scipy.io.wavfile.read

scipy.io.wavfile.read(filename, mmap=False)

Open a WAV file

Return the sample rate (in samples/sec) and data from a WAV file.

Parameters

filenamestring or open file handle

Input wav file.

mmapbool, optional

Whether to read data as memory-mapped. Only to be used on real files (Default: False).

New in version 0.12.0.

Returns

rateint

Sample rate of wav file.

datanumpy array

Data read from wav file. Data-type is determined from the file; see Notes.

Notes

This function cannot read wav files with 24-bit data.

Common data types: [1]

WAV format	Min	Max	NumPy dtype
32-bit floating-point	-1.0	+1.0	float32
32-bit PCM	-2147483648	+2147483647	int32
16-bit PCM	-32768	+32767	int16
8-bit PCM	0	255	uint8

Note that 8-bit PCM is unsigned.

References

1

IBM Corporation and Microsoft Corporation, “Multimedia Programming Interface and Data Specifications 1.0”, section “Data Format of the Samples”, August 1991 http://www.tactilemedia.com/info/MCI_Control_Info.html

Examples

>>> from os.path import dirname, join as pjoin
>>> from scipy.io import wavfile
>>> import scipy.io

Get the filename for an example .wav file from the tests/data directory.

>>> data_dir = pjoin(dirname(scipy.io.__file__), 'tests', 'data')
>>> wav_fname = pjoin(data_dir, 'test-44100Hz-2ch-32bit-float-be.wav')

Load the .wav file contents.

>>> samplerate, data = wavfile.read(wav_fname)
>>> print(f"number of channels = {data.shape[1]}")
number of channels = 2
>>> length = data.shape[0] / samplerate
>>> print(f"length = {length}s")
length = 0.01s

Plot the waveform.

>>> import matplotlib.pyplot as plt
>>> import numpy as np
>>> time = np.linspace(0., length, data.shape[0])
>>> plt.plot(time, data[:, 0], label="Left channel")
>>> plt.plot(time, data[:, 1], label="Right channel")
>>> plt.legend()
>>> plt.xlabel("Time [s]")
>>> plt.ylabel("Amplitude")
>>> plt.show()