mpeg2transportfileservermediasubsession.cpp

流媒体传输协议的实现代码,非常有用.可以支持rtsp mms等流媒体传输协议

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FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for
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// "liveMedia"
// Copyright (c) 1996-2004 Live Networks, Inc.  All rights reserved.
// A 'ServerMediaSubsession' object that creates new, unicast, "RTPSink"s
// on demand, from a MPEG-2 Transport Stream file.
// Implementation

#include "MPEG2TransportFileServerMediaSubsession.hh"
#include "SimpleRTPSink.hh"
#include "ByteStreamFileSource.hh"
#include "MPEG2TransportStreamFramer.hh"

MPEG2TransportFileServerMediaSubsession*
MPEG2TransportFileServerMediaSubsession::createNew(UsageEnvironment& env,
						   char const* fileName,
						   Boolean reuseFirstSource) {
  return new MPEG2TransportFileServerMediaSubsession(env, fileName, reuseFirstSource);
}

MPEG2TransportFileServerMediaSubsession
::MPEG2TransportFileServerMediaSubsession(UsageEnvironment& env,
                                      char const* fileName, Boolean reuseFirstSource)
  : FileServerMediaSubsession(env, fileName, reuseFirstSource) {
}

MPEG2TransportFileServerMediaSubsession
::~MPEG2TransportFileServerMediaSubsession() {
}

#define TRANSPORT_PACKET_SIZE 188
#define TRANSPORT_PACKETS_PER_NETWORK_PACKET 7
// The product of these two numbers must be enough to fit within a network packet

FramedSource* MPEG2TransportFileServerMediaSubsession
::createNewStreamSource(unsigned /*clientSessionId*/, unsigned& estBitrate) {
  estBitrate = 5000; // kbps, estimate

  // Create the video source:
  unsigned const inputDataChunkSize
    = TRANSPORT_PACKETS_PER_NETWORK_PACKET*TRANSPORT_PACKET_SIZE;
  ByteStreamFileSource* fileSource
    = ByteStreamFileSource::createNew(envir(), fFileName, inputDataChunkSize);
  if (fileSource == NULL) return NULL;
  fFileSize = fileSource->fileSize();

  // Create a framer for the Transport Stream:
  return MPEG2TransportStreamFramer::createNew(envir(), fileSource);
}

RTPSink* MPEG2TransportFileServerMediaSubsession
::createNewRTPSink(Groupsock* rtpGroupsock,
		   unsigned char /*rtpPayloadTypeIfDynamic*/,
		   FramedSource* /*inputSource*/) {
  return SimpleRTPSink::createNew(envir(), rtpGroupsock,
				  33, 90000, "video", "mp2t",
				  1, True, False /*no 'M' bit*/);
}