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/**********
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 2.1 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.,
59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
**********/
// "liveMedia"
// Copyright (c) 1996-2005 Live Networks, Inc. All rights reserved.
// RTP sink for H.263+ video (RFC 2429)
// Implementation
#include "H263plusVideoRTPSink.hh"
H263plusVideoRTPSink
::H263plusVideoRTPSink(UsageEnvironment& env, Groupsock* RTPgs,
unsigned char rtpPayloadFormat,
u_int32_t rtpTimestampFrequency)
: VideoRTPSink(env, RTPgs, rtpPayloadFormat, rtpTimestampFrequency, "H263-1998"),
fAreInFragmentedFrame(False) {
}
H263plusVideoRTPSink::~H263plusVideoRTPSink() {
}
H263plusVideoRTPSink*
H263plusVideoRTPSink::createNew(UsageEnvironment& env, Groupsock* RTPgs,
unsigned char rtpPayloadFormat,
u_int32_t rtpTimestampFrequency) {
return new H263plusVideoRTPSink(env, RTPgs, rtpPayloadFormat, rtpTimestampFrequency);
}
Boolean H263plusVideoRTPSink
::frameCanAppearAfterPacketStart(unsigned char const* /*frameStart*/,
unsigned /*numBytesInFrame*/) const {
// A packet can contain only one frame
return False;
}
void H263plusVideoRTPSink
::doSpecialFrameHandling(unsigned fragmentationOffset,
unsigned char* frameStart,
unsigned numBytesInFrame,
struct timeval frameTimestamp,
unsigned numRemainingBytes) {
if (fragmentationOffset == 0) {
// This packet contains the first (or only) fragment of the frame.
// Set the 'P' bit in the special header:
unsigned short specialHeader = 0x0400;
// Also, reuse the first two bytes of the payload for this special
// header. (They should both have been zero.)
if (numBytesInFrame < 2) {
envir() << "H263plusVideoRTPSink::doSpecialFrameHandling(): bad frame size "
<< numBytesInFrame << "\n";
return;
}
if (frameStart[0] != 0 || frameStart[1] != 0) {
envir() << "H263plusVideoRTPSink::doSpecialFrameHandling(): unexpected non-zero first two bytes: "
<< (void*)(frameStart[0]) << "," << (void*)(frameStart[1]) << "\n";
}
frameStart[0] = specialHeader>>8;
frameStart[1] = (unsigned char)specialHeader;
} else {
unsigned short specialHeader = 0;
setSpecialHeaderBytes((unsigned char*)&specialHeader, 2);
}
if (numRemainingBytes == 0) {
// This packet contains the last (or only) fragment of the frame.
// Set the RTP 'M' ('marker') bit:
setMarkerBit();
}
fAreInFragmentedFrame = (numRemainingBytes > 0); // for next time
// Also set the RTP timestamp:
setTimestamp(frameTimestamp);
}
unsigned H263plusVideoRTPSink::specialHeaderSize() const {
// There's a 2-byte special video header. However, if we're the first
// (or only) fragment of a frame, then we reuse the first 2 bytes of
// the payload instead.
return fAreInFragmentedFrame ? 2 : 0;
}
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