afGetAESChannelData(3dm)afGetAESChannelData(3dm)NAME
afGetAESChannelData, afSetAESChannelData - get/set AES channel status
information in an AFfilehandle structure for an audio track
SYNOPSIS
#include <dmedia/audiofile.h>
int afGetAESChannelData(AFfilehandle file, int track,
unsigned char buf[24])
void afSetAESChannelData(AFfilehandle file, int track,
unsigned char buf[24])
PARAMETER
file expects an AFfilehandle structure, previously created by a call
to afOpenFile(3dm).
track expects an integer which identifies the audio track in the file.
Since all currently supported file formats allow at most one
audio track per file, the constant value AF_DEFAULT_TRACK should
always be used for this argument for now.
buf is a data buffer used to pass the 24 bytes of AES channel status
data to afSetAESChannelData(), or to obtain the 24 bytes of AES
channel status data from afGetAESChannelData().
RETURN VALUEafGetAESChannelData() returns 0 if there is no AES channel status
information associated with the given track, 1 if there is AES data, and
-1 in the event of an error.
DESCRIPTIONafSetAESChannelData() writes the specified AES channel status data bytes
into the appropriate header location of file. If no header space has
been reserved in the header by afInitAESChannelData(3dm), the routine
will ignore the data and return.
afGetAESChannelData() copies the channel status data for track into buf.
If no AES channel status data is found, it returns 0.
CAVEATS
These functions will always manipulate data that is to be interpreted as
AES channel status data, but there is never any guarantee that such data
will be present in a given input file or not, or will be allowed in a
given output file or not (unless the file format of the file being read
or written requires that AES data is always present). Even in the
formats AIFF and AIFF-C, the presence of AES channel status data is
optional.
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afGetAESChannelData(3dm)afGetAESChannelData(3dm)SEE ALSOafOpenFile(3dm), afReadFrames(3dm), afInitChannels(3dm), aifc(4)
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