1MP4(3) MP4 File Format Library MP4(3)
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6 MP4SetHintTrackRtpPayload - Set the RTP payload parameters of the hint
7 track
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10 #include <mp4.h>
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12 bool MP4SetHintTrackRtpPayload(
13 MP4FileHandle hFile,
14 MP4TrackId hintTrackId,
15 const char* pPayloadName,
16 u_int8_t* pPayloadNumber,
17 u_int16_t maxPayloadSize = 0
18 bool include_rtp_map = true
19 bool include_mpeg4_esid = true
20 )
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23 hFile Specifies the mp4 file to which the operation applies.
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25 hintTrackId
26 Specifies the hint track to which the operation applies.
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28 pPayloadName
29 Specifies the RTP payload name.
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31 pPayloadNumber
32 Specifies a pointer to the RTP payload number.
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34 maxPayloadSize
35 Specifies the maximum RTP payload size in bytes.
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37 include_rtp_map
38 Specifies if the a=rtpmap statement is included.
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40 include_mpeg4_esid
41 Specifies if the a=mpeg4-esid statement is included.
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44 Upon success, true (1). Upon an error, false (0).
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47 MP4SetHintTrackRtpPayload sets the RTP payload parameters for the hint
48 track. The RTP payload is the set of rules by which media samples are
49 packed into RTP packets.
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51 The payload name identifies which RTP payload is being used for the RTP
52 packets created from the hint track. This value is sent to the receiver
53 in the SDP description. For example, MP3 audio sent according to the
54 rules in IETF RFC 2250 uses the name "MPA" for the RTP payload.
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56 The payload number is a shorter form of the payload name. This value is
57 associated with the payload name in the SDP description and then sent
58 in every RTP packet. Payload numbers 1 thru 95 are statically assigned
59 in IETF RFC 1890, numbers 96 thru 127 are dynamically assigned within a
60 session. If the RTP payload in use is one of the statically assigned
61 ones, you should pass this value to the library. If you need a dynamic
62 payload number assigned, pass the define value MP4_SET_DYNAMIC_PAYLOAD
63 for this parameter and the library will choose an valid available num‐
64 ber and return this value.
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66 The maxPayloadSize specifies the maximum number of bytes that should be
67 placed in the RTP payload section of the RTP packets. It is desirable
68 that RTP packets not exceed the maximum transmission unit (MTU) of the
69 IP network they travel over since otherwise the packets must be frag‐
70 mented at the IP level which consumes router resources and can lead to
71 less robust behavior in the face of packet loss.
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73 The default value for maxPayloadSize is 1460, which is the MTU for an
74 Ethernet or similar network minus the standard sizes of the IP, UDP,
75 and RTP headers (1500 - 20 - 8 - 12 = 1460).
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77 If you anticipate streaming over IP networks with smaller MTU sizes, or
78 that extensions to the network headers might be used, a more conserva‐
79 tive value should be chosen. The minimum MTU for an IP network is 576
80 bytes.
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83 MP4(3) MP4GetHintTrackPayload(3)
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87Cisco Systems Inc. Version 0.9 MP4(3)