mp4gettrackaudiotype.3

完整的RTP RTSP代码库

.TH "MP4" "3" "Version 0.9" "Cisco Systems Inc." "MP4 File Format Library"
.SH "NAME"
.LP 
\fBMP4GetTrackAudioType\fR \- Get the encoding type of an audio track
.SH "SYNTAX"
.LP 
#include <mp4.h>
.LP 
u_int8_t \fBMP4GetTrackAudioType\fR(
.br 
	MP4FileHandle \fIhFile\fP,
.br 
	MP4TrackId \fItrackId\fP
.br 
)
.SH "ARGUMENTS"
.LP 
.TP 
\fIhFile\fP
Specifies the mp4 file to which the operation applies.
.TP 
\fItrackId\fP
Specifies the track for which the audio type is desired.
.SH "RETURN VALUES"
.LP 
Upon success, the audio type of the track. Upon error, MP4_INVALID_AUDIO_TYPE is returned.
.SH "DESCRIPTION"
.LP 
\fBMP4GetTrackAudioType\fR returns the encoding type of the specified audio track in the mp4 file.
.LP 
Known audio encoding types are:
.LP 
MP4_MPEG1_AUDIO_TYPE	
.br 
	MPEG\-1 Audio Layers I, II, & III
.LP 
MP4_MPEG2_AUDIO_TYPE	
.br 
	MPEG\-2 low bitrate extensions to MPEG\-1 Audio
.br 
	MP4_MP3_AUDIO_TYPE is an alias for this value
.LP 
MP4_MPEG2_AAC_MAIN_AUDIO_TYPE
.br 
	MPEG\-2 AAC Main profile
.LP 
MP4_MPEG2_AAC_LC_AUDIO_TYPE	
.br 
	MPEG\-2 AAC Low Complexity profile
.LP 
MP4_MPEG2_AAC_SSR_AUDIO_TYPE 
.br 
	MPEG\-2 AAC SSR profile
.LP 
MP4_MPEG4_AUDIO_TYPE	
.br 
	MPEG\-4 Audio, includes MPEG\-4 extensions to AAC
.LP 
MP4_PRIVATE_AUDIO_TYPE
.br 
	User private type
.SH "SEE ALSO"
.LP 
MP4(3) MP4AddAudioTrack(3)