How to read Bit rate of .wav file in C#

Question

given that I have a .wav file, what would be best way to read its Bit rate property in C#. I have tried Shell, and asked a question Is "Bit rate" property fixed i

Answer 1

With NAudio, the bitrate is calculated via the AverageBytesPerSecond member of the WaveFormat structure:

using (var reader = new WaveFileReader(filename))
{
    bitrate = reader.WaveFormat.AverageBytesPerSecond * 8;
}

This will work for all uncompressed audio formats and most compressed. The WAV file format is a container format and can actually contain audio in any codec, even though it's most common use is PCM. But not all codecs are CBR (constant bit rate). Some have a variable bit rate, so the AverageBytesPerSecond property may be an estimate.

Answer 2

You can easily read the value at offset 28 in the file.

int bitrate;
using (var f = File.OpenRead(filename))
{
    f.Seek(28, SeekOrigin.Begin);
    byte[] val = new byte[4];
    f.Read(val, 0, 4);
    bitrate = BitConverter.ToInt32(val, 0);
}

That should work for uncompressed WAV files (the most common type). See https://ccrma.stanford.edu/courses/422/projects/WaveFormat/.