一段时间以来，我一直在尝试在 Android 上合并两个 WAVE 文件，但似乎无法使其正常工作。
一切看起来都很好，文件被读取并写入输出文件，该文件在稍后阶段也可以读取，并且具有我希望看到的文件大小。
问题在应用程序完成合并后立即出现。此消息将显示在日志中：错误发生在 updateListener,recording is aborted这是一条消息，extAudioRecorder当OnRecordPositionUpdateListener到达 catch 子句时出现（异常有以下 detailMessage: write failed: EBADF (Bad file number)）。这似乎并没有破坏任何东西，所以我不太担心。
当我尝试在 MediaPlayer 实例上创建MediaPlayer和调用时，真正的问题出现了。setDataSource(String path)每当我对合并文件执行此操作时，日志中都会显示以下错误消息：无法创建媒体播放器（IOException抛出的包含以下 detailMessage: setDataSourceFD failed.: status=0x80000000）。请注意，该文件第一次播放会非常好（第一个文件不是由该combineWaveFiles()方法制作的）。该错误消息似乎表明音频文件的格式不正确和/或 MediaPlayer 无法读取。
我的问题是，是否有人看到下面的代码有任何真正的问题（我知道它在很多方面都不是最理想的，但我更喜欢先让它工作，然后再担心性能）。
public static String MergeRecordings(String cumulativeFile, String recordFile, int sampleRate, int bpp, int bufferSize, int channels) {
if (cumulativeFile == null) {
return recordFile;
} else if (recordFile == null) {
return cumulativeFile;
}
String outputFile = FileUtils.getFilePath(null, MDSettings.shared().getMainActivity());
FileUtils.combineWaveFiles(cumulativeFile, recordFile, outputFile, sampleRate, bpp, bufferSize, channels);
//FileUtils.removeFile(cumulativeFile);
//FileUtils.removeFile(recordFile);
return outputFile;
}
//creates a new file containing file1 + file2 stuck together as such.
private static void combineWaveFiles(String file1, String file2, String outputFile, int sampleRate, int bpp, int bufferSize, int channels) {
FileInputStream in1 = null, in2 = null;
FileOutputStream out = null;
long longSampleRate = sampleRate;
long byteRate = sampleRate * channels * bpp / 8;
byte[] data;
try {
try {
in1 = new FileInputStream(file1);
} catch (Exception e) { }
try {
in2 = new FileInputStream(file2);
} catch (FileNotFoundException e) { }
out = new FileOutputStream(outputFile);
long file1Size = 0;
long file2Size = 0;
if (in1 != null) { file1Size = in1.getChannel().size() - 44; }
if (in2 != null) { file2Size = in2.getChannel().size() - 44; }
long totalAudioLen = file1Size + file2Size;
long totalDataLen = totalAudioLen + 36;
FileUtils.writeWaveFileHeader(out, totalAudioLen, totalDataLen, longSampleRate, channels, byteRate, bpp);
if (in1 != null) {
in1.skip(44);
data = new byte[bufferSize];
if (file1Size < bufferSize) {
data = new byte[(int)file1Size];
}
while (in1.read(data) != -1) {
out.write(data);
file1Size -= bufferSize;
if (file1Size <= 0) {
break;
} else if (file1Size < bufferSize) {
data = new byte[(int)file1Size];
}
}
}
if (in2 != null) {
in2.skip(44);
data = new byte[bufferSize];
if (file2Size < bufferSize) {
data = new byte[(int)file2Size];
}
while (in2.read(data) != -1) {
out.write(data);
file2Size -= bufferSize;
if (file2Size <= 0) {
break;
} else if (file2Size < bufferSize) {
data = new byte[(int)file2Size];
}
}
}
out.close();
if (in1 != null) { in1.close(); }
if (in2 != null) { in2.close(); }
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
private static void writeWaveFileHeader(FileOutputStream out, long totalAudioLen, long totalDataLen, long longSampleRate, int channels, long byteRate, int bpp)
throws IOException {
byte[] header = new byte[44];
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';
header[13] = 'm';
header[14] = 't';
header[15] = ' ';
header[16] = 16;
header[17] = 0;
header[18] = 0;
header[19] = 0;
header[20] = 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)(channels * bpp); //(2 * 16 / 8);
header[33] = 0;
header[34] = (byte)bpp;
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);
out.write(header, 0, 44);
}
此代码的大部分内容来自此答案。