[FFmpeg-trac] #2696(undetermined:new): Audio/Video sync issues when reducing fps from 59.94 to 29.97

FFmpeg trac at avcodec.org
Fri Jun 21 09:22:40 CEST 2013


#2696: Audio/Video sync issues when reducing fps from 59.94 to 29.97
-------------------------------------+-------------------------------------
             Reporter:  smblr75      |                     Type:  defect
               Status:  new          |                 Priority:  normal
            Component:               |                  Version:
  undetermined                       |  unspecified
             Keywords:               |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 Summary of the bug:
 When I transcode the source video (dejavu_20mb.mp4) which is at 59.97 fps
 down to 29.97 fps (dejavu_2997.mp4), I can see some lip sync issues
 indicating that there is some audio/video sync issue.
 I don't see any problem when I transcode at the same fps (dejavu_5994.mp4)

 How to reproduce:
 {{{
 ffmpeg -i dejavu_20mb.mp4 -r 29.97 dejavu_2997.mp4
 ffmpeg version 1.1 Copyright (c) 2000-2013 the FFmpeg developers
   built on May 27 2013 10:30:08 with gcc 3.4.6 (GCC) 20060404 (Red Hat
 3.4.6-9)
   configuration: --enable-gpl --enable-version3 --enable-zlib --enable-
 bzlib --enable-pthreads --enable-libvorbis --enable-libtheora --enable-
 libspeex --enable-libmp3lame --enable-libxvid --enable-libx264 --enable-
 libopencore_amrwb --enable-libopencore_amrnb --enable-libfdk_aac --enable-
 libvpx --enable-libgsm --extra-libs=-static --enable-nonfree --enable-
 libfreetype
   libavutil      52. 13.100 / 52. 13.100
   libavcodec     54. 86.100 / 54. 86.100
   libavformat    54. 59.106 / 54. 59.106
   libavdevice    54.  3.102 / 54.  3.102
   libavfilter     3. 32.100 /  3. 32.100
   libswscale      2.  1.103 /  2.  1.103
   libswresample   0. 17.102 /  0. 17.102
   libpostproc    52.  2.100 / 52.  2.100
 Guessed Channel Layout for  Input Stream #0.0 : stereo
 Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'dejavu_20mb.mp4':
   Metadata:
     major_brand     : qt
     minor_version   : 537199360
     compatible_brands: qt
     creation_time   : 2013-06-10 21:03:17
   Duration: 00:02:41.34, start: 0.000000, bitrate: 1039 kb/s
     Stream #0:0(eng): Audio: pcm_s16le (sowt / 0x74776F73), 48000 Hz,
 stereo, s16, 1536 kb/s
     Metadata:
       creation_time   : 2013-06-10 21:10:02
       handler_name    : Apple Alias Data Handler
     Stream #0:1(eng): Video: h264 (Main) (avc1 / 0x31637661), yuv420p,
 1280x720, 8684 kb/s, 59.94 fps, 59.94 tbr, 5994 tbn, 11988 tbc
     Metadata:
       creation_time   : 2013-06-10 21:10:02
       handler_name    : Apple Alias Data Handler
 [libx264 @ 0x1cc905e0] using cpu capabilities: MMX2 SSE2Fast SSSE3
 FastShuffle SSE4.1 Cache64
 [libx264 @ 0x1cc905e0] profile High, level 3.1
 [libx264 @ 0x1cc905e0] 264 - core 128 - H.264/MPEG-4 AVC codec - Copyleft
