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// RTP sink for MPEG-4 Elementary Stream video (RFC 3016)
19// Implementation
20
21#include "MPEG4ESVideoRTPSink.hh"
22#include "MPEG4VideoStreamFramer.hh"
23#include "MPEG4LATMAudioRTPSource.hh" // for "parseGeneralConfigStr()"
24
25MPEG4ESVideoRTPSink
26::MPEG4ESVideoRTPSink(UsageEnvironment& env, Groupsock* RTPgs, unsigned char rtpPayloadFormat, u_int32_t rtpTimestampFrequency,
27 u_int8_t profileAndLevelIndication, char const* configStr)
28 : VideoRTPSink(env, RTPgs, rtpPayloadFormat, rtpTimestampFrequency, "MP4V-ES"),
29 fVOPIsPresent(False), fProfileAndLevelIndication(profileAndLevelIndication), fFmtpSDPLine(NULL) {
30 fConfigBytes = parseGeneralConfigStr(configStr, fNumConfigBytes);
31}
32
33MPEG4ESVideoRTPSink::~MPEG4ESVideoRTPSink() {
34 delete[] fFmtpSDPLine;
35 delete[] fConfigBytes;
36}
37
38MPEG4ESVideoRTPSink*
39MPEG4ESVideoRTPSink::createNew(UsageEnvironment& env,
40 Groupsock* RTPgs, unsigned char rtpPayloadFormat,
41 u_int32_t rtpTimestampFrequency) {
42 return new MPEG4ESVideoRTPSink(env, RTPgs, rtpPayloadFormat, rtpTimestampFrequency);
43}
44
45MPEG4ESVideoRTPSink*
46MPEG4ESVideoRTPSink::createNew(UsageEnvironment& env,
47 Groupsock* RTPgs, unsigned char rtpPayloadFormat, u_int32_t rtpTimestampFrequency,
48 u_int8_t profileAndLevelIndication, char const* configStr) {
49 return new MPEG4ESVideoRTPSink(env, RTPgs, rtpPayloadFormat, rtpTimestampFrequency, profileAndLevelIndication, configStr);
50}
51
52Boolean MPEG4ESVideoRTPSink::sourceIsCompatibleWithUs(MediaSource& source) {
53 // Our source must be an appropriate framer:
54 return source.isMPEG4VideoStreamFramer();
55}
56
57#define VOP_START_CODE 0x000001B6
58
59void MPEG4ESVideoRTPSink
60::doSpecialFrameHandling(unsigned fragmentationOffset,
61 unsigned char* frameStart,
62 unsigned numBytesInFrame,
63 struct timeval framePresentationTime,
64 unsigned numRemainingBytes) {
65 if (fragmentationOffset == 0) {
66 // Begin by inspecting the 4-byte code at the start of the frame:
67 if (numBytesInFrame < 4) return; // shouldn't happen
68 u_int32_t startCode
69 = (frameStart[0]<<24) | (frameStart[1]<<16) | (frameStart[2]<<8) | frameStart[3];
70
71 fVOPIsPresent = startCode == VOP_START_CODE;
72 }
73
74 // Set the RTP 'M' (marker) bit iff this frame ends a VOP
75 // (and there are no fragments remaining).
76 // This relies on the source being a "MPEG4VideoStreamFramer".
77 MPEG4VideoStreamFramer* framerSource = (MPEG4VideoStreamFramer*)fSource;
78 if (framerSource != NULL && framerSource->pictureEndMarker()
79 && numRemainingBytes == 0) {
80 setMarkerBit();
81 framerSource->pictureEndMarker() = False;
82 }
83
84 // Also set the RTP timestamp. (We do this for each frame
85 // in the packet, to ensure that the timestamp of the VOP (if present)
86 // gets used.)
87 setTimestamp(framePresentationTime);
88}
89
90Boolean MPEG4ESVideoRTPSink::allowFragmentationAfterStart() const {
91 return True;
92}
93
94Boolean MPEG4ESVideoRTPSink
95::frameCanAppearAfterPacketStart(unsigned char const* /*frameStart*/,
96 unsigned /*numBytesInFrame*/) const {
97 // Once we've packed a VOP into the packet, then no other
98 // frame can be packed into it:
99 return !fVOPIsPresent;
100}
101
102char const* MPEG4ESVideoRTPSink::auxSDPLine() {
103 // Generate a new "a=fmtp:" line each time, using our own 'configuration' information (if we have it),
104 // otherwise parameters from our framer source (in case they've changed since the last time that
105 // we were called):
106 unsigned configLength = fNumConfigBytes;
107 unsigned char* config = fConfigBytes;
108 if (fProfileAndLevelIndication == 0 || config == NULL) {
109 // We need to get this information from our framer source:
110 MPEG4VideoStreamFramer* framerSource = (MPEG4VideoStreamFramer*)fSource;
111 if (framerSource == NULL) return NULL; // we don't yet have a source
112
113 fProfileAndLevelIndication = framerSource->profile_and_level_indication();
114 if (fProfileAndLevelIndication == 0) return NULL; // our source isn't ready
115
116 config = framerSource->getConfigBytes(configLength);
117 if (config == NULL) return NULL; // our source isn't ready
118 }
119
120 char const* fmtpFmt =
121 "a=fmtp:%d "
122 "profile-level-id=%d;"
123 "config=";
124 unsigned fmtpFmtSize = strlen(fmtpFmt)
125 + 3 /* max char len */
126 + 3 /* max char len */
127 + 2*configLength /* 2*, because each byte prints as 2 chars */
128 + 2 /* trailing \r\n */;
129 char* fmtp = new char[fmtpFmtSize];
130 sprintf(fmtp, fmtpFmt, rtpPayloadType(), fProfileAndLevelIndication);
131 char* endPtr = &fmtp[strlen(fmtp)];
132 for (unsigned i = 0; i < configLength; ++i) {
133 sprintf(endPtr, "%02X", config[i]);
134 endPtr += 2;
135 }
136 sprintf(endPtr, "\r\n");
137
138 delete[] fFmtpSDPLine;
139 fFmtpSDPLine = strDup(fmtp);
140 delete[] fmtp;
141 return fFmtpSDPLine;
142}
143