47 lines
1.4 KiB
Plaintext
47 lines
1.4 KiB
Plaintext
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afGetFrameSize(3)
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=================
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NAME
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----
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afGetFrameSize - calculate the frame size in bytes for an audio track
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SYNOPSIS
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--------
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#include <audiofile.h>
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float afGetFrameSize (AFfilehandle file, int track, int expand3to4);
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PARAMETERS
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----------
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'file' is a valid AFfilehandle.
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'track' is an integer which refers to a specific audio track in the
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file. At present no supported audio file format allows for more than
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one audio track within a file, so track should always be
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`AF_DEFAULT_TRACK`.
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'expand3to4' is a boolean-valued integer indicating whether frame size
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calculation will treat 24-bit data as having a size of 3 bytes or 4
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bytes.
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DESCRIPTION
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-----------
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`afGetFrameSize` returns the number of bytes in a frame in a given
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audio track.
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A sample frame consists of one or more samples. For a monaural track,
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a sample frame will always contain one sample. For a stereophonic
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track, a sample frame will always contain two samples, one for the left
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channel and one for the right channel.
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A non-zero value of 'expand3to4' should be used when calculating the
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frame size for storage in memory (since 24-bit audio data is presented
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in memory as a 4-byte sign-extended integer), while a value of zero
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should be used for calculating storage on disk where no padding is added.
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The parameter 'expand3to4' is ignored unless the specified audio track
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contains 24-bit audio data.
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AUTHOR
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------
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Michael Pruett <michael@68k.org>
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