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我有一些关于 Xuggler API 的问题，

我想创建一个小类，一旦打开一个 mp3 文件，它就会从中获取原始字节，但是，有多少？我想从原始文件中获取 1 秒的样本。

这是我当前的代码：

public byte[] getSamples(int iBytesQtty){
    byte[] rawBytes = null;

    /** Go to the correct packet */
    while (this._inputContainer.readNextPacket(this._packet) >= 0){
        System.out.println(this._packet.getDuration());
        /** Once we have a packet, let's see if it belongs to the audio stream */

        if (this._packet.getStreamIndex() == this._iAudioStreamId){
            IAudioSamples samples = IAudioSamples.make(iBytesQtty, this._audioCoder.getChannels());


            //System.out.println(">> " + samples.toString());
            /** Because a packet can contain multiple set of samples (frames of samples). We may need to call
             * decode audio multiple times at different offsets in the packet's data */

            int iCurrentOffset = 0;

            while(iCurrentOffset < this._packet.getSize()){

                int iBytesDecoded = this._audioCoder.decodeAudio(samples, this._packet, iCurrentOffset);
                iCurrentOffset += iBytesDecoded;

                if (samples.isComplete()){
                    rawBytes = samples.getData().getByteArray(0, samples.getSize());
                }
            }
            return rawBytes;
        }
        else{
            /** Otherwise drop it */
            do{}while(false); /** WTF? **/
        }
    }
    return rawBytes; /** This will return null at this point */
}

任何提示将不胜感激，在此先感谢。

编辑：

实际上，这段小代码对我有用，但并非在所有情况下

Mp3File song = new Mp3File("sample.mp3");
        byte[] buff = null;
        int totalBytes = 0;
int iNumBytes = 1024;

        while( (buff = song.getSamples(iNumBytes)) != null ){
            totalBytes += buff.length;
    //      System.out.println("Length buff: " + buff.length + " TOTAL: " + totalBytes);
        }

System.out.println("Bytes: " + totalBytes + " (" + totalBytes/1024 + " Kb.)");
        float lengthSecs = (float) (totalBytes / ((1411*1000)/8)); 
        float lengthMins = lengthSecs/60;

        System.out.println("song duration: " + lengthMins + " mins. (" + lengthSecs + " secs.)");

我假设它实际上在内部转换为常规 WAV 文件的 mp3 文件，所以每秒我有 1411kbps 的速率。但正如我所说，它并不适用于所有情况。

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