After some research, it looks that both methods 1 and 2 of mplayer volnorm are "dynamic" normalisation. And not peak method.
Usually, for films, the best is to use a peak method. What Mplayer doesn't seem able to do.
Peak method is : the audio track volume is adjusted so the peak(s) is set to the digital maximum, this gives a ratio which is applyed to the full track. (method is 2 pass, usually).
That's perfect for a film which is a professional soundtrack normalized to fit it's mean volume to a pleasant volume, so that it's peak is not systematically at the digital maximum.
Other methods like the two implemented by mplayer are well for cheap playback material or TV playback. Definitly perfect for some contents, but not DVD films.
I think OggEnc could give the choice between :
- no normalization (ALREADY IMP)
- peak level normalization (NEW)
- dynamic normalization (and there are also several methods) (ALREADY IMP)
Last edit: Sandburg 2013-09-03
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I would like to know what kind of algorithm is used beneath the "normalisation" check box ?
Is it as I expected, a constant multiplicator to fit the best peak to 0db ? Or a dynamic normalisation (several exist) ?
Last edit: Sandburg 2013-08-13
The normalisation used is the volnorm audio filter of mplayer with method 1.
Thank you.
After some research, it looks that both methods 1 and 2 of mplayer volnorm are "dynamic" normalisation. And not peak method.
Usually, for films, the best is to use a peak method. What Mplayer doesn't seem able to do.
Peak method is : the audio track volume is adjusted so the peak(s) is set to the digital maximum, this gives a ratio which is applyed to the full track. (method is 2 pass, usually).
That's perfect for a film which is a professional soundtrack normalized to fit it's mean volume to a pleasant volume, so that it's peak is not systematically at the digital maximum.
Other methods like the two implemented by mplayer are well for cheap playback material or TV playback. Definitly perfect for some contents, but not DVD films.
I think OggEnc could give the choice between :
- no normalization (ALREADY IMP)
- peak level normalization (NEW)
- dynamic normalization (and there are also several methods) (ALREADY IMP)
Last edit: Sandburg 2013-09-03