Python 读取WAV文件并绘制波形图

aa

Python 读取WAV文件并绘制波形图

ffmpeg -i test_pcm_mulaw.wav  -f wav -codec:a pcm_s16le -ar 8000 -ac 1 out.wav

yingc@yingc:~/media/audio$ ffprobe out.wav
ffprobe version 2.2.4 Copyright (c) 2007-2014 the FFmpeg developers
built on Apr 13 2016 08:42:24 with gcc 4.6 (Ubuntu/Linaro 4.6.3-1ubuntu5)
configuration: --prefix=/home/yingc/git/thirdparty/av/ffmpeg/output/ffmpeg_build/ --bindir=/home/yingc/git/thirdparty/av/ffmpeg/output/bin --extra-cflags=' -I/home/yingc/git/thirdparty/av/ffmpeg/output/ffmpeg_build/include' --extra-ldflags=-L/home/yingc/git/thirdparty/av/ffmpeg/output/ffmpeg_build/lib --extra-libs=-ldl --enable-gpl --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-nonfree --enable-x11grab --disable-stripping --enable-extra-warnings --disable-optimizations --enable-openssl --enable-static --enable-debug=3
libavutil 52. 66.100 / 52. 66.100
libavcodec 55. 52.102 / 55. 52.102
libavformat 55. 33.100 / 55. 33.100
libavdevice 55. 10.100 / 55. 10.100
libavfilter 4. 2.100 / 4. 2.100
libswscale 2. 5.102 / 2. 5.102
libswresample 0. 18.100 / 0. 18.100
libpostproc 52. 3.100 / 52. 3.100
Input #0, wav, from 'out.wav':
Metadata:
encoder : Lavf55.33.100
Duration: 00:08:10.03, bitrate: 128 kb/s
Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 8000 Hz, 1 channels, s16, 128 kb/s

　　

Opening a wave file in python: unknown format: 49. What's going wrong?

aa