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  1. I have a 3 hour .ts file with little skips in the audio every minute of the broadcast. Is there a way to remove the skips using ffmpeg? And without causing an audio sync issue.

    Thanks


    I don't know if this matters, but the skipping comes from the original broadcast. It is not the fault of the recording or recording device.
    Last edited by mtepper27; 23rd Jul 2018 at 14:52.
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    What does "skip" mean ?
    Do you mean that when you listen the audio drops out and then resumes with sync intact?
    That means the audio is missing for those parts.

    FFmpeg? I think you should be using an Audio Editor such as Audacity
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  3. Yes, the audio drops out on the ABC feed for a second in many parts of the recording. So since the audio is not there, I assume there is no way to fix it.. What can I do with Audacity?

    And thank you for responding.
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    Originally Posted by mtepper27 View Post
    Yes, the audio drops out on the ABC feed for a second in many parts of the recording. So since the audio is not there, I assume there is no way to fix it.. What can I do with Audacity?

    And thank you for responding.
    If your skipping parts is just silence, don't need to worry too much about that, since you can't "fix" it.
    In your case the audio editor probably wont be able to help you, but in general,
    it can change volume levels, do noise reduction, treble/bass equalization, slow down/speed up, pitch change, etc,etc. and
    a whole lot more if/when you need it.
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  5. Originally Posted by mtepper27 View Post
    Yes, the audio drops out on the ABC feed for a second in many parts of the recording. So since the audio is not there, I assume there is no way to fix it.. What can I do with Audacity?

    And thank you for responding.
    Hm,

    does this mean that your audio has gaps or is there simply silence?

    The gap-thing can become annoying if you e.g. try to create a VP9/Opus dash stream as it will cause Shaka Player to fail.

    I've had that problem and the solution has been to fill the gaps with silence. That can be done with ffmpeg and the following audio filter:
    -af aresample=async=1:first_pts=0
    Last edited by fornit; 23rd Jul 2018 at 17:42.
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  6. The ability to fix this depends a LOT on not only how long the gap is, but what the surrounding audio is like.

    I use a professional tool called iZotope (it is very expensive, but you can download a free trial). It has a "replace" function in its Spectral Repair module that can sometimes do a miraculous job of filling in a gap. The shorter the gap, the more invisible the fix.

    Another way to fix is to copy/paste audio from other sections of the audio. I first learned to do this back in the early days of Napster when many of the uploaded files were screwed up, either because of incompetence, or by music industry people who tried to inundate Napster with broken audio. Here is a short clip of a song I'd tried to find for decades which showed up on Napster, but with some of the audio missing. It is a cover of what used to be an obscure Beatles song called "Bulldog." This cover was done back in 1971 by the original all-women rock group called Fanny. In this case the "gap" was a needle skip on the record someone got the music from. I was able to insert the missing music from a later chorus where the music was repeated almost exactly. The attached 23 second file starts with the broken version and then after one second of silence, the same track is repeated, but remastered, and with the missing music inserted.

    So, like I said above, the ability to repair these things depends a LOT on the audio and what surrounds it. In this case, the repair was pretty much perfect.
    Image Attached Files
    Last edited by johnmeyer; 23rd Jul 2018 at 18:11. Reason: clarification
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