Moving src/webrtc into src/.
In order to eliminate the WebRTC Subtree mirror in Chromium, WebRTC is moving the content of the src/webrtc directory up to the src/ directory. NOPRESUBMIT=true NOTREECHECKS=true NOTRY=true TBR=tommi@webrtc.org Bug: chromium:611808 Change-Id: Iac59c5b51b950f174119565bac87955a7994bc38 Reviewed-on: https://webrtc-review.googlesource.com/1560 Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org> Reviewed-by: Henrik Kjellander <kjellander@webrtc.org> Cr-Commit-Position: refs/heads/master@{#19845}
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497
modules/rtp_rtcp/source/rtp_utility.cc
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497
modules/rtp_rtcp/source/rtp_utility.cc
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@ -0,0 +1,497 @@
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/*
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* Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
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*
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* Use of this source code is governed by a BSD-style license
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* that can be found in the LICENSE file in the root of the source
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* tree. An additional intellectual property rights grant can be found
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* in the file PATENTS. All contributing project authors may
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* be found in the AUTHORS file in the root of the source tree.
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*/
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#include "webrtc/modules/rtp_rtcp/source/rtp_utility.h"
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#include "webrtc/modules/rtp_rtcp/include/rtp_cvo.h"
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#include "webrtc/modules/rtp_rtcp/source/byte_io.h"
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#include "webrtc/modules/rtp_rtcp/source/rtp_header_extensions.h"
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#include "webrtc/rtc_base/logging.h"
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namespace webrtc {
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RtpFeedback* NullObjectRtpFeedback() {
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static NullRtpFeedback null_rtp_feedback;
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return &null_rtp_feedback;
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}
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namespace RtpUtility {
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enum {
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kRtcpExpectedVersion = 2,
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kRtcpMinHeaderLength = 4,
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kRtcpMinParseLength = 8,
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kRtpExpectedVersion = 2,
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kRtpMinParseLength = 12
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};
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/*
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* Misc utility routines
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*/
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#if defined(_WIN32)
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bool StringCompare(const char* str1, const char* str2,
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const uint32_t length) {
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return _strnicmp(str1, str2, length) == 0;
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}
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#elif defined(WEBRTC_LINUX) || defined(WEBRTC_MAC)
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bool StringCompare(const char* str1, const char* str2,
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const uint32_t length) {
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return strncasecmp(str1, str2, length) == 0;
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}
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#endif
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size_t Word32Align(size_t size) {
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uint32_t remainder = size % 4;
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if (remainder != 0)
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return size + 4 - remainder;
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return size;
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}
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RtpHeaderParser::RtpHeaderParser(const uint8_t* rtpData,
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const size_t rtpDataLength)
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: _ptrRTPDataBegin(rtpData),
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_ptrRTPDataEnd(rtpData ? (rtpData + rtpDataLength) : NULL) {
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}
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RtpHeaderParser::~RtpHeaderParser() {
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}
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bool RtpHeaderParser::RTCP() const {
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// 72 to 76 is reserved for RTP
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// 77 to 79 is not reserver but they are not assigned we will block them
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// for RTCP 200 SR == marker bit + 72
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// for RTCP 204 APP == marker bit + 76
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/*
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* RTCP
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*
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* FIR full INTRA-frame request 192 [RFC2032] supported
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* NACK negative acknowledgement 193 [RFC2032]
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* IJ Extended inter-arrival jitter report 195 [RFC-ietf-avt-rtp-toff
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* set-07.txt] http://tools.ietf.org/html/draft-ietf-avt-rtp-toffset-07
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* SR sender report 200 [RFC3551] supported
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* RR receiver report 201 [RFC3551] supported
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* SDES source description 202 [RFC3551] supported
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* BYE goodbye 203 [RFC3551] supported
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* APP application-defined 204 [RFC3551] ignored
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* RTPFB Transport layer FB message 205 [RFC4585] supported
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* PSFB Payload-specific FB message 206 [RFC4585] supported
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* XR extended report 207 [RFC3611] supported
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*/
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/* 205 RFC 5104
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* FMT 1 NACK supported
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* FMT 2 reserved
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* FMT 3 TMMBR supported
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* FMT 4 TMMBN supported
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*/
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/* 206 RFC 5104
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* FMT 1: Picture Loss Indication (PLI) supported
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* FMT 2: Slice Lost Indication (SLI)
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* FMT 3: Reference Picture Selection Indication (RPSI)
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* FMT 4: Full Intra Request (FIR) Command supported
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* FMT 5: Temporal-Spatial Trade-off Request (TSTR)
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* FMT 6: Temporal-Spatial Trade-off Notification (TSTN)
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* FMT 7: Video Back Channel Message (VBCM)
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* FMT 15: Application layer FB message
