[FFmpeg-trac] #8406(undetermined:new): Audio and subtitle streams are with incorrect duration when demux UHDs with multi m2ts

FFmpeg trac at avcodec.org
Thu Nov 28 17:46:34 EET 2019

#8406: Audio and subtitle streams are with incorrect duration when demux UHDs with
multi m2ts
             Reporter:  zqslzwzw     |                    Owner:
                 Type:  defect       |                   Status:  new
             Priority:  normal       |                Component:
                                     |  undetermined
              Version:  git-master   |               Resolution:
             Keywords:               |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |

Comment (by zqslzwzw):

 Replying to [comment:1 cehoyos]:
 > Replying to [ticket:8406 zqslzwzw]:
 > > {{{
 > > % ffmpeg -i bluray:..\Toy.Story.4.2019.ULTRAHD.Blu-
 ray.2160p.HEVC.TrueHD.Atmos.7.1-xxx -playlist 4 -map 0:2 -c copy  2.eac3
 -map 0:3 -c copy  3.eac3 -map 0:4 -c copy  4.eac3 -map 0:5 -c copy  5.eac3
 -map 0:6 -c copy  6.eac3 -map 0:7 -c copy  7.eac3 -map 0:8 -c copy  8.eac3
 -map 0:9 -c copy  9.sup -map 0:10 -c copy  10.sup -map 0:11 -c copy
 11.sup -map 0:12 -c copy  12.sup -map 0:13 -c copy  13.sup
 > > }}}
 > > The whole log file is too large (171 MB) to paste, so only the header
 is included as attachment.
 > Why can't you provide the console output of the command line pasted
 > It's hard to believe that it's too big to be shown here.
 > What is your actual use-case and how is extracting raw files supposed to
 make the output file longer (as you claim)?
 I would like to appreciate you for your attention. I will try my best to
 provide useful information further.

 With regard to the first question, indeed the console output of the
 command line I used is very very long, such that it rapidly exceeds the
 length limitation of console screen buffer. I have to redirect this output
 to file (by append '1> stdout.txt 2> stderr.txt' to the command line) to
 see the whole output. So, actually the log file whose size is 171 MB I
 mentioned above is exactly what the console output for the command line I
 used. So I picked the first 2000 lines and the last 2000 lines. If this is
 not sufficient to judge the case, I am glad to pick more or upload it to
 some location at your instruction.

 The second question. I demux this uhd as I would like to use the extracted
 audio and subtitle stream to mux encoded video stream, for my own interest
 other than commercial purpose. So if the duration of the extracted audio
 stream varies from the original value, the mux version will behave
 imperfect as the audio and video are not synchronous.

 When it comes to the last question, I am sorry but I feel that I do not
 quite catch it (English is not my native language). Actually I know litter
 about audio and video. In my opinion, since the duration of audio should
 be equal to the value of the video as they are synchronous in original
 movie, the extracted audio streams should hold the same duration as the
 packaged one.

Ticket URL: <https://trac.ffmpeg.org/ticket/8406#comment:3>
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