Android - wav文件播放快

Question

我錄製了從mic到sample.wav的輸入。但它發揮得太快。在3秒內10秒的文件。

int RECORDER_SAMPLERATE = 44100; 
int RECORDER_BitsPerSample = 16; 
int RECORDER_CHANNELS = AudioFormat.CHANNEL_IN_MONO; 
int RECORDER_AUDIO_ENCODING = AudioFormat.ENCODING_PCM_16BIT; 

int channels = 2; 
long byteRate = RECORDER_BPP * RECORDER_SAMPLERATE * channels/8; 

請說明它出錯的地方。

byteRate用於創建wav文件頭。

WAV標題格式是// RIFF/WAVE頭

  header[0] = 'R'; 
    header[1] = 'I'; 
    header[2] = 'F'; 
    header[3] = 'F'; 
    header[4] = (byte) (totalDataLen & 0xff); 
    header[5] = (byte) ((totalDataLen >> 8) & 0xff); 
    header[6] = (byte) ((totalDataLen >> 16) & 0xff); 
    header[7] = (byte) ((totalDataLen >> 24) & 0xff); 
    header[8] = 'W'; 
    header[9] = 'A'; 
    header[10] = 'V'; 
    header[11] = 'E'; 
    header[12] = 'f'; // 'fmt ' chunk 
    header[13] = 'm'; 
    header[14] = 't'; 
    header[15] = ' '; 
    header[16] = 16; // 4 bytes: size of 'fmt ' chunk 
    header[17] = 0; 
    header[18] = 0; 
    header[19] = 0; 
    header[20] = 1; // format = 1 
    header[21] = 0; 
    header[22] = (byte) channels; 
    header[23] = 0; 
    header[24] = (byte) (longSampleRate & 0xff); 
    header[25] = (byte) ((longSampleRate >> 8) & 0xff); 
    header[26] = (byte) ((longSampleRate >> 16) & 0xff); 
    header[27] = (byte) ((longSampleRate >> 24) & 0xff); 
    header[28] = (byte) (byteRate & 0xff); 
    header[29] = (byte) ((byteRate >> 8) & 0xff); 
    header[30] = (byte) ((byteRate >> 16) & 0xff); 
    header[31] = (byte) ((byteRate >> 24) & 0xff); 
    header[32] = (byte) (2 * 16/8); // block align 
    header[33] = 0; 
    header[34] = RECORDER_BPP; // bits per sample 
    header[35] = 0; 
    header[36] = 'd'; 
    header[37] = 'a'; 
    header[38] = 't'; 
    header[39] = 'a'; 
    header[40] = (byte) (totalAudioLen & 0xff); 
    header[41] = (byte) ((totalAudioLen >> 8) & 0xff); 
    header[42] = (byte) ((totalAudioLen >> 16) & 0xff); 
    header[43] = (byte) ((totalAudioLen >> 24) & 0xff); 

Answer 1

我發現上述問題的解決方案。對於AudioFormat.CHANNEL_IN_MONO，通道必須是1。AudioFormat.CHANNEL_IN_STEREO，通道必須是2

int channels = 1; 
long byteRate = RECORDER_BPP * RECORDER_SAMPLERATE * channels/8; 

現在它工作正常。