Module audioopy.aio

Class WaveIO

Description

Opening and saving Waveform Audio File Format (WAV) files.

It extends the AudioPCM class to provide functionality for opening and saving audio files in the Waveform Audio File Format (WAV). Waveform Audio File Format is a Microsoft and IBM audio file format standard for storing an audio bitstream on PCs. It is an application of the Resource Interchange File Format (RIFF) bitstream format method for storing data in "chunks".

Example

 >>> # Create an instance and open the WAV file
 >>> wave_io = WaveIO()
 >>> wave_io.open("input.wav")
 >>> # Save the audio content to a new WAV file
 >>> wave_io.save("output.wav")
 >>> # Save a fragment of the audio content to a new WAV file
 >>> frames = wave_io.read_frames(1000)
 >>> wave_io.save_fragment("fragment.wav", frames)

Constructor

Create a WaveIO instance.

View Source

def __init__(self):
    """Create a WaveIO instance."""
    super(WaveIO, self).__init__()

Public functions

open

Get an audio from a Waveform Audio File Format file.

Parameters

filename(str) input file name.

Raises

wave.Error: if the file cannot be opened.

View Source

def open(self, filename: str) -> None:
    """Get an audio from a Waveform Audio File Format file.

        :param filename (str) input file name.
        :raises: wave.Error: if the file cannot be opened.

        """
    self._audio_fp = wave.open(filename, 'r')

save

Write an audio content as a Waveform Audio File Format file.

Parameters

filename(str) output filename.

View Source

def save(self, filename: str) -> None:
    """Write an audio content as a Waveform Audio File Format file.

        :param filename (str) output filename.

        """
    if self._audio_fp is not None:
        self.rewind()
        frames = self._audio_fp.readframes(self._audio_fp.getnframes())
        self.save_fragment(filename, frames)
    elif len(self._channels) == 1:
        channel = self._channels[0]
        f = wave.Wave_write(filename)
        f.setnchannels(1)
        f.setsampwidth(channel.get_sampwidth())
        f.setframerate(channel.get_framerate())
        try:
            f.writeframes(channel.get_frames())
        finally:
            f.close()
    else:
        self.verify_channels()
        sw = self._channels[0].get_sampwidth()
        frames = b''
        for i in range(0, self._channels[0].get_nframes() * sw, sw):
            for j in range(len(self._channels)):
                frames += self._channels[j].get_frames(sw)
        f = wave.Wave_write(filename)
        f.setnchannels(len(self._channels))
        f.setsampwidth(self._channels[0].get_sampwidth())
        f.setframerate(self._channels[0].get_framerate())
        try:
            f.writeframes(frames)
        finally:
            f.close()

save_fragment

Write an audio content as a Waveform Audio File Format file.

Parameters

filename: (str) output filename.
frames: (bytes) the frames to write

View Source

def save_fragment(self, filename: str, frames: bytes) -> None:
    """Write an audio content as a Waveform Audio File Format file.

        :param filename: (str) output filename.
        :param frames: (bytes) the frames to write

        """
    f = wave.Wave_write(filename)
    f.setnchannels(self.get_nchannels())
    f.setsampwidth(self.get_sampwidth())
    f.setframerate(self.get_framerate())
    try:
        f.writeframes(frames)
    finally:
        f.close()