| /********** |
| 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. |
| // VP8 Video RTP Sources |
| // Implementation |
| |
| #include "VP8VideoRTPSource.hh" |
| |
| VP8VideoRTPSource* |
| VP8VideoRTPSource::createNew(UsageEnvironment& env, Groupsock* RTPgs, |
| unsigned char rtpPayloadFormat, |
| unsigned rtpTimestampFrequency) { |
| return new VP8VideoRTPSource(env, RTPgs, rtpPayloadFormat, |
| rtpTimestampFrequency); |
| } |
| |
| VP8VideoRTPSource |
| ::VP8VideoRTPSource(UsageEnvironment& env, Groupsock* RTPgs, |
| unsigned char rtpPayloadFormat, |
| unsigned rtpTimestampFrequency) |
| : MultiFramedRTPSource(env, RTPgs, rtpPayloadFormat, rtpTimestampFrequency) { |
| } |
| |
| VP8VideoRTPSource::~VP8VideoRTPSource() { |
| } |
| |
| #define incrHeader do { ++resultSpecialHeaderSize; ++headerStart; if (--packetSize == 0) return False; } while (0) |
| |
| Boolean VP8VideoRTPSource |
| ::processSpecialHeader(BufferedPacket* packet, |
| unsigned& resultSpecialHeaderSize) { |
| unsigned char* headerStart = packet->data(); |
| unsigned packetSize = packet->dataSize(); |
| |
| // The special header is from 1 to 6 bytes long. |
| if (packetSize == 0) return False; // error |
| resultSpecialHeaderSize = 1; // unless we learn otherwise |
| |
| u_int8_t const byte1 = *headerStart; |
| Boolean const X = (byte1&0x80) != 0; |
| Boolean const S = (byte1&0x10) != 0; |
| u_int8_t const PartID = byte1&0x0F; |
| |
| fCurrentPacketBeginsFrame = S && PartID == 0; |
| fCurrentPacketCompletesFrame = packet->rtpMarkerBit(); // RTP header's "M" bit |
| |
| if (X) { |
| incrHeader; |
| |
| u_int8_t const byte2 = *headerStart; |
| Boolean const I = (byte2&0x80) != 0; |
| Boolean const L = (byte2&0x40) != 0; |
| Boolean const T = (byte2&0x20) != 0; |
| Boolean const K = (byte2&0x10) != 0; |
| |
| if (I) { |
| incrHeader; |
| if ((*headerStart)&0x80) { // extension flag in the PictureID is set |
| incrHeader; |
| } |
| } |
| |
| if (L) incrHeader; |
| if (T||K) incrHeader; |
| } |
| |
| return True; |
| } |
| |
| char const* VP8VideoRTPSource::MIMEtype() const { |
| return "video/VP8"; |
| } |