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#152 DirectShowSource bug

v2.5x
closed-remind
Ian Brabham
Filters (75)
5
2005-11-21
2005-07-23
Wilbert Dijkhof
No

This happens with asf files. I haven't notice it with
other formats.

http://forum.doom9.org/showthread.php?p=681676#post681676

and post after that. Apperently disabling the audio (in
dss) influences the encoded video.

Discussion

1 2 > >> (Page 1 of 2)
  • Ian Brabham
    Ian Brabham
    2005-09-25

    • labels: --> Filters
    • milestone: --> v2.5x
    • assigned_to: nobody --> ianb1957
     
  • Ian Brabham
    Ian Brabham
    2005-09-25

    Logged In: YES
    user_id=673887

    Does this still happen with the latest RC1 release?

    Does the new seekzero=true option help?

    I tried the sample clip and with seekzero=true it seems to
    work correctly. This clip also has problems seeking in
    Graphedit. Using EnsureVBRMP3Sync() seems to also help
    a lot.

    IanB

     
  • Logged In: YES
    user_id=591008

    I have to test some more. I can't replicate it anymore in
    RC1 (for some reason i don't understand). But now i don't
    hear audio in my encoding. I will also try some other
    sources and report back.

     
  • Logged In: YES
    user_id=591008

    IanB,

    I think it happens with all clips. I tried one with XviD+MP3
    too. There's an audio, but it's not hearable.

     
  • Ian Brabham
    Ian Brabham
    2005-10-04

    • priority: 5 --> 7
     
  • Ian Brabham
    Ian Brabham
    2005-10-04

    Logged In: YES
    user_id=673887

    When you say "not hearable" do you mean :-
    1. There is an audio track but it is all zero samples.
    or
    2. There is no audio track.

    Also for the record can you please explicitly restate exactly
    what the problem currently is in 2.5.6-rc1.

    KevinM's original problem appears to be "not using" or "option
    not yet available" convertfps. iuVCR definitly produces
    Variable Frame Rate ASF so he must use that option.

    Note :- DSS's convertfps option only applies to the video
    stream. If the audio stream is not contiguous, valid but very
    unusual, DSS cannot decode it correctly. Any silence gaps
    will be omitted and sync will be lost.

    IanB

     
  • Logged In: YES
    user_id=591008

    I zipped the source, script and mpeg-2:
    http://www.geocities.com/wilbertdijkhof/Kevinm.zip
    I also included the sound which is present in the asf
    stream: vdub.wav

    It has an audio track, but i'm not sure whether it has zero
    samples. If you can't play mpeg-2 files, i can demux the
    audio for you.

    ----------

    About the original problem. The original problem (with avs
    v2.56b4 and older versions) was that _only_ when encoding to
    mpeg-2, the number of frames got doubled. This happened with
    TMPGEnc and QuEnc. However, when disabling the audio
    DSS(audio=false), the number of frames was correct.

    "Also for the record can you please explicitly restate exactly
    what the problem currently is in 2.5.6-rc1."

    The length of the video is fine, and it has audio, but it is
    not hearable (i'm not sure whether this means it has no
    samples). Anyway, you can check it yourself: short2-tmpgenc.mpg.

    I hope the provided info is sufficient to solve the mystery :)

     
  • Ian Brabham
    Ian Brabham
    2005-10-05

    Logged In: YES
    user_id=673887

    Okay, this is the original short_lowres2.asf file I already had.
    It is an A_S_F format file with all the bad baggage that
    entails. The clip is 45 frames, 1.8 seconds. Being ASF like
    all ASF files you cannot reliably seek using the interface we
    use. This is why I added the seekzero option, it helps but it is
    not perfect. Both TMPEnc and GraphEdit exhibit all the same
    difficulties that AVS experiences. With ASF files you must
    aim to parse the streams exactly once.

    With such short streams TMPEnc seems to have a problem
    loosing the end of the audio stream independant of the input
    source. I tried encoding an AVS clip using BlankClip() and
    Tone() the same length as your clip and a true AVI copy of
    the same streams and all showed the same problem.
    Padding the streams to a reasonable length allows all the
    original source material to be processed (some of the audio
    padding gets lost).

    Your mpeg2 file has an audio stream which is short (as
    expected and is the expected length) but all the samples are
    zero (silence), this I do not understand and cannot reproduce.
    Can you try using the new seekzero=true option and padding
    the streams with a "Last+BlankClip(Last)" at the end of the
    script and report your findings.

    I think all the problems here are related to the restrictions in
    the unlicenced DirectShow ASF interface we use. Seeking
    with ASF is just not reliable and we have to live within this.

    IanB

     
  • Logged In: YES
    user_id=591008

    Did several tests:

    [code]
    DirectShowSource("F:\TestStreams\Temp\Kevinm\short_lowres2.asf",
    fps=25, convertfps=true, seekzero=true)
    ConvertToRGB24()
    [/code]
    Resulting mpeg-2 has sound, but samples are zero (not
    hearable). Length is correct. Happens also when selecting
    mpeg-1.

    [code]
    DirectShowSource("F:\TestStreams\Temp\Kevinm\short_lowres2.asf",
    fps=25, convertfps=true, seekzero=true)
    ConvertToRGB24()
    last+last.blankclip
    [/code]
    Resulting mpeg-2 has sound, but samples are zero (not
    hearable). Length is correct.

    [code]
    # XviD+MP3; 4911 frames.
    DirectShowSource("F:\TestStreams\Temp\Kevinm\holly_valance-down_boy(topofthepops_xvid).avi",
    fps=25, convertfps=true, seekzero=true)
    ConvertToRGB24()
    [/code]
    Resulting mpeg-2 has sound, but samples are zero (not
    hearable). Length is correct.

    [code]
    DirectShowSource("F:\TestStreams\Temp\Kevinm\short_lowres2.asf",
    fps=25, convertfps=true, seekzero=true)
    ConvertToRGB24()
    [/code]
    Encoded to XviD+MP3 in VDubMod. Resulting avi has sound, and
    is hearable. Length is correct.

    So, it also happens with other formats (avi ~ 5000 frames)).

    Could you send me some source for which you are sure the
    encoded (to mpeg-2) sound is correct, along with the used
    dss.dll?

     
  • Ian Brabham
    Ian Brabham
    2005-10-06

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    user_id=673887

    I'll stick up a .zip tomorrow.

    Do these scripts encode correctly

    ColorBars()
    AssumeFPS(25, false)
    Trim(0, 44)
    ConvertToRGB24()

    DirectShowSource
    ("F:\TestStreams\Temp\Kevinm\short_lowres2.asf",
    fps=25, convertfps=true, seekzero=true)
    ConvertToRGB24()
    Amplify(0.99)

    IanB

     
1 2 > >> (Page 1 of 2)