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*/
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const ptrdiff_t length = _ptrRTPDataEnd - _ptrRTPDataBegin;
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if (length < kRtcpMinHeaderLength) {
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return false;
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}
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const uint8_t V = _ptrRTPDataBegin[0] >> 6;
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if (V != kRtcpExpectedVersion) {
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return false;
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}
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const uint8_t payloadType = _ptrRTPDataBegin[1];
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switch (payloadType) {
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case 192:
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return true;
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case 193:
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// not supported
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// pass through and check for a potential RTP packet
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return false;
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case 195:
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case 200:
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case 201:
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case 202:
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case 203:
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case 204:
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case 205:
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case 206:
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case 207:
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return true;
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default:
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return false;
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}
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}
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bool RtpHeaderParser::ParseRtcp(RTPHeader* header) const {
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assert(header != NULL);
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const ptrdiff_t length = _ptrRTPDataEnd - _ptrRTPDataBegin;
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if (length < kRtcpMinParseLength) {
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return false;
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}
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const uint8_t V = _ptrRTPDataBegin[0] >> 6;
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if (V != kRtcpExpectedVersion) {
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return false;
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}
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const uint8_t PT = _ptrRTPDataBegin[1];
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const size_t len = (_ptrRTPDataBegin[2] << 8) + _ptrRTPDataBegin[3];
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const uint8_t* ptr = &_ptrRTPDataBegin[4];
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uint32_t SSRC = ByteReader<uint32_t>::ReadBigEndian(ptr);
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ptr += 4;
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header->payloadType = PT;
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header->ssrc = SSRC;
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header->headerLength = 4 + (len << 2);
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return true;
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}
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bool RtpHeaderParser::Parse(RTPHeader* header,
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RtpHeaderExtensionMap* ptrExtensionMap) const {
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const ptrdiff_t length = _ptrRTPDataEnd - _ptrRTPDataBegin;
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if (length < kRtpMinParseLength) {
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return false;
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}
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// Version
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const uint8_t V = _ptrRTPDataBegin[0] >> 6;
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// Padding
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const bool P = ((_ptrRTPDataBegin[0] & 0x20) == 0) ? false : true;
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// eXtension
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const bool X = ((_ptrRTPDataBegin[0] & 0x10) == 0) ? false : true;
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const uint8_t CC = _ptrRTPDataBegin[0] & 0x0f;
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const bool M = ((_ptrRTPDataBegin[1] & 0x80) == 0) ? false : true;
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const uint8_t PT = _ptrRTPDataBegin[1] & 0x7f;
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const uint16_t sequenceNumber = (_ptrRTPDataBegin[2] << 8) +
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_ptrRTPDataBegin[3];
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const uint8_t* ptr = &_ptrRTPDataBegin[4];
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uint32_t RTPTimestamp = ByteReader<uint32_t>::ReadBigEndian(ptr);
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ptr += 4;
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uint32_t SSRC = ByteReader<uint32_t>::ReadBigEndian(ptr);
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ptr += 4;
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if (V != kRtpExpectedVersion) {
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return false;
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}
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const size_t CSRCocts = CC * 4;
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if ((ptr + CSRCocts) > _ptrRTPDataEnd) {
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return false;
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}
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header->markerBit = M;
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header->payloadType = PT;
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header->sequenceNumber = sequenceNumber;
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header->timestamp = RTPTimestamp;
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header->ssrc = SSRC;
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header->numCSRCs = CC;
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header->paddingLength = P ? *(_ptrRTPDataEnd - 1) : 0;
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for (uint8_t i = 0; i < CC; ++i) {
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uint32_t CSRC = ByteReader<uint32_t>::ReadBigEndian(ptr);
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ptr += 4;
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header->arrOfCSRCs[i] = CSRC;
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}
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header->headerLength = 12 + CSRCocts;
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// If in effect, MAY be omitted for those packets for which the offset
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// is zero.
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header->extension.hasTransmissionTimeOffset = false;
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header->extension.transmissionTimeOffset = 0;
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// May not be present in packet.
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header->extension.hasAbsoluteSendTime = false;
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header->extension.absoluteSendTime = 0;
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// May not be present in packet.
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header->extension.hasAudioLevel = false;
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header->extension.voiceActivity = false;
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header->extension.audioLevel = 0;
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// May not be present in packet.
