AFGETFRAMECOUNT(3) 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
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>
Audio File Library 0.3.6 03/06/2013 AFGETFRAMECOUNT(3)