1MP4(3) MP4 File Format Library MP4(3)
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6 MP4FindTrackId - Find a track id
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9 #include <mp4.h>
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11 MP4TrackId MP4FindTrackId(
12 MP4FileHandle hFile,
13 u_int16_t index,
14 const char* type = NULL,
15 u_int8_t subType = 0
16 )
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19 hFile Specifies the mp4 file to which the operation applies.
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21 index Specifies which track is desired from matching tracks.
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23 type Specifies the type of track to be matched. A NULL value implies
24 any type of track. See MP4GetTrackType() for predefined values.
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26 subType
27 Specifies the subtype of the track to be matched. Subtypes are
28 only defined for audio and video tracks, see MP4GetAudioTrackā
29 Type() and MP4GetVideoTrackType() for predefined values. A zero
30 value implies any subtype.
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33 Upon success, the track id of the specified track. Upon an error,
34 MP4_INVALID_TRACK_ID.
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38 MP4FindTrackId gets the track id associated with the index'th track of
39 the specified track type. For example, to get the track id of the first
40 video track:
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42 MP4FindTrackId(hFile, 0, MP4_VIDEO_TRACK_TYPE);
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44 For audio and video tracks, a subtype can be specified to find a track
45 of a particular encoding. For example, to get the track id of the first
46 audio track encoded with MPEG-1 audio:
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48 MP4FindTrackId(hFile, 0, MP4_AUDIO_TRACK_TYPE,
49 MP4_MPEG1_AUDIO_TYPE);
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51 Caveat: The track id's do not imply anything about the ordering of the
52 track information within the mp4 file.
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55 MP4(3) MP4FindTrackIndex(3)
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59Cisco Systems Inc. Version 0.9 MP4(3)