'\" t .\" Title: afGetFrameSize .\" Author: [see the "AUTHOR" section] .\" Generator: DocBook XSL Stylesheets v1.76.1 .\" Date: 03/06/2013 .\" Manual: \ \& .\" Source: Audio File Library 0.3.6 .\" Language: English .\" .TH "AFGETFRAMESIZE" "3" "03/06/2013" "Audio File Library 0\&.3\&.6" "\ \&" .\" ----------------------------------------------------------------- .\" * Define some portability stuff .\" ----------------------------------------------------------------- .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .\" http://bugs.debian.org/507673 .\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" ----------------------------------------------------------------- .\" * set default formatting .\" ----------------------------------------------------------------- .\" disable hyphenation .nh .\" disable justification (adjust text to left margin only) .ad l .\" ----------------------------------------------------------------- .\" * MAIN CONTENT STARTS HERE * .\" ----------------------------------------------------------------- .SH "NAME" afGetFrameSize \- calculate the frame size in bytes for an audio track .SH "SYNOPSIS" .sp .nf #include .fi .sp .nf float afGetFrameSize (AFfilehandle file, int track, int expand3to4); .fi .SH "PARAMETERS" .sp \fIfile\fR is a valid AFfilehandle\&. .sp \fItrack\fR is an integer which refers to a specific audio track in the file\&. At present no supported audio file format allows for more than one audio track within a file, so track should always be AF_DEFAULT_TRACK\&. .sp \fIexpand3to4\fR is a boolean\-valued integer indicating whether frame size calculation will treat 24\-bit data as having a size of 3 bytes or 4 bytes\&. .SH "DESCRIPTION" .sp afGetFrameSize returns the number of bytes in a frame in a given audio track\&. .sp A sample frame consists of one or more samples\&. For a monaural track, a sample frame will always contain one sample\&. For a stereophonic track, a sample frame will always contain two samples, one for the left channel and one for the right channel\&. .sp A non\-zero value of \fIexpand3to4\fR should be used when calculating the frame size for storage in memory (since 24\-bit audio data is presented in memory as a 4\-byte sign\-extended integer), while a value of zero should be used for calculating storage on disk where no padding is added\&. The parameter \fIexpand3to4\fR is ignored unless the specified audio track contains 24\-bit audio data\&. .SH "AUTHOR" .sp Michael Pruett