Java File Read via ByteBuffer readWavHeader(DataInputStream inStrm, FileChannel fc)

Description

read Wav Header

License

Open Source License

Declaration

private static boolean readWavHeader(DataInputStream inStrm, FileChannel fc) 

Method Source Code

//package com.java2s;

import java.io.DataInputStream;

import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;

import java.nio.channels.FileChannel;

public class Main {
    public static int srcChannels, dstChannels, srcBPS;
    public static int srcSamplingRate, dstSamplingRate, dstBPS;
    public static long length = 0;

    private static boolean readWavHeader(DataInputStream inStrm, FileChannel fc) {
        byte[] buf = new byte[16];
        int size;
        ByteBuffer bb = ByteBuffer.wrap(buf).order(ByteOrder.LITTLE_ENDIAN);
        bb.clear();/*w  w  w  .  j  a v  a 2s  . co m*/
        try {
            inStrm.readInt();

            inStrm.readFully(buf, 0, 8);
            if (!"WAVEfmt ".equals(new String(buf, 0, 8)))
                return false;

            inStrm.readFully(buf, 0, 4);
            size = bb.getInt();
            if (size > buf.length) {
                buf = new byte[size];
                bb = ByteBuffer.wrap(buf).order(ByteOrder.LITTLE_ENDIAN);
            }
            inStrm.readFully(buf, 0, size);
            bb.clear();

            if (bb.getShort() != 1) {
                System.err.println(String.format("Error: Only PCM is supported."));
                return false;
            }
            srcChannels = bb.getShort();
            srcSamplingRate = bb.getInt();
            srcBPS = bb.getInt();
            if ((int) srcBPS % srcSamplingRate * srcChannels != 0)
                return false;

            srcBPS /= srcSamplingRate * srcChannels;

            byte[] cbuf = new byte[4];
            for (;;) {
                inStrm.readFully(cbuf, 0, 4);
                try {
                    bb.clear();
                    inStrm.readFully(buf, 0, 4);
                    length = (long) bb.getInt();
                } catch (IOException ex) {
                    break;
                }
                if ("data".equals(new String(cbuf, 0, 4)))
                    break;
                fc.position(fc.position() + length);
            }
            if (fc.position() > fc.size()) {
                System.err.println(String.format("Couldn't find data chank"));
                return false;
            }

            if (srcBPS != 1 && srcBPS != 2 && srcBPS != 3 && srcBPS != 4) {
                System.err.println(String.format("Error : Only 8bit, 16bit, 24bit and 32bit PCM are supported."));
                return false;
            }

        } catch (IOException e1) {
            System.err.println("Error reading file header");
            return false;
        }
        return true;
    }
}

Related

1. readUnsignedInt(InputStream is)
2. readUnsignedInt24(InputStream is)
3. readUtf8(DataInput in)
4. readVarLong(byte[] arr)
5. readWaveFile44100_16Bit_Mono(String dir, String name)
6. readWholeFile(File file, StringBuilder stringBuilder)
7. readZipComment(File file)
8. skip(final ReadableByteChannel input, final long toSkip)
9. streamRead(SocketChannel in)