DV recording problem

Discussion in 'Professional Video Production' started by RickMerrill, Mar 4, 2009.

  1. RickMerrill

    RickMerrill Guest

    Recorded DV25 files in 5.1 mode (mistakenly) so the
    frame rate was reduced and the results are horrific.

    I need to replay the DV25 files back to the camera
    OR find some software that will convert them. Any
    suggestions?
     
    RickMerrill, Mar 4, 2009
    #1
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  2. RickMerrill

    ushere Guest

    please explain? you captured how? 5.1 is audio. 5:1 is default
    compression for dv.....
     
    ushere, Mar 4, 2009
    #2
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  3. RickMerrill

    RickMerrill Guest

    Correct: 5.1 audio when it should have been simple 2channel.

    The result was to lower the frame rate over 1394 so the sound
    is like Mickey Mouse on adrenaline.

    Now I need to convert 5.1 to 2-channel audio yet keep it in sync with
    the video.

    I suppose I can play it back-into the camercorder-tape, then play that
    back as 2-channel!
     
    RickMerrill, Mar 4, 2009
    #3
  4. RickMerrill

    mkujbida Guest



    There's no reason (that I can think of) why capturing 5.1 would affect
    your frame rate.
    What camcorder did these files come from and what NLE are you using?

    Mike
     
    mkujbida, Mar 4, 2009
    #4
  5. Is the frame rate really reduced or is your playback system having problems
    with only the audio decode?

    You may want to post a chunk of one of the files somewhere for us to see.

    I guess the tapes are gone? If you have some frame dropouts recordign back
    to the caemra won't do much for ya.
     
    Flatulent Father Flannigan, Mar 4, 2009
    #5
  6. The DV format does not support "5.1 audio" that I've ever heard of.
    Do you have any kind of reference for this? The only alternate audio
    mode for DV that I've seen in the 4-channel one (4 channels @ 12-
    bit vs. the "normal" 2-channels @ 16-bit). The 12-bit resolution is
    so lousy that nobody uses this mode (except accidentlly, after which
    they complain bitterly about it.)
    It is actually *out of sync* now? Or is it in-sync, but at the wrong
    pitch (or whatever)?
    What equipment was it originally recorded on?
    What equipment and software was it captured with?
     
    Richard Crowley, Mar 4, 2009
    #6
  7. May have been 32Khz audio eh?
     
    Flatulent Father Flannigan, Mar 4, 2009
    #7
  8. RickMerrill

    RickMerrill Guest


    I have been told that the 4-channel reduces the audio to 32khz
    and I need 48khz - so I am Guessing that 5.1 had a similar effect.
    [I should not have called it a 'frame rate' change but an audio encodign
    reduction.]

    What can I find that will let me recover the data?
     
    RickMerrill, Mar 4, 2009
    #8
  9. "RickMerrill" wrote ...
    You need to provide us (me, at least) with some reference for "5.1
    audio" on DV before I will even believe this is what you have.
    Asking again: What equipment was it recorded on?
    What equipment and software was it captured with?
    Can you play back the original tape on the original equipment?
    Are the sound tracks reproduced correctly when you do that?
    Barring that, that you may have a sticky problem on your hands.

    I strongly suspect that the tape was recorded in 4-channel (12-bit,
    32KHz sample rate) mode, and then improperly captured in 2-
    channel, 16-bit, 48KHz sample rate mode. Proper equipment
    and/or software should not have even allowed this capture to
    happen in the first place, so you are starting with an unknown,
    undefined, bastard data stream. Hence the only known good
    solution is to play back the original tape on the original equipment
    and get the capture right in the first place.

    And I still don't believe there is any such thing as "5.1 audio"
    possible in DV recording. Unless you're talking about some
    sort of encoded, matrixed, add-on scheme like this....
    http://www.holophone.com/home.html
     
    Richard Crowley, Mar 4, 2009
    #9
  10. RickMerrill

    RickMerrill Guest

    Parse this:
    Mic: ECM-HW1R bluetooth set to 5.1ch CENTER ==>
    Camcorder: Sony HDR-HC1 4:3 1394 ==>
    Tapeless: FireStore FS4 recording DV Raw.
    If you "paguntas" the above, you will see there was No Tape.
    I'm about to try that.
    Don't I know it!

    All the evidence is that you are correct in this.
    That's what Sony calls it. See above.
     
    RickMerrill, Mar 5, 2009
    #10
  11. The listed camera appears to have ordinary 2-channel ("stereo")
    audio recording and playback functionality. No "5.1" in evidence.

    DV-25 does not support "5.1" audio. Never did. Never will.

    "5.1" appears to be a marketing gimmick for your Bluetooth mic.

    You appear to have a compatibility or operational problem between
    your (monaural) Bluetooth microphone and your camera.

    Suggest using a conventional microphone (the built-in mic or some
    regular plug-in mic) and see if you can record and playback sound
    properly.

    Did the camera record any of the troublesome footage? Does the
    audio play back on the camera properly?
     
    Richard Crowley, Mar 5, 2009
    #11
  12. RickMerrill

    RickMerrill Guest

    I can buy that. But I'm told that DV-25 does support 4-channel at lower
    than needed encoding rate.
    Only with this particular setting.
    Have done that many times - forgot to check the setting on the bluetooth
    this time.
    Actually it did! I've just played it back and re-recorded it - we'll see!
     
    RickMerrill, Mar 5, 2009
    #12
  13. "RickMerrill" wrote ...
    DV supports two audio modes:
    2-channel, 16-bit, 48K sample rate
    4-channel, 12-bit, 32K sample rate
    http://en.wikipedia.org/wiki/Dv#Audio

    But it is the 12-bit resolution more than the 32K sample rate that
    makes the audio performance sub-par to most peoples' ears.

    Because of the poor quality of the 4-channel mode, there is little
    support for the mode. Nobody has ever come to these newsgroups
    saying how pleased they were with the 4-channel performance.
     
    Richard Crowley, Mar 5, 2009
    #13
  14. RickMerrill

    RickMerrill Guest

    I did my 1st ever recording at 12-bit and the result was total silence
    from the playout video server! Well, 2^12/2^16 is pretty low!

    Apparently the Mickey mouse is because the 5.1-ch was downgraded to 4-ch
    and the 32khz gets played back at 48khz - ta da!

    I'll try playback without 1394!
     
    RickMerrill, Mar 5, 2009
    #14
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