[FFmpeg-devel] [PATCH 2/3] lavfi/ebur128: add metadata injection. - volnorm.patch (0/1)

[Jan Ehrhardt]

Jan Ehrhardt in gmane.comp.video.ffmpeg.devel (Wed, 01 May 2013 22:10:54
+0200):
>In the test video the first three normalization frames had a loudness
>(I) of -70:
>
>t: 0.0999792  M:-120.7 S:-120.7     I: -70.0 LUFS     LRA:   0.0 LU
>t: 0.199979   M:-120.7 S:-120.7     I: -70.0 LUFS     LRA:   0.0 LU
>t: 0.299979   M:-120.7 S:-120.7     I: -70.0 LUFS     LRA:   0.0 LU
>t: 0.399979   M: -20.7 S:-120.7     I: -20.7 LUFS     LRA:   0.0 LU

Sorry for the double post. Too impatient.
This is what the patched FFmpeg made out of it, after normalizing:

 t: 0.0999792  M:-120.7 S:-120.7     I: -70.0 LUFS     LRA:   0.0 LU
 t: 0.199979   M:-120.7 S:-120.7     I: -70.0 LUFS     LRA:   0.0 LU
 t: 0.299979   M:-120.7 S:-120.7     I: -70.0 LUFS     LRA:   0.0 LU
 t: 0.399979   M: -21.0 S:-120.7     I: -21.0 LUFS     LRA:   0.0 LU
 t: 0.499979   M: -20.5 S:-120.7     I: -20.7 LUFS     LRA:   0.0 LU
 t: 0.599979   M: -19.7 S:-120.7     I: -20.3 LUFS     LRA:   0.0 LU
 t: 0.699979   M: -19.5 S:-120.7     I: -20.1 LUFS     LRA:   0.0 LU
 t: 0.799979   M: -19.0 S:-120.7     I: -19.9 LUFS     LRA:   0.0 LU
 t: 0.899979   M: -18.4 S:-120.7     I: -19.6 LUFS     LRA:   0.0 LU
 t: 0.999979   M: -17.6 S:-120.7     I: -19.3 LUFS     LRA:   0.0 LU
 t: 1.09998    M: -16.3 S:-120.7     I: -18.8 LUFS     LRA:   0.0 LU
 t: 1.19998    M: -15.9 S:-120.7     I: -18.3 LUFS     LRA:   0.0 LU
 t: 1.29998    M: -15.6 S:-120.7     I: -18.0 LUFS     LRA:   0.0 LU
 t: 1.39998    M: -16.4 S:-120.7     I: -17.8 LUFS     LRA:   0.0 LU
 t: 1.49998    M: -17.6 S:-120.7     I: -17.8 LUFS     LRA:   0.0 LU
 t: 1.59998    M: -18.2 S:-120.7     I: -17.8 LUFS     LRA:   0.0 LU
 t: 1.69998    M: -19.5 S:-120.7     I: -17.9 LUFS     LRA:   0.0 LU
 t: 1.79998    M: -19.0 S:-120.7     I: -18.0 LUFS     LRA:   0.0 LU
 t: 1.89998    M: -18.8 S:-120.7     I: -18.0 LUFS     LRA:   0.0 LU
 t: 1.99998    M: -19.7 S:-120.7     I: -18.1 LUFS     LRA:   0.0 LU

In the beginning somewhat unstable (see M), but not too distressing. In
the end (one hour of video later) the I goes down to -22.8, quite close
to the target of -23.

This was before compressing (video) and normalizing (audio):

  Integrated loudness:
    I:         -18.1 LUFS
    Threshold: -28.1 LUFS

  Loudness range:
    LRA:         6.1 LU
    Threshold: -38.1 LUFS
    LRA low:   -21.4 LUFS
    LRA high:  -15.3 LUFS

And afterwards:

  Integrated loudness:
    I:         -22.8 LUFS
    Threshold: -32.8 LUFS

  Loudness range:
    LRA:         6.0 LU
    Threshold: -42.8 LUFS
    LRA low:   -26.0 LUFS
    LRA high:  -20.0 LUFS

This was an untypical video for us. Most videos need a higher volume,
this one's volume was lowered by 4.7 dB.

Jan