=N/A
nb_frames=1441
nb_read_frames=N/A
nb_read_packets=N/A
DISPOSITION:default=1
DISPOSITION:dub=0
DISPOSITION:original=0
DISPOSITION:comment=0
DISPOSITION:lyrics=0
DISPOSITION:karaoke=0
DISPOSITION:forced=0
DISPOSITION:hearing_impaired=0
DISPOSITION:visual_impaired=0
DISPOSITION:clean_effects=0
DISPOSITION:attached_pic=0
DISPOSITION:timed_thumbnails=0
TAG:language=eng
TAG:handler_name=SoundHandler
[/STREAM]

It looks like a defect because it worked in 3.4.2 version. I'm waiting for response. Thanks

Change History (9)

comment:2 Changed 3 weeks ago by jamrial

  • Component changed from ffmpeg to avcodec
  • Keywords aac added; ffmpeg 5.1 surround audio removed
  • Priority changed from normal to important
  • Status changed from new to open
  • Version changed from unspecified to git-master

Seems to be a regression since fc9dcfe7d50d7f1b38fb287b4d92b5f3fc4bfb05

comment:3 Changed 3 weeks ago by atomnuker

  • Resolution set to invalid
  • Status changed from open to closed

The issue is that the file signals a layout of 5.1(side), but the AAC spec only supports 5.1(rear channels instead of side). Hence, to express that the encoder uses a not-so-universally supported feature to signal the non-standard layout. Firefox 62.0 here supports decoding it just fine, so maybe whatever you're using is old.
You can convert between 5.1(side) and 5.1(rear) by specifying -channel_layout "5.1", which will make the encoder use the standard well understood path.

Last edited 3 weeks ago by atomnuker (previous) (diff)

comment:4 Changed 3 weeks ago by itrdev

But why it's working fine in ffmpeg 3.4.2? Were there any breaking changes in ffmpeg 4.0 connected to this?

comment:5 Changed 3 weeks ago by itrdev

Last edited 3 weeks ago by itrdev (previous) (diff)

comment:6 Changed 3 weeks ago by itrdev

Last edited 3 weeks ago by itrdev (previous) (diff)

comment:7 Changed 3 weeks ago by itrdev

Additional question: what should I do with ffmpeg 4 if input can contain videos with different channels layouts? In 3.4.2 ffmpeg desided what to do but in 4.0 this issue exists.

comment:8 Changed 3 weeks ago by itrdev

  • Resolution invalid deleted
  • Status changed from closed to reopened

I reopened this issue because maybe closed issues are not tracked for additional response. Thanks!

comment:9 Changed 3 weeks ago by itrdev

My general question is how I should convert videos with different channels layouts to save theirs layouts with ffmpeg 4.

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