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NAME
Snack_GetSampleRate, Snack_SetSampleRate, Snack_GetSampleEncoding, Snack_SetSampleEncoding,
Snack_GetNumChannels, Snack_SetNumChannels, Snack_GetBytesPerSample, Snack_SetBytesPerSample,
Snack_GetSoundFilename, Snack_SetHeaderSize - macros to set/get properties
of Snack sound objects
SYNOPSIS
#include <snack.h>
Snack_GetSampleRate(sound)
Snack_SetSampleRate(sound, frequency)
Snack_GetSampleEncoding(sound)
Snack_SetSampleEncoding(sound, format)
Snack_GetNumChannels(sound)
Snack_SetNumChannels(sound, numChannels)
Snack_GetBytesPerSample(sound)
Snack_SetBytesPerSample(sound, size)
Snack_SetHeaderSize(sound, size)
Snack_GetSoundFilename(sound)
ARGUMENTS
Sound *sound (in)
A pointer to a sound object to query or modify
int frequency (in)
A positive integer specifying the sample rate of
the sound.
int format (in)
An integer used to specify sample encoding format.
Use one of these definitions LIN16, MULAW, ALAW, LIN8OFFSET, LIN8, LIN24,
LIN32, SNACK_FLOAT, or SNACK_DOUBLE
int numChannels (in)
A positive integer specifying the number of separate
channels of a sound
int size (in)
A size specification measured in bytes
DESCRIPTION
The following functions are implemented as macros. Snack_GetLength
returns the length of a sound in number of frames, for mono sounds this
is equal to the number of samples. Snack_SetLength is used to specify
the length of the sound. No storage is allocated/freed as a result of this,
the function Snack_ResizeSoundStorage must be used to the perform
actual storage management. Snack_GetFrequency and Snack_SetFrequency
control the sampling frequency of a Snack sound object. Most audio devices
only allow certain specific values for playback and recording. Common values
are 8000, 11025, 16000, 22050, 32000, 44100, and 48000. Snack_GetNumChannels
and Snack_SetNumChannels handle the number of channels of the sound,
either a positive integer or MONO/STEREO/QUAD. Snack_GetSampleFormat
and
Snack_SetSampleFormat
control the sample encoding format. Use the constants LIN16, MULAW, ALAW,
LIN8OFFSET, LIN8, LIN24, LIN32, SNACK_FLOAT, or SNACK_DOUBLE. Snack_GetBytesPerSample
and Snack_SetBytesPerSample should be used in conjunction with the
previous pair. For LIN16 the number of bytes per sample is 2. No checks
are performed for any arguments to these functions. Snack_GetSoundFilename
is used to retrieve a pointer to the filename string which is or last was
associated with the sound object.
Snack_SetHeaderSize is used, in
code that defines new sound file formats, to specify how large (in bytes)
the header of the sound file is.
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