afSetLoopStartFrame(3dm)			      afSetLoopStartFrame(3dm)

NAME    [Toc]    [Back]

     afSetLoopStartFrame, afSetLoopEndFrame, afSetLoopCount - set the
     start/end frame and loop count from an AFfilehandle structure for a
     specified loop.

SYNOPSIS    [Toc]    [Back]

     #include <dmedia/audiofile.h>

     int afSetLoopStartFrame(AFfilehandle file,	int instid,
				  int loopid, AFframecount startframe)

     int afSetLoopEndFrame(AFfilehandle	file, int instid,
				  int loopid, AFframecount endframe)

     int afSetLoopCount(AFfilehandle file, int instid,
				  int loopid, int count)

PARAMETER    [Toc]    [Back]

     file     is an AFfilehandle structure, previously created by a call to
	      afOpenFile(3dm).

     instid   is a positive integer value which	identifies an instrument
	      configuration in file.  instid should be an element from an
	      array of IDs created via a call to afInitInstIDs(3dm).

     loopid   is a positive integer value which	identifies a loop structure in
	      an instrument parameter chunk.  You create loopid's by calling
	      afInitLoopIDs(3dm).

RETURN VALUE    [Toc]    [Back]

     All of these routines return 0 on success or -1 if	there is an error.

DESCRIPTION    [Toc]    [Back]

     Each takes	a loopid argument which	provides a handle to a set of loop
     parameters.

     You can create a list of loop ID's	for an audio track by calling
     afInitLoopIDs(3dm).  Logically, an	audio file contains chunks of
     instrument	parameters (specified by instid	handles), and each chunk of
     instrument	parameters may contain several loops.

     AIFF(4) (and AIFF-C) files	contain	at most	one instrument configuration,
     but other file formats may	contain	multiple configurations.  afQuery(3dm)
     should be used to determine in advance whether a particular format
     supports multiple inst chunks.

     These routines allow you to set information about loops in	an audio file
     without the added overhead	of using associated markers (see
     afSetLoopStart(3dm)).  This is necessary because several file formats now
     supported by the Audio File Library contain loop information (i.e., start
     and end points) which is completely independent of	marker information.
     In	other words, the markers (if any) stored in the	file header may	and



									Page 1






afSetLoopStartFrame(3dm)			      afSetLoopStartFrame(3dm)



     usually will refer	to locations in	the file other than the	loop start and
     end points.

SEE ALSO    [Toc]    [Back]

     afOpenFile(3dm), afInitInstIDs(3dm), afSetInstParamLong(3dm),
     afInitLoopIDs(3dm), afSetLoopStart(3dm), aiff(4), avr(4), wave(4),	sd2(4)


									PPPPaaaaggggeeee 2222