mp4convertfromtracktimestamp.3

网络MPEG4IP流媒体开发源代码

.TH "MP4" "3" "Version 0.9" "Cisco Systems Inc." "MP4 File Format Library"
.SH "NAME"
.LP 
\fBMP4ConvertFromTrackTimestamp\fR \- Convert a timestamp from the track time scale to a specified time scale.
.SH "SYNTAX"
.LP 
#include <mp4.h>
.LP 
u_int64_t \fBMP4ConvertFromTrackTimestamp\fR(
.br 
	MP4FileHandle \fIhFile\fP,
.br 
	MP4TrackId \fItrackId\fP,
.br 
	MP4Timestamp \fItimestamp\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 timestamp originates.
.TP 
\fItimestamp\fP
Specifies the timestamp that is to be converted.
.TP 
\fInewTimeScale\fP
Specifies the new time scale in ticks per second to which the timestamp should be converted.
.SH "RETURN VALUES"
.LP 
Upon success, the timestamp in the new time scale units. Upon error, 0xFFFFFFFFFFFFFFFF.
.SH "DESCRIPTION"
.LP 
\fBMP4ConvertFromTrackTimestamp\fR converts a timestamp such as a sample start time 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) MP4ConvertToTrackTimestamp(3)