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// VP9 Video RTP Sources
19// Implementation
20
21#include "VP9VideoRTPSource.hh"
22
23VP9VideoRTPSource*
24VP9VideoRTPSource::createNew(UsageEnvironment& env, Groupsock* RTPgs,
25 unsigned char rtpPayloadFormat,
26 unsigned rtpTimestampFrequency) {
27 return new VP9VideoRTPSource(env, RTPgs, rtpPayloadFormat,
28 rtpTimestampFrequency);
29}
30
31VP9VideoRTPSource
32::VP9VideoRTPSource(UsageEnvironment& env, Groupsock* RTPgs,
33 unsigned char rtpPayloadFormat,
34 unsigned rtpTimestampFrequency)
35 : MultiFramedRTPSource(env, RTPgs, rtpPayloadFormat, rtpTimestampFrequency) {
36}
37
38VP9VideoRTPSource::~VP9VideoRTPSource() {
39}
40
41#define incrHeader do { ++resultSpecialHeaderSize; ++headerStart; if (--packetSize == 0) return False; } while (0)
42
43Boolean VP9VideoRTPSource
44::processSpecialHeader(BufferedPacket* packet,
45 unsigned& resultSpecialHeaderSize) {
46 unsigned char* headerStart = packet->data();
47 unsigned packetSize = packet->dataSize();
48
49 // Figure out the size of the special header.
50 if (packetSize == 0) return False; // error
51 resultSpecialHeaderSize = 1; // unless we learn otherwise
52
53 u_int8_t const byte1 = *headerStart;
54 Boolean const I = (byte1&0x80) != 0;
55 Boolean const L = (byte1&0x40) != 0;
56 Boolean const F = (byte1&0x20) != 0;
57 Boolean const B = (byte1&0x10) != 0;
58 Boolean const E = (byte1&0x08) != 0;
59 Boolean const V = (byte1&0x04) != 0;
60 Boolean const U = (byte1&0x02) != 0;
61
62 fCurrentPacketBeginsFrame = B;
63 fCurrentPacketCompletesFrame = E;
64 // use this instead of the RTP header's 'M' bit (which might not be accurate)
65
66 if (I) { // PictureID present
67 incrHeader;
68 Boolean const M = ((*headerStart)&0x80) != 0;
69 if (M) incrHeader;
70 }
71
72 if (L) { // Layer indices present
73 incrHeader;
74 if (F) { // Reference indices present
75 incrHeader;
76 unsigned R = (*headerStart)&0x03;
77 while (R-- > 0) {
78 incrHeader;
79 Boolean const X = ((*headerStart)&0x10) != 0;
80 if (X) incrHeader;
81 }
82 }
83 }
84
85 if (V) { // Scalability Structure (SS) present
86 incrHeader;
87 unsigned patternLength = *headerStart;
88 while (patternLength-- > 0) {
89 incrHeader;
90 unsigned R = (*headerStart)&0x03;
91 while (R-- > 0) {
92 incrHeader;
93 Boolean const X = ((*headerStart)&0x10) != 0;
94 if (X) incrHeader;
95 }
96 }
97 }
98
99 if (U) { // Scalability Structure Update (SU) present
100 return False; // This structure isn't yet defined in the VP9 payload format I-D
101 }
102
103 return True;
104}
105
106char const* VP9VideoRTPSource::MIMEtype() const {
107 return "video/VP9";
108}
109