1/**********
2This library is free software; you can redistribute it and/or modify it under
3the terms of the GNU Lesser General Public License as published by the
4Free Software Foundation; either version 3 of the License, or (at your
5option) any later version. (See <http://www.gnu.org/copyleft/lesser.html>.)
6
7This library is distributed in the hope that it will be useful, but WITHOUT
8ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
9FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for
10more details.
11
12You should have received a copy of the GNU Lesser General Public License
13along with this library; if not, write to the Free Software Foundation, Inc.,
1451 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
15**********/
16// "liveMedia"
17// Copyright (c) 1996-2020 Live Networks, Inc. All rights reserved.
18// MPEG4-GENERIC ("audio", "video", or "application") RTP stream sinks
19// Implementation
20
21#include "MPEG4GenericRTPSink.hh"
22#include "Locale.hh"
23#include <ctype.h> // needed on some systems to define "tolower()"
24
25MPEG4GenericRTPSink
26::MPEG4GenericRTPSink(UsageEnvironment& env, Groupsock* RTPgs,
27 u_int8_t rtpPayloadFormat,
28 u_int32_t rtpTimestampFrequency,
29 char const* sdpMediaTypeString,
30 char const* mpeg4Mode, char const* configString,
31 unsigned numChannels)
32 : MultiFramedRTPSink(env, RTPgs, rtpPayloadFormat,
33 rtpTimestampFrequency, "MPEG4-GENERIC", numChannels),
34 fSDPMediaTypeString(strDup(sdpMediaTypeString)),
35 fMPEG4Mode(strDup(mpeg4Mode)), fConfigString(strDup(configString)) {
36 // Check whether "mpeg4Mode" is one that we handle:
37 if (mpeg4Mode == NULL) {
38 env << "MPEG4GenericRTPSink error: NULL \"mpeg4Mode\" parameter\n";
39 } else {
40 // To ease comparison, convert "mpeg4Mode" to lower case:
41 size_t const len = strlen(mpeg4Mode) + 1;
42 char* m = new char[len];
43
44 Locale l("POSIX");
45 for (size_t i = 0; i < len; ++i) m[i] = tolower(mpeg4Mode[i]);
46
47 if (strcmp(m, "aac-hbr") != 0) {
48 env << "MPEG4GenericRTPSink error: Unknown \"mpeg4Mode\" parameter: \"" << mpeg4Mode << "\"\n";
49 }
50 delete[] m;
51 }
52
53 // Set up the "a=fmtp:" SDP line for this stream:
54 char const* fmtpFmt =
55 "a=fmtp:%d "
56 "streamtype=%d;profile-level-id=1;"
57 "mode=%s;sizelength=13;indexlength=3;indexdeltalength=3;"
58 "config=%s\r\n";
59 unsigned fmtpFmtSize = strlen(fmtpFmt)
60 + 3 /* max char len */
61 + 3 /* max char len */
62 + strlen(fMPEG4Mode)
63 + strlen(fConfigString);
64 char* fmtp = new char[fmtpFmtSize];
65 sprintf(fmtp, fmtpFmt,
66 rtpPayloadType(),
67 strcmp(fSDPMediaTypeString, "video") == 0 ? 4 : 5,
68 fMPEG4Mode,
69 fConfigString);
70 fFmtpSDPLine = strDup(fmtp);
71 delete[] fmtp;
72}
73
74MPEG4GenericRTPSink::~MPEG4GenericRTPSink() {
75 delete[] fFmtpSDPLine;
76 delete[] (char*)fConfigString;
77 delete[] (char*)fMPEG4Mode;
78 delete[] (char*)fSDPMediaTypeString;
79}
80
81MPEG4GenericRTPSink*
82MPEG4GenericRTPSink::createNew(UsageEnvironment& env, Groupsock* RTPgs,
83 u_int8_t rtpPayloadFormat,
84 u_int32_t rtpTimestampFrequency,
85 char const* sdpMediaTypeString,
86 char const* mpeg4Mode,
87 char const* configString, unsigned numChannels) {
88 return new MPEG4GenericRTPSink(env, RTPgs, rtpPayloadFormat,
89 rtpTimestampFrequency,
90 sdpMediaTypeString, mpeg4Mode,
91 configString, numChannels);
92}
93
94Boolean MPEG4GenericRTPSink
95::frameCanAppearAfterPacketStart(unsigned char const* /*frameStart*/,
96 unsigned /*numBytesInFrame*/) const {
97 // (For now) allow at most 1 frame in a single packet:
98 return False;
99}
100
101void MPEG4GenericRTPSink
102::doSpecialFrameHandling(unsigned fragmentationOffset,
103 unsigned char* frameStart,
104 unsigned numBytesInFrame,
105 struct timeval framePresentationTime,
106 unsigned numRemainingBytes) {
107 // Set the "AU Header Section". This is 4 bytes: 2 bytes for the
108 // initial "AU-headers-length" field, and 2 bytes for the first
109 // (and only) "AU Header":
110 unsigned fullFrameSize
111 = fragmentationOffset + numBytesInFrame + numRemainingBytes;
112 unsigned char headers[4];
113 headers[0] = 0; headers[1] = 16 /* bits */; // AU-headers-length
114 headers[2] = fullFrameSize >> 5; headers[3] = (fullFrameSize&0x1F)<<3;
115
116 setSpecialHeaderBytes(headers, sizeof headers);
117
118 if (numRemainingBytes == 0) {
119 // This packet contains the last (or only) fragment of the frame.
120 // Set the RTP 'M' ('marker') bit:
121 setMarkerBit();
122 }
123
124 // Important: Also call our base class's doSpecialFrameHandling(),
125 // to set the packet's timestamp:
126 MultiFramedRTPSink::doSpecialFrameHandling(fragmentationOffset,
127 frameStart, numBytesInFrame,
128 framePresentationTime,
129 numRemainingBytes);
130}
131
132unsigned MPEG4GenericRTPSink::specialHeaderSize() const {
133 return 2 + 2;
134}
135
136char const* MPEG4GenericRTPSink::sdpMediaType() const {
137 return fSDPMediaTypeString;
138}
139
140char const* MPEG4GenericRTPSink::auxSDPLine() {
141 return fFmtpSDPLine;
142}
143