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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) 1996-2004 Live Networks, Inc. All rights reserved.
// RTP sink for MPEG audio (RFC 2250)
// Implementation
#include "MPEG1or2AudioRTPSink.hh"
MPEG1or2AudioRTPSink::MPEG1or2AudioRTPSink(UsageEnvironment& env, Groupsock* RTPgs)
: AudioRTPSink(env, RTPgs, 14, 90000, "MPA") {
}
MPEG1or2AudioRTPSink::~MPEG1or2AudioRTPSink() {
}
MPEG1or2AudioRTPSink*
MPEG1or2AudioRTPSink::createNew(UsageEnvironment& env, Groupsock* RTPgs) {
return new MPEG1or2AudioRTPSink(env, RTPgs);
}
void MPEG1or2AudioRTPSink::doSpecialFrameHandling(unsigned fragmentationOffset,
unsigned char* frameStart,
unsigned numBytesInFrame,
struct timeval frameTimestamp,
unsigned numRemainingBytes) {
// If this is the 1st frame in the 1st packet, set the RTP 'M' (marker)
// bit (because this is considered the start of a talk spurt):
if (isFirstPacket() && isFirstFrameInPacket()) {
setMarkerBit();
}
// If this is the first frame in the packet, set the lower half of the
// audio-specific header (to the "fragmentationOffset"):
if (isFirstFrameInPacket()) {
setSpecialHeaderWord(fragmentationOffset&0xFFFF);
}
// Important: Also call our base class's doSpecialFrameHandling(),
// to set the packet's timestamp:
MultiFramedRTPSink::doSpecialFrameHandling(fragmentationOffset,
frameStart, numBytesInFrame,
frameTimestamp,
numRemainingBytes);
}
unsigned MPEG1or2AudioRTPSink::specialHeaderSize() const {
// There's a 4 byte special audio header:
return 4;
}
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