mp4convertfromtrackduration.3

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.TH "MP4" "3" "Version 0.9" "Cisco Systems Inc." "MP4 File Format Library"
.SH "NAME"
.LP 
\fBMP4ConvertFromTrackDuration\fR \- Convert a duration from the track time scale to a specified time scale.
.SH "SYNTAX"
.LP 
#include <mp4.h>
.LP 
u_int64_t \fBMP4ConvertFromTrackDuration\fR(
.br 
	MP4FileHandle \fIhFile\fP,
.br 
	MP4TrackId \fItrackId\fP,
.br 
	MP4Duration \fIduration\fP,
.br 
	u_int32_t \fInewTimeScale\fP
.br 
)
.SH "ARGUMENTS"
.LP 
.TP 
\fIhFile\fP
Specifies the mp4 file to which the operation applies.
.TP 
\fItrackId\fP
Specifies the track from which the duration originates.
.TP 
\fIduration\fP
Specifies the duration that is to be converted.
.TP 
\fInewTimeScale\fP
Specifies the new time scale in ticks per second to which the duration should be converted.
.SH "RETURN VALUES"
.LP 
Upon success, the duration in the new time scale units. Upon error, 0.
.SH "DESCRIPTION"
.LP 
\fBMP4ConvertFromTrackDuration\fR converts a duration such as a sample duration from the track time scale to another specified time scale. This can be used by a player application to map all track samples to a common time scale.

.SH "SEE ALSO"
.LP 
MP4(3) MP4GetSampleDuration(3) MP4ConvertToTrackDuration(3)