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afGetFrameSize(3)
=================
NAME
----
afGetFrameSize - calculate the frame size in bytes for an audio track
SYNOPSIS
--------
#include <audiofile.h>
float afGetFrameSize (AFfilehandle file, int track, int expand3to4);
PARAMETERS
----------
'file' is a valid AFfilehandle.
'track' is an integer which refers to a specific audio track in the
file. At present no supported audio file format allows for more than
one audio track within a file, so track should always be
`AF_DEFAULT_TRACK`.
'expand3to4' is a boolean-valued integer indicating whether frame size
calculation will treat 24-bit data as having a size of 3 bytes or 4
bytes.
DESCRIPTION
-----------
`afGetFrameSize` returns the number of bytes in a frame in a given
audio track.
A sample frame consists of one or more samples. For a monaural track,
a sample frame will always contain one sample. For a stereophonic
track, a sample frame will always contain two samples, one for the left
channel and one for the right channel.
A non-zero value of 'expand3to4' should be used when calculating the
frame size for storage in memory (since 24-bit audio data is presented
in memory as a 4-byte sign-extended integer), while a value of zero
should be used for calculating storage on disk where no padding is added.
The parameter 'expand3to4' is ignored unless the specified audio track
contains 24-bit audio data.
AUTHOR
------
Michael Pruett <michael@68k.org>
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