aifc.open
?This module makes it possible to read and write AIFF and AIFF-C files. AIFF stands for Audio Interchange File Format, which is a file format for storing digital audio samples. AIFF-C is a newer version of the format that allows audio data to be compressed.
There are various parameters in audio files that describe the audio data. The number of times per second that sound is sampled is known as the frame rate or sampling rate. If the audio is mono, stereo, or quadro, the number of channels reflects that. Each channel has one sample in each frame.
Each sample’s size in bytes is known as the sample size. A frame is made up of nchannels * sample size bytes, while a second is made up of nchannels * sample size bytes.
CD grade audio, for example, has a sample size of two bytes (16 bits), two channels (stereo), and a frame rate of 44,100 frames per second. A second’s worth of data takes up 2244100 bytes, giving a frame size of 4 bytes (2*2). (176,400 bytes).
The following function is defined by module aifc:
import aifc
obj = aifc.open('sound.aiff','r')
aifc.open()
: This function opens an AIFF or AIFF-C file and returns an instance of an object for reading or writing audio data. If the file must be opened for reading, it must be ‘r’ or ‘rb’. When the file must be opened for writing, it should be ‘w’ or ‘wb.’In write mode, the object uses the following functions:
aiff()
: An AIFF file is created as a result of this.
aifc()
: An AIFF-C file is created as a result of this.
aifc.setnchannels()
: The number of channels in the audio file is specified.
aifc.setsampwidth()
: Defines the size of audio samples in bytes.
aifc.setframerate()
: The sampling frequency in frames per second is specified.
aifc.setnframes()
: This specifies the number of frames to be written to the audio file.
aifc.setcomptype()
: This determines the compression method. Compression of an AIFF file is not possible. b’NONE’, b’ULAW’, b’ALAW’, and b’G722’ compression types are supported.
aifc.setparams()
: This function sets all of the above parameters at the same time.
aifc.writeframes()
: This causes data to be written to the output file.
When a file is opened for reading, open()
returns an object with the following methods:
aifc.getnchannels()
:
This represents the number of audio channels.print( "Number of channels",obj.getnchannels())
aifc.getsampwidth()
:
Return the size of individual samples in bytes.print ( "Sample width",obj.getsampwidth())
aifc.getnframes()
:
The number of audio frames in the file is returned.print ("Number of frames",obj.getnframes())
aifc.getcomptype()
:
Return a bytes array of length 4 describing the audio file’s compression type. The returned value for AIFF files is b’NONE’.
aifc.getcompname()
:
Return a bytes array that can be converted to a human-readable description of the audio file’s compression type.