将立体声文件转换为单声道但保留峰值和 RMS 响度

Question

我正在使用 ffmpeg 将立体声音频文件转换为单声道。

ffmpeg -i  -ac 1 -ab 192k mono_

但是，转换后，RMS 和峰值响度级别不一样。

Tests-iMac:auditions test$ ./rms.sh mono_test.mp3 
 mean_volume: -20.1 dB
 max_volume: -0.2 dB
 Peak level dB: -0.150201
 RMS level dB: -20.138039
 RMS peak dB: -10.650649
 RMS trough dB: -94.923318
 Flat factor: 0.000000
 Peak count: 2.000000
 Bit depth: 32/32
 Number of samples: 5800320
 Number of NaNs: 0.000000
 Number of Infs: 0.000000
 Number of denormals: 0.000000
Tests-iMac:auditions test$ ./rms.sh test.mp3 
 mean_volume: -22.9 dB
 max_volume: -2.9 dB
 Peak level dB: -2.896314
 RMS level dB: -22.883812
 RMS peak dB: -13.397327
 RMS trough dB: -95.943631
 Flat factor: 0.000000
 Peak count: 2.000000
 Bit depth: 32/32
 Number of samples: 5800320
 Number of NaNs: 0.000000
 Number of Infs: 0.000000
 Number of denormals: 0.000000

第一个输出是单声道文件，它在技术上比立体声文件更响亮，排在第二位。如何在转换为单声道的同时保留峰值和 RMS 值？为了获得要传递给单声道转换过程的立体声响度值，我编写脚本没有问题。

谢谢！

Answer 1

我只需要使用音频过滤器将音量降低 2.7db。

ffmpeg -i  -ac 1 -af "volume=-2.7dB" -ab 192k mono_

将立体声文件转换为单声道但保留峰值和 RMS 响度

Converting stereo file to mono but preserving peak and RMS loudness

ffmpeg

data-conversion