Question

Users upload WAV files to my service. I need to programmatically know the bit rate and sample rate of the WAV files.

How would I do this? Preferably on Windows, though a Unix tool would be fine too. A command line tool would be handy.

Answer 1

See MediaInfo. This tool provides Graphical user interface, command line interface, and library (.dll/.so/.dylib). I prefer using library.

If you wanna try CLI, here’s a command line example.

MediaInfo.exe "--Inform=Audio;" --Output=XML "test.wav" --logfile=result.xml

Then I got a result.xml.

<?xml version="1.0" encoding="UTF-8"?>
<Mediainfo version="0.7.61">
<File>
<track type="General">
<Complete_name>test.wav</Complete_name>
<Format>Wave</Format>
<File_size>14.2 KiB</File_size>
<Duration>659ms</Duration>
<Overall_bit_rate>177 Kbps</Overall_bit_rate>
</track>

<track type="Audio">
<ID>0</ID>
<Format>PCM</Format>
<Format_settings__Endianness>Little</Format_settings__Endianness>
<Codec_ID>1</Codec_ID>
<Duration>659ms</Duration>
<Bit_rate>176.4 Kbps</Bit_rate>
<Channel_s_>1 channel</Channel_s_>
<Sampling_rate>22.05 KHz</Sampling_rate>
<Bit_depth>8 bits</Bit_depth>
<Stream_size>14.2 KiB (100%)</Stream_size>
</track>

</File>
</Mediainfo>

Just parse this file and find the string <Sampling_rate>22.05 KHz</Sampling_rate>.