 2003-2012 - http://www.videolan.org/x264.html - options: cabac=1 ref=3
 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00
 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0
 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=3
 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=2 keyint=250 keyint_min=25
 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=23.0
 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
 Output #0, mp4, to 'dejavu_2997.mp4':
   Metadata:
     major_brand     : qt
     minor_version   : 537199360
     compatible_brands: qt
     encoder         : Lavf54.59.106
     Stream #0:0(eng): Video: h264 ([33][0][0][0] / 0x0021), yuv420p,
 1280x720, q=-1--1, 11988 tbn, 29.97 tbc
     Metadata:
       creation_time   : 2013-06-10 21:10:02
       handler_name    : Apple Alias Data Handler
     Stream #0:1(eng): Audio: aac ([64][0][0][0] / 0x0040), 48000 Hz,
 stereo, s16, 139 kb/s
     Metadata:
       creation_time   : 2013-06-10 21:10:02
       handler_name    : Apple Alias Data Handler
 Stream mapping:
   Stream #0:1 -> #0:0 (h264 -> libx264)
   Stream #0:0 -> #0:1 (pcm_s16le -> libfdk_aac)
 Press [q] to stop, [?] for help
 Truncating packet of size 48235 to 21094kB time=00:00:10.45
 bitrate=1327.0kbits/s dup=0 drop=305
 [h264 @ 0x1d32f340] AVC: nal size 7357
     Last message repeated 1 times
 [h264 @ 0x1d32f340] concealing 2250 DC, 2250 AC, 2250 MV errors in P frame
 frame=  314 fps= 19 q=-1.0 Lsize=    2206kB time=00:00:10.51
 bitrate=1718.6kbits/s dup=0 drop=308
 video:2014kB audio:180kB subtitle:0 global headers:0kB muxing overhead
 0.563787%
 [libx264 @ 0x1cc905e0] frame I:3     Avg QP:22.44  size: 52646
 [libx264 @ 0x1cc905e0] frame P:95    Avg QP:24.12  size: 13286
 [libx264 @ 0x1cc905e0] frame B:216   Avg QP:26.36  size:  2970
 [libx264 @ 0x1cc905e0] consecutive B-frames:  7.0%  1.3%  7.6% 84.1%
 [libx264 @ 0x1cc905e0] mb I  I16..4: 26.8% 46.5% 26.7%
 [libx264 @ 0x1cc905e0] mb P  I16..4:  4.9%  7.4%  1.2%  P16..4: 45.3%
 8.6%  5.8%  0.0%  0.0%    skip:26.7%
 [libx264 @ 0x1cc905e0] mb B  I16..4:  0.1%  0.1%  0.0%  B16..8: 34.6%
 1.6%  0.2%  direct: 1.4%  skip:62.0%  L0:47.3% L1:49.4% BI: 3.3%
 [libx264 @ 0x1cc905e0] 8x8 transform intra:52.9% inter:84.7%
 [libx264 @ 0x1cc905e0] coded y,uvDC,uvAC intra: 43.8% 51.0% 13.3% inter:
 9.3% 23.1% 0.4%
 [libx264 @ 0x1cc905e0] i16 v,h,dc,p: 32% 28% 10% 30%
 [libx264 @ 0x1cc905e0] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 18% 14% 29% 18%  4%
 4%  3%  4%  6%
 [libx264 @ 0x1cc905e0] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 25% 22% 19% 11%  5%
 6%  4%  4%  4%
 [libx264 @ 0x1cc905e0] i8c dc,h,v,p: 54% 21% 22%  3%
 [libx264 @ 0x1cc905e0] Weighted P-Frames: Y:1.1% UV:1.1%
 [libx264 @ 0x1cc905e0] ref P L0: 51.4% 10.5% 28.7%  9.4%  0.0%
 [libx264 @ 0x1cc905e0] ref B L0: 68.8% 21.5%  9.8%
 [libx264 @ 0x1cc905e0] ref B L1: 83.7% 16.3%
 [libx264 @ 0x1cc905e0] kb/s:1574.27

