Video Steganography in java

问题

I am implementing a video steganography for my project. I came across the algorithm from here . i have tried and tested the code and the embedding part is working fine. But i encountered a problem with the readByte which is the last method in the VideoSteganography class. The method Gives ArrayIndexOutOfBoundsException . Below is the method.

I pass the parameters as

    String fname = jTextField3.getText();
    File fil = new File(fname);
    String password = "123456";

    SteganoInformation cls = new SteganoInformation(fil);

    VideoSteganography.retrieveFile(cls, password, true);

and the method is

public static boolean retrieveFile(SteganoInformation info, String password, boolean overwrite)
    {
        File dataFile= null;
        features= info.getFeatures();
        try
        {
            masterFile= info.getFile();
            byteArrayIn= new byte[(int) masterFile.length()];

            DataInputStream in= new DataInputStream(new FileInputStream(masterFile));
            in.read(byteArrayIn, 0, (int)masterFile.length());
            in.close();  
            messageSize= info.getDataLength();
            byte[] fileArray= new byte[messageSize];
            inputOutputMarker= info.getInputMarker();
            readBytes(fileArray);
.......
}

Notice the method readBytes above, it throws the exception and its written as below

private static void readBytes(byte[] bytes)
    {
        int size= bytes.length;

        for(int i=0; i<size ; i++)
        {


            bytes[i]= byteArrayIn[inputOutputMarker];
            inputOutputMarker++;



        }
    }

回答1:

The problem here is "byteArrayIn[inputOutputMarker]", Recheck the value of inputOutputMarker by and the range of values it could have .

回答2:

@Mazen Wadi , thanks for your reply. But i figured what triggered the very exception and would like to share in case some one would encounter the same problem. From the two classes "VideoSteganography class" and "SteganoInformation class" , there are two loops from the methods retrieveBytes() from both classes. Change loops to the one below and make sure the loop size tally in both classes. Note: change j=6 from retrieveBytes method of the two classes and your problem is solved.

private static void retrieveBytes(byte[] bytes)
        {
            int size= bytes.length;

            for(int i=0; i< size; i++)
            {
                byte1= 0;
                for(int j=6; j>=0; j-=2)
                {
                    byte2= byteArrayIn[inputOutputMarker];
                    inputOutputMarker++;

                    byte2&= 0x03;
                    byte2<<= j;
                    byte1|= byte2;
                }
                bytes[i]= byte1;
            }
        }

来源：https://stackoverflow.com/questions/15948815/video-steganography-in-java