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header->extension.hasVideoRotation = false;
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header->extension.videoRotation = kVideoRotation_0;
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// May not be present in packet.
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header->extension.playout_delay.min_ms = -1;
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header->extension.playout_delay.max_ms = -1;
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// May not be present in packet.
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header->extension.hasVideoContentType = false;
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header->extension.videoContentType = VideoContentType::UNSPECIFIED;
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header->extension.has_video_timing = false;
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header->extension.video_timing = {0u, 0u, 0u, 0u, 0u, 0u, false};
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if (X) {
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/* RTP header extension, RFC 3550.
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0 1 2 3
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0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
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+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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| defined by profile | length |
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+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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| header extension |
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| .... |
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*/
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const ptrdiff_t remain = _ptrRTPDataEnd - ptr;
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if (remain < 4) {
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return false;
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}
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header->headerLength += 4;
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uint16_t definedByProfile = ByteReader<uint16_t>::ReadBigEndian(ptr);
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ptr += 2;
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// in 32 bit words
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size_t XLen = ByteReader<uint16_t>::ReadBigEndian(ptr);
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ptr += 2;
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XLen *= 4; // in bytes
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if (static_cast<size_t>(remain) < (4 + XLen)) {
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return false;
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}
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static constexpr uint16_t kRtpOneByteHeaderExtensionId = 0xBEDE;
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if (definedByProfile == kRtpOneByteHeaderExtensionId) {
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const uint8_t* ptrRTPDataExtensionEnd = ptr + XLen;
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ParseOneByteExtensionHeader(header,
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ptrExtensionMap,
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ptrRTPDataExtensionEnd,
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ptr);
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}
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header->headerLength += XLen;
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}
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if (header->headerLength + header->paddingLength >
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static_cast<size_t>(length))
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return false;
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return true;
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}
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void RtpHeaderParser::ParseOneByteExtensionHeader(
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RTPHeader* header,
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const RtpHeaderExtensionMap* ptrExtensionMap,
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const uint8_t* ptrRTPDataExtensionEnd,
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const uint8_t* ptr) const {
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if (!ptrExtensionMap) {
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return;
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}
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while (ptrRTPDataExtensionEnd - ptr > 0) {
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// 0
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// 0 1 2 3 4 5 6 7
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// +-+-+-+-+-+-+-+-+
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// | ID | len |
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// +-+-+-+-+-+-+-+-+
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// Note that 'len' is the header extension element length, which is the
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// number of bytes - 1.
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const int id = (*ptr & 0xf0) >> 4;
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const int len = (*ptr & 0x0f);
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ptr++;
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if (id == 0) {
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// Padding byte, skip ignoring len.
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continue;
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}
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if (id == 15) {
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LOG(LS_VERBOSE)
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<< "RTP extension header 15 encountered. Terminate parsing.";
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return;
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}
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if (ptrRTPDataExtensionEnd - ptr < (len + 1)) {
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LOG(LS_WARNING) << "Incorrect one-byte extension len: " << (len + 1)
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<< ", bytes left in buffer: "
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<< (ptrRTPDataExtensionEnd - ptr);
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return;
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}
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RTPExtensionType type = ptrExtensionMap->GetType(id);
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if (type == RtpHeaderExtensionMap::kInvalidType) {
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// If we encounter an unknown extension, just skip over it.
