Question

我从wav文件中获取数据，并希望将字节写回wav。

我已经从wav获得了字节。这是我的代码

我知道0-43个字节是标题，44-是数据

byte[] soundBytes;
        try {
            InputStream inputStream = new FileInputStream(getRealPathFromURI(this,uri));
            soundBytes = toByteArray(inputStream);
            for (int i = 0; i != -1 ; i++) {

                if(soundBytes[i]<0) {
                    k =soundBytes[i] + 256;
                } else {k = soundBytes[i];}
                System.out.println("byte " + i + ": " + k );
            }
        } catch(Exception e) {
            e.printStackTrace();
        }


    }
}

public byte[] toByteArray(InputStream in) throws IOException {
    ByteArrayOutputStream out = new ByteArrayOutputStream();
    int read = 0;
    byte[] buffer = new byte[1024];
    while (read != -1) {
        read = in.read(buffer);
        if (read != -1)
            out.write(buffer,0,read);
    }
    out.close();
    return out.toByteArray();
}

Answer 1

以下代码将原始pcm文件转换为原始文件。如你所说，你得到了原始字节，你要么创建一个包含这些字节的原始文件，然后将该文件发送到以下rawToWave（）方法或者操作rawToWave（）方法，以便将require bytes []直接转换为原始文件。

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));
    }
}

android如何将字节写入wav文件

1 个答案: