[FFmpeg-devel] [PATCH] Improved AC3 decoder level support (heavy drc, dialnorm)

Jean-Francois Thibert jfthibert at google.com
Wed Aug 27 03:35:53 CEST 2014

On Tue, Aug 26, 2014 at 7:40 PM, Michael Niedermayer <michaelni at gmx.at> wrote:
> do you have a testcase/sample to test this ?
I don't have any specific sample but this can be tested with any
broadcast or most disc source using AC3 audio. I just tried with the
Broadway-5.1 clip from samples.mplayerhq.hu/A-codecs/AC3 and it
contains both types of DRC and can be decoded in multiple modes

./ffmpeg -heavy_compr 1 -target_level -20 -i Broadway-5.1.ac3 -acodec
pcm_s16le -ac 2 BroadwayHeavyDRC.wav

./ffmpeg -drc_scale 1 -target_level -31 -i Broadway-5.1.ac3 -acodec
pcm_s16le -ac 2 BroadwayLightDRC.wav

./ffmpeg -drc_scale 0 -target_level -31 -i Broadway-5.1.ac3 -acodec
pcm_s16le -ac 2 BroadwayNoDRC.wav

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