 }}}

 Following transcode does not have this lip sync issue:
 {{{
 ffmpeg -i dejavu_20mb.mp4  dejavu_5994.mp4
 ffmpeg version 1.1 Copyright (c) 2000-2013 the FFmpeg developers
   built on May 27 2013 10:30:08 with gcc 3.4.6 (GCC) 20060404 (Red Hat
 3.4.6-9)
   configuration: --enable-gpl --enable-version3 --enable-zlib --enable-
 bzlib --enable-pthreads --enable-libvorbis --enable-libtheora --enable-
 libspeex --enable-libmp3lame --enable-libxvid --enable-libx264 --enable-
 libopencore_amrwb --enable-libopencore_amrnb --enable-libfdk_aac --enable-
 libvpx --enable-libgsm --extra-libs=-static --enable-nonfree --enable-
 libfreetype
   libavutil      52. 13.100 / 52. 13.100
   libavcodec     54. 86.100 / 54. 86.100
   libavformat    54. 59.106 / 54. 59.106
   libavdevice    54.  3.102 / 54.  3.102
   libavfilter     3. 32.100 /  3. 32.100
   libswscale      2.  1.103 /  2.  1.103
   libswresample   0. 17.102 /  0. 17.102
   libpostproc    52.  2.100 / 52.  2.100
 Guessed Channel Layout for  Input Stream #0.0 : stereo
 Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'dejavu_20mb.mp4':
   Metadata:
     major_brand     : qt
     minor_version   : 537199360
     compatible_brands: qt
     creation_time   : 2013-06-10 21:03:17
   Duration: 00:02:41.34, start: 0.000000, bitrate: 1039 kb/s
     Stream #0:0(eng): Audio: pcm_s16le (sowt / 0x74776F73), 48000 Hz,
 stereo, s16, 1536 kb/s
     Metadata:
       creation_time   : 2013-06-10 21:10:02
       handler_name    : Apple Alias Data Handler
     Stream #0:1(eng): Video: h264 (Main) (avc1 / 0x31637661), yuv420p,
 1280x720, 8684 kb/s, 59.94 fps, 59.94 tbr, 5994 tbn, 11988 tbc
     Metadata:
       creation_time   : 2013-06-10 21:10:02
       handler_name    : Apple Alias Data Handler
 [libx264 @ 0x894d3c0] using cpu capabilities: MMX2 SSE2Fast SSSE3
 FastShuffle SSE4.1 Cache64
 [libx264 @ 0x894d3c0] profile High, level 3.2
 [libx264 @ 0x894d3c0] 264 - core 128 - H.264/MPEG-4 AVC codec - Copyleft
 2003-2012 - http://www.videolan.org/x264.html - options: cabac=1 ref=3
 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00
 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0
 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=3
 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=2 keyint=250 keyint_min=25
 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=23.0
 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
 Output #0, mp4, to 'dejavu_5994.mp4':
   Metadata:
     major_brand     : qt
     minor_version   : 537199360
     compatible_brands: qt
     encoder         : Lavf54.59.106
     Stream #0:0(eng): Video: h264 ([33][0][0][0] / 0x0021), yuv420p,
 1280x720, q=-1--1, 11988 tbn, 59.94 tbc
     Metadata:
       creation_time   : 2013-06-10 21:10:02
       handler_name    : Apple Alias Data Handler
     Stream #0:1(eng): Audio: aac ([64][0][0][0] / 0x0040), 48000 Hz,
 stereo, s16, 139 kb/s
     Metadata:
       creation_time   : 2013-06-10 21:10:02
       handler_name    : Apple Alias Data Handler
 Stream mapping:
   Stream #0:1 -> #0:0 (h264 -> libx264)
   Stream #0:0 -> #0:1 (pcm_s16le -> libfdk_aac)
 Press [q] to stop, [?] for help
 Truncating packet of size 48235 to 21094kB time=00:00:10.45
 bitrate=1628.7kbits/s
 [h264 @ 0x8fec440] AVC: nal size 7357
     Last message repeated 1 times
 [h264 @ 0x8fec440] concealing 2250 DC, 2250 AC, 2250 MV errors in P frame
 frame=  623 fps= 24 q=-1.0 Lsize=    2498kB time=00:00:10.51
 bitrate=1945.9kbits/s dup=1 drop=0
 video:2301kB audio:180kB subtitle:0 global headers:0kB muxing overhead
 0.696050%
 [libx264 @ 0x894d3c0] frame I:5     Avg QP:23.28  size: 39919
 [libx264 @ 0x894d3c0] frame P:180   Avg QP:25.53  size:  8264
 [libx264 @ 0x894d3c0] frame B:438   Avg QP:28.27  size:  1526
 [libx264 @ 0x894d3c0] consecutive B-frames:  5.8%  1.0%  1.4% 91.8%
 [libx264 @ 0x894d3c0] mb I  I16..4: 28.0% 54.2% 17.8%
 [libx264 @ 0x894d3c0] mb P  I16..4:  3.3%  3.7%  0.6%  P16..4: 40.9%  5.7%
 3.7%  0.0%  0.0%    skip:42.1%
 [libx264 @ 0x894d3c0] mb B  I16..4:  0.1%  0.0%  0.0%  B16..8: 27.4%  0.5%
 0.1%  direct: 0.3%  skip:71.6%  L0:43.7% L1:54.7% BI: 1.5%
 [libx264 @ 0x894d3c0] 8x8 transform intra:49.9% inter:86.0%
 [libx264 @ 0x894d3c0] coded y,uvDC,uvAC intra: 39.5% 51.3% 12.0% inter:
 4.9% 13.7% 0.1%
 [libx264 @ 0x894d3c0] i16 v,h,dc,p: 30% 31% 13% 26%
 [libx264 @ 0x894d3c0] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 18% 14% 32% 17%  3%
 3%  3%  4%  6%
 [libx264 @ 0x894d3c0] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 27% 24% 19%  9%  5%
 5%  4%  4%  3%
 [libx264 @ 0x894d3c0] i8c dc,h,v,p: 57% 21% 21%  2%
 [libx264 @ 0x894d3c0] Weighted P-Frames: Y:0.6% UV:0.6%
 [libx264 @ 0x894d3c0] ref P L0: 52.0% 10.6% 29.1%  8.4%  0.0%
 [libx264 @ 0x894d3c0] ref B L0: 65.4% 22.8% 11.8%
 [libx264 @ 0x894d3c0] ref B L1: 81.0% 19.0%
 [libx264 @ 0x894d3c0] kb/s:1812.97
 }}}

-- 
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/2696>
FFmpeg <http://ffmpeg.org>
FFmpeg issue tracker


More information about the FFmpeg-trac mailing list