'\" t
.\"     Title: afSetVirtualSampleFormat
.\"    Author: [see the "AUTHOR" section]
.\" Generator: DocBook XSL Stylesheets v1.76.1 <http://docbook.sf.net/>
.\"      Date: 03/06/2013
.\"    Manual: \ \&
.\"    Source: Audio File Library 0.3.6
.\"  Language: English
.\"
.TH "AFSETVIRTUALSAMPLEFO" "3" "03/06/2013" "Audio File Library 0\&.3\&.6" "\ \&"
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.SH "NAME"
afSetVirtualByteOrder, afSetVirtualChannels, afSetVirtualPCMMapping, afSetVirtualSampleFormat \- set the virtual data format for a track in an audio file
.SH "SYNOPSIS"
.sp
.nf
#include <audiofile\&.h>
.fi
.sp
.nf
int afSetVirtualByteOrder (AFfilehandle file, int track, int byteOrder);
.fi
.sp
.nf
int afSetVirtualChannels (AFfilehandle file, int track, int channels);
.fi
.sp
.nf
int afSetVirtualSampleFormat (AFfilehandle file, int track,
    int sampleFormat, int sampleWidth);
.fi
.sp
.nf
int afSetVirtualPCMMapping (AFfilehandle file, int track,
    double slope, double intercept, double minclip, double maxclip);
.fi
.SH "PARAMETERS"
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}

\fIfile\fR
is an AFfilehandle which refers to an open audio file and is usually created by afOpenFile\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}

\fItrack\fR
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\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}

\fIsampleFormat\fR
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\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}

\fIsampleWidth\fR
is a positive integer which specifies the number of bits in a sample\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}

\fIchannels\fR
is a positive integer which specifies the number of interleaved audio channels in the given audio track\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}

\fIbyteOrder\fR
is an integer which specifies the virtual byte order of samples in the given audio track\&.
\fIbyteOrder\fR
can be either
AF_BYTEORDER_BIGENDIAN
or
AF_BYTEORDER_LITTLEENDIAN\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}

\fIslope\fR
and
\fIintercept\fR
are double\-precision floating point values which indicate the audio data sample slope and zero\-crossing value, respectively, for the given sample format\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}

\fIminclip\fR
and
\fImaxclip\fR
are double\-precision floating point values which indicates the minimum or maximum sample values to be returned\&. Any values less than
\fIminclip\fR
will be set to
\fIminclip\fR, and any values greater than
\fImaxclip\fR
will be set to
\fImaxclip\fR\&.
.RE
.SH "RETURN VALUE"
.sp
These functions return 0 for success and \-1 for failure\&.
.SH "AUTHOR"
.sp
Michael Pruett <michael@68k\&.org>