| /********** |
| This library is free software; you can redistribute it and/or modify it under |
| the terms of the GNU Lesser General Public License as published by the |
| Free Software Foundation; either version 3 of the License, or (at your |
| option) any later version. (See <http://www.gnu.org/copyleft/lesser.html>.) |
| |
| This library is distributed in the hope that it will be useful, but WITHOUT |
| ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS |
| FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for |
| more details. |
| |
| You should have received a copy of the GNU Lesser General Public License |
| along with this library; if not, write to the Free Software Foundation, Inc., |
| 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| **********/ |
| // "liveMedia" |
| // Copyright (c) 1996-2020 Live Networks, Inc. All rights reserved. |
| // VP9 Video RTP Sources |
| // Implementation |
| |
| #include "VP9VideoRTPSource.hh" |
| |
| VP9VideoRTPSource* |
| VP9VideoRTPSource::createNew(UsageEnvironment& env, Groupsock* RTPgs, |
| unsigned char rtpPayloadFormat, |
| unsigned rtpTimestampFrequency) { |
| return new VP9VideoRTPSource(env, RTPgs, rtpPayloadFormat, |
| rtpTimestampFrequency); |
| } |
| |
| VP9VideoRTPSource |
| ::VP9VideoRTPSource(UsageEnvironment& env, Groupsock* RTPgs, |
| unsigned char rtpPayloadFormat, |
| unsigned rtpTimestampFrequency) |
| : MultiFramedRTPSource(env, RTPgs, rtpPayloadFormat, rtpTimestampFrequency) { |
| } |
| |
| VP9VideoRTPSource::~VP9VideoRTPSource() { |
| } |
| |
| #define incrHeader do { ++resultSpecialHeaderSize; ++headerStart; if (--packetSize == 0) return False; } while (0) |
| |
| Boolean VP9VideoRTPSource |
| ::processSpecialHeader(BufferedPacket* packet, |
| unsigned& resultSpecialHeaderSize) { |
| unsigned char* headerStart = packet->data(); |
| unsigned packetSize = packet->dataSize(); |
| |
| // Figure out the size of the special header. |
| if (packetSize == 0) return False; // error |
| resultSpecialHeaderSize = 1; // unless we learn otherwise |
| |
| u_int8_t const byte1 = *headerStart; |
| Boolean const I = (byte1&0x80) != 0; |
| Boolean const L = (byte1&0x40) != 0; |
| Boolean const F = (byte1&0x20) != 0; |
| Boolean const B = (byte1&0x10) != 0; |
| Boolean const E = (byte1&0x08) != 0; |
| Boolean const V = (byte1&0x04) != 0; |
| Boolean const U = (byte1&0x02) != 0; |
| |
| fCurrentPacketBeginsFrame = B; |
| fCurrentPacketCompletesFrame = E; |
| // use this instead of the RTP header's 'M' bit (which might not be accurate) |
| |
| if (I) { // PictureID present |
| incrHeader; |
| Boolean const M = ((*headerStart)&0x80) != 0; |
| if (M) incrHeader; |
| } |
| |
| if (L) { // Layer indices present |
| incrHeader; |
| if (F) { // Reference indices present |
| incrHeader; |
| unsigned R = (*headerStart)&0x03; |
| while (R-- > 0) { |
| incrHeader; |
| Boolean const X = ((*headerStart)&0x10) != 0; |
| if (X) incrHeader; |
| } |
| } |
| } |
| |
| if (V) { // Scalability Structure (SS) present |
| incrHeader; |
| unsigned patternLength = *headerStart; |
| while (patternLength-- > 0) { |
| incrHeader; |
| unsigned R = (*headerStart)&0x03; |
| while (R-- > 0) { |
| incrHeader; |
| Boolean const X = ((*headerStart)&0x10) != 0; |
| if (X) incrHeader; |
| } |
| } |
| } |
| |
| if (U) { // Scalability Structure Update (SU) present |
| return False; // This structure isn't yet defined in the VP9 payload format I-D |
| } |
| |
| return True; |
| } |
| |
| char const* VP9VideoRTPSource::MIMEtype() const { |
| return "video/VP9"; |
| } |