下面的代碼轉換原始的PCM文件轉換成原始文件。正如你所說的,你得到了原始字節,你可以使用這些字節創建一個原始文件,並將該文件發送到下面的rawToWave()方法或操作rawToWave()方法,以便直接將需要轉換的字節[]轉換爲原始文件。
public void rawToWave(final File rawFile) throws IOException {
File waveFile = DirectoryOperations.createDirAndAudioFile("vocal.wav");// creating the empty wav file.
byte[] rawData = new byte[(int) rawFile.length()];
DataInputStream input = null;
try {
input = new DataInputStream(new FileInputStream(rawFile));
input.read(rawData);
} finally {
if (input != null) {
input.close();
}
}
DataOutputStream output = null;//following block is converting raw to wav.
try {
output = new DataOutputStream(new FileOutputStream(waveFile));
// WAVE header
// see http://ccrma.stanford.edu/courses/422/projects/WaveFormat/
writeString(output, "RIFF"); // chunk id
writeInt(output, 36 + rawData.length); // chunk size
writeString(output, "WAVE"); // format
writeString(output, "fmt "); // subchunk 1 id
writeInt(output, 16); // subchunk 1 size
writeShort(output, (short) 1); // audio format (1 = PCM)
writeShort(output, (short) 1); // number of channels
writeInt(output, RECORDER_SAMPLERATE); // sample rate
writeInt(output, RECORDER_SAMPLERATE * 2); // byte rate
writeShort(output, (short) 2); // block align
writeShort(output, (short) 16); // bits per sample
writeString(output, "data"); // subchunk 2 id
writeInt(output, rawData.length); // subchunk 2 size
output.write(fullyReadFileToBytes(rawFile));
} finally {
if (output != null) {
output.close();
}
}
}
private byte[] fullyReadFileToBytes(File f) throws IOException {
int size = (int) f.length();
byte bytes[] = new byte[size];
byte tmpBuff[] = new byte[size];
try (FileInputStream fis = new FileInputStream(f)) {
int read = fis.read(bytes, 0, size);
if (read < size) {
int remain = size - read;
while (remain > 0) {
read = fis.read(tmpBuff, 0, remain);
System.arraycopy(tmpBuff, 0, bytes, size - remain, read);
remain -= read;
}
}
}
return bytes;
}
private void writeInt(final DataOutputStream output, final int value) throws IOException {
output.write(value);
output.write(value >> 8);
output.write(value >> 16);
output.write(value >> 24);
}
private void writeShort(final DataOutputStream output, final short value) throws IOException {
output.write(value);
output.write(value >> 8);
}
private void writeString(final DataOutputStream output, final String value) throws IOException {
for (int i = 0; i < value.length(); i++) {
output.write(value.charAt(i));
}
}
我很困惑Android是否實現Java類TargetDataLine。如果是的話,這個類將處理所有的.wav頭文件/格式,你所要做的就是提供按照格式轉換成字節的PCM。但我不清楚Android使用多少Java音頻。 –