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LOG(LS_WARNING) << "Failed to find extension id: " << id;
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} else {
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switch (type) {
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case kRtpExtensionTransmissionTimeOffset: {
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if (len != 2) {
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LOG(LS_WARNING) << "Incorrect transmission time offset len: "
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<< len;
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return;
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}
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// 0 1 2 3
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// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
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// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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// | ID | len=2 | transmission offset |
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// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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header->extension.transmissionTimeOffset =
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ByteReader<int32_t, 3>::ReadBigEndian(ptr);
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header->extension.hasTransmissionTimeOffset = true;
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break;
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}
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case kRtpExtensionAudioLevel: {
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if (len != 0) {
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LOG(LS_WARNING) << "Incorrect audio level len: " << len;
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return;
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}
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// 0 1
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// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
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// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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// | ID | len=0 |V| level |
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// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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//
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header->extension.audioLevel = ptr[0] & 0x7f;
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header->extension.voiceActivity = (ptr[0] & 0x80) != 0;
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header->extension.hasAudioLevel = true;
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break;
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}
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case kRtpExtensionAbsoluteSendTime: {
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if (len != 2) {
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LOG(LS_WARNING) << "Incorrect absolute send time len: " << len;
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return;
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}
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// 0 1 2 3
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// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
|
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// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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// | ID | len=2 | absolute send time |
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// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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header->extension.absoluteSendTime =
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ByteReader<uint32_t, 3>::ReadBigEndian(ptr);
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header->extension.hasAbsoluteSendTime = true;
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break;
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}
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case kRtpExtensionVideoRotation: {
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if (len != 0) {
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LOG(LS_WARNING)
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<< "Incorrect coordination of video coordination len: " << len;
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return;
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}
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||||
// 0 1
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// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
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// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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// | ID | len=0 |0 0 0 0 C F R R|
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// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
||||
header->extension.hasVideoRotation = true;
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header->extension.videoRotation =
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ConvertCVOByteToVideoRotation(ptr[0]);
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||||
break;
|
||||
}
|
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case kRtpExtensionTransportSequenceNumber: {
|
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if (len != 1) {
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LOG(LS_WARNING) << "Incorrect transport sequence number len: "
|
||||
<< len;
|
||||
return;
|
||||
}
|
||||
// 0 1 2
|
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// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
|
||||
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
||||
// | ID | L=1 |transport wide sequence number |
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||||
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
||||
|
||||
uint16_t sequence_number = ptr[0] << 8;
|
||||
sequence_number += ptr[1];
|
||||
header->extension.transportSequenceNumber = sequence_number;
|
||||
header->extension.hasTransportSequenceNumber = true;
|
||||
break;
|
||||
}
|
||||
case kRtpExtensionPlayoutDelay: {
|
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if (len != 2) {
|
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LOG(LS_WARNING) << "Incorrect playout delay len: " << len;
|
||||
return;
|
||||
}
|
||||
// 0 1 2 3
|
||||
// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
|
||||
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
||||
// | ID | len=2 | MIN delay | MAX delay |
|
||||
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
||||
|
||||
int min_playout_delay = (ptr[0] << 4) | ((ptr[1] >> 4) & 0xf);
|
||||
int max_playout_delay = ((ptr[1] & 0xf) << 8) | ptr[2];
|
||||
header->extension.playout_delay.min_ms =
|
||||
min_playout_delay * PlayoutDelayLimits::kGranularityMs;
|
||||
header->extension.playout_delay.max_ms =
|
||||
max_playout_delay * PlayoutDelayLimits::kGranularityMs;
|
||||
break;
|
||||
}
|
||||
case kRtpExtensionVideoContentType: {
|
||||
if (len != 0) {
|
||||
LOG(LS_WARNING) << "Incorrect video content type len: " << len;
|
||||
return;
|
||||
}
|
||||
// 0 1
|
||||
// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
|
||||
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
||||
// | ID | len=0 | Content type |
|
||||
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
||||
|
||||
if (videocontenttypehelpers::IsValidContentType(ptr[0])) {
|
||||
header->extension.hasVideoContentType = true;
|
||||
header->extension.videoContentType =
|
||||
static_cast<VideoContentType>(ptr[0]);
|
||||
}
|
||||
break;
|
||||
}
|
||||
case kRtpExtensionVideoTiming: {
|
||||
if (len != VideoTimingExtension::kValueSizeBytes - 1) {
|
||||
LOG(LS_WARNING) << "Incorrect video timing len: " << len;
|
||||
return;
|
||||
}
|
||||
header->extension.has_video_timing = true;
|
||||
VideoTimingExtension::Parse(rtc::MakeArrayView(ptr, len + 1),
|
||||
&header->extension.video_timing);
|
||||
break;
|
||||
}
|
||||
case kRtpExtensionRtpStreamId: {
|
||||
header->extension.stream_id.Set(rtc::MakeArrayView(ptr, len + 1));
|
||||
break;
|
||||
}
|
||||
case kRtpExtensionRepairedRtpStreamId: {
|
||||
header->extension.repaired_stream_id.Set(
|
||||
rtc::MakeArrayView(ptr, len + 1));
|
||||
break;
|
||||
}
|
||||
case kRtpExtensionMid: {
|
||||
header->extension.mid.Set(rtc::MakeArrayView(ptr, len + 1));
|
||||
break;
|
||||
}
|
||||
case kRtpExtensionNone:
|
||||
case kRtpExtensionNumberOfExtensions: {
|
||||
RTC_NOTREACHED() << "Invalid extension type: " << type;
|
||||
return;
|
||||
}
|
||||
}
|
||||
}
|
||||
ptr += (len + 1);
|
||||
}
|
||||
}
|
||||
|
||||
} // namespace RtpUtility
|
||||
} // namespace webrtc
|
||||
Reference in New Issue
Block a user