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afGetFrameCount(3)
==================
NAME
----
afGetFrameCount, afGetTrackBytes, afGetDataOffset - get the total sample
frame count, length of audio track in bytes, offset of the audio track for a
track in an audio file
SYNOPSIS
--------
#include <audiofile.h>
AFframecount afGetFrameCount (AFfilehandle file, int track);
AFfileoffset afGetTrackBytes (AFfilehandle file, int track);
AFfileoffset afGetDataOffset (AFfilehandle file, int track);
PARAMETERS
----------
'file' is an audio file handle created by a previous call to
linkaf:afOpenFile[3].
'track' is an integer which specifies an audio track within 'file'.
All supported file formats contain exactly one audio track per file,
so the constant `AF_DEFAULT_TRACK` should always be used.
DESCRIPTION
-----------
`afGetFrameCount` returns the total number of sample frames contained
within the specified track of the specified file.
Each sample frame of audio consists of a fixed number of samples
(equal to the number of audio channels in the track. For monaural data,
a sample frame consists of one audio sample. For stereophonic data,
a sample frame consists of a stereo pair.
`afGetTrackBytes` returns the total number of bytes of raw audio data
(i.e., prior to decompression or conversion) in the track.
`afGetDataOffset` returns the offset in bytes of the start of the audio
data contained within the specified track of the specified file.
RETURN VALUE
------------
`afGetFrameCount` returns the total number of sample frames in 'track'.
`afGetTrackBytes` returns the total number of bytes of audio data
in 'track'.
`afGetDataOffset` returns the offset in bytes to the beginning of the
audio data in 'track'.
Each of these routines returns -1 in case of error.
AUTHOR
------
Michael Pruett <michael@68k.org>
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