Audio Normalize method in audio options

  • Dorin Cristescu

    Dorin Cristescu - 2009-02-26


    I need sometimes the Normalize feature on my media files.
    I would like to know if the actual method of normalizing introduces any distorsions.

    I.E. I want to know if the method is the one by definition: Find out the maximum intensity point of the clip, then proportionally increase the whole waveform so that that maximum intensity moment is at 100% audio power or 0dB whichever you prefer.

    I ask because by definition this would imply a pass through the whole media file for finding out the maximum value, and then only playback at a consecutive pass should have the correct gain on the waveform.

    However I notice that the method also works for streaming media, which means that the gain happens at the first pass through the media, which means that the gain value is some other way computed, which could incurr a past 100% gain at top moments in the clip, producing distorsions.

    Thanks for clearing this up,

    • Gabest

      Gabest - 2009-02-26

      It just extends min/max as it advances, when it gets louder it automatically makes that the new max, and there is a limit at the lower end to not amplify noise too much.

      • Dorin Cristescu

        Dorin Cristescu - 2009-02-26

        Thanks for the authoritative and prompt answer.

        No offense, but IMHO then the name is probably misleading.
        Public definitions (including wikipedia - in a flawed page but nevertheless) explain "Normalizing" the way I did opening this thread.

        To be completely accurate perhaps some other name should be chosen (e.g. "Adaptive normalizing" or such).
        From what I've seen around plenty of media players make this function their bitch, but MPC is currently the fairest and best, so IT shouldn't. Perhaps this feature or name should be improved (I would love to see Normalizing per se implemented the way I explained at the beginning, possibly with the mention that it works for offline clips only and alternatively chosing the existing "Adaptive normalizing" for streaming via a radio button).
        (Also there are efforts to standardize this function at rip time - with additional tags in the clip, so perhaps attention should be payed to this also - I think it's called MP3Gain)



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