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slhck / ffmpeg-normalize

Audio Normalization for Python/ffmpeg
MIT License
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Report A weighted loudness #134

Open rpx91 opened 4 years ago

rpx91 commented 4 years ago

Hi again,

Would it be possible to report the A weighting for loudness in addition to the K weighting/LUFS standard?

I understand that the LUFS/K weighting is much better for normalizing loudness. However, I am interested in hearing loss prevention and the A weighting scale is used. Currently the heavy bass tracks in most movies are outputting high LUFS values, but I believe that's not representative on the impact to your ears.

Here are some comparisons of the curves: https://www.mathworks.com/help/audio/ref/weightingfilter-system-object.html

Thank you kindly :)

slhck commented 4 years ago

Thanks for the suggestion. In principle it would be nice to have this, and I understand your reasoning, but:

  1. The ITU-R BS.1770-4 standard specifies K-weighting to be used for the loudness normalization that is used in EBU R128.
  2. The loudnorm filter in FFmpeg only supports this weighting.
  3. This Python project uses the FFmpeg filter, so any modifications would have to be done upstream.

So, this request might be better suited for https://trac.ffmpeg.org/ as a feature request for the loudnorm filter.