mp3transcoder.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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// "liveMedia"
// Copyright (c) 1996-2004 Live Networks, Inc.  All rights reserved.
// MP3 Transcoder
// Implementation

#include "MP3Transcoder.hh"

MP3Transcoder::MP3Transcoder(UsageEnvironment& env,
			     MP3ADUTranscoder* aduTranscoder)
  : MP3FromADUSource(env, aduTranscoder, False) {
}

MP3Transcoder::~MP3Transcoder() {
}

MP3Transcoder* MP3Transcoder::createNew(UsageEnvironment& env,
					unsigned outBitrate /* in kbps */,
					FramedSource* inputSource) {
  MP3Transcoder* newSource = NULL;

  do {
    // Create the intermediate filters that help implement the transcoder:
    ADUFromMP3Source* aduFromMP3
      = ADUFromMP3Source::createNew(env, inputSource, False);
    // Note: This also checks that "inputSource" is an MP3 source
    if (aduFromMP3 == NULL) break;

    MP3ADUTranscoder* aduTranscoder
      = MP3ADUTranscoder::createNew(env, outBitrate, aduFromMP3);
    if (aduTranscoder == NULL) break;

    // Then create the transcoder itself:
    newSource = new MP3Transcoder(env, aduTranscoder);
  } while (0);

  return newSource;
}