afSetVirtualByteOrder, afSetVirtualChannels,
afSetVirtualPCMMapping, afSetVirtualSampleFormat - set the virtual data
format for a track in an audio file
#include <audiofile.h>
int afSetVirtualByteOrder (AFfilehandle file, int track, int byteOrder);
int afSetVirtualChannels (AFfilehandle file, int track, int channels);
int afSetVirtualSampleFormat (AFfilehandle file, int track,
int sampleFormat, int sampleWidth);
int afSetVirtualPCMMapping (AFfilehandle file, int track,
double slope, double intercept, double minclip, double maxclip);
• file is an AFfilehandle which refers to
an open audio file and is usually created by afOpenFile.
• track is an integer which identifies a
particular track in an open audio file. The only valid track is
AF_DEFAULT_TRACK for all currently supported file formats.
• sampleFormat is an integer which denotes
a virtual sample format. Valid values are AF_SAMPFMT_TWOSCOMP,
AF_SAMPFMT_UNSIGNED, AF_SAMPFMT_FLOAT, and AF_SAMPFMT_DOUBLE.
• sampleWidth is a positive integer which
specifies the number of bits in a sample.
• channels is a positive integer which
specifies the number of interleaved audio channels in the given audio
track.
• byteOrder is an integer which specifies
the virtual byte order of samples in the given audio track. byteOrder
can be either AF_BYTEORDER_BIGENDIAN or AF_BYTEORDER_LITTLEENDIAN.
• slope and intercept are
double-precision floating point values which indicate the audio data sample
slope and zero-crossing value, respectively, for the given sample
format.
• minclip and maxclip are
double-precision floating point values which indicates the minimum or maximum
sample values to be returned. Any values less than minclip will be set
to minclip, and any values greater than maxclip will be set to
maxclip.
These functions return 0 for success and -1 for failure.
Michael Pruett <michael@68k.org>