＆＃34;体积＆＃34;过滤器在复杂过滤器中不起作用。转换后的音频不会影响音量。
环境：Mac OS 10.12.6
ffmpeg -i /path/bg.mp3 -y -filter_complex [0:0]volume=0[output] -map
[output] -acodec libmp3lame -write_xing 0 /path/mixed.mp3
完整日志============================================= ========================
liqideMacBook-Pro:pinyin-api work$ ffmpeg -i
/Users/work/dev/codebase/pinyin/pinyin-api/test/resources/bg_audio2.mp3
-y -filter_complex [0:0]volume=0.1[output] -map [output] -acodec
libmp3lame -f mp3 -write_xing 0 /Users/work/dev/codebase/pinyin/pinyin-
api/test/resources/mixed3.mp3
ffmpeg version 3.4.1 Copyright (c) 2000-2017 the FFmpeg developers
built with Apple LLVM version 9.0.0 (clang-900.0.39.2)
configuration: --prefix=/usr/local/Cellar/ffmpeg/3.4.1 --enable-
shared --enable-pthreads --enable-version3 --enable-hardcoded-tables --
enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-
gpl --enable-libmp3lame --enable-libx264 --enable-libxvid --enable-
opencl --enable-videotoolbox --disable-lzma
libavutil 55. 78.100 / 55. 78.100
libavcodec 57.107.100 / 57.107.100
libavformat 57. 83.100 / 57. 83.100
libavdevice 57. 10.100 / 57. 10.100
libavfilter 6.107.100 / 6.107.100
libavresample 3. 7. 0 / 3. 7. 0
libswscale 4. 8.100 / 4. 8.100
libswresample 2. 9.100 / 2. 9.100
libpostproc 54. 7.100 / 54. 7.100
Input #0, mp3, from '/Users/work/dev/codebase/pinyin/pinyin-
api/test/resources/bg_audio2.mp3':
Metadata:
title : 喜洋洋
album : 贺岁新年音乐会
encoder : Lavf56.4.101
Duration: 00:02:43.58, start: 0.025057, bitrate: 128 kb/s
Stream #0:0: Audio: mp3, 44100 Hz, stereo, s16p, 128 kb/s
Stream mapping:
Stream #0:0 (mp3) -> volume
volume -> Stream #0:0 (libmp3lame)
Press [q] to stop, [?] for help
Output #0, mp3, to '/Users/work/dev/codebase/pinyin/pinyin-
api/test/resources/mixed3.mp3':
Metadata:
TIT2 : 喜洋洋
TALB : 贺岁新年音乐会
TSSE : Lavf57.83.100
Stream #0:0: Audio: mp3 (libmp3lame), 44100 Hz, stereo, fltp
Metadata:
encoder : Lavc57.107.100 libmp3lame
[libmp3lame @ 0x7fad80001a00] Trying to remove 1152 samples, but the
queue is empty
size= 2556kB time=00:02:43.57 bitrate= 128.0kbits/s speed=51.7x
video:0kB audio:2556kB subtitle:0kB other streams:0kB global
headers:0kB muxing overhead: 0.003782%
liqideMacBook-Pro:pinyin-api work$
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