How to Load 3D Array faster from a DataInputstream

Question

Hi,
I have a task like reading a file using fileinputstream and loading the values into a 3Dimensional array. Before loading the array I need to convert each byte that i read into LittleEndian. I am attaching the code here
     public boolean loadIter(int iter) {
          try {
               picArray = new float[NUMOFIMAGES][HEIGHT][WIDTH];
               word = new byte[8];
               file = new File(fileName);
/*            long start = System.currentTimeMillis( );
*/               fileInput = new FileInputStream(file);
               dataInputStream = new DataInputStream(fileInput);
               dataInputStream.skipBytes(iter*NUMOFIMAGES*HEIGHT*WIDTH*4);
                    maxAll = 0;
                    for (int l = 0; l < NUMOFIMAGES; l++) {
                         for (int k = 0; k < HEIGHT; k++) {
                              for (int j = 0; j < WIDTH; j++) {
                                   dataInputStream.readFully(word, 0, 4);
                                   float in = Float.intBitsToFloat((word[3]) << 24 | (word[2] & 0xff) << 16
                                         | (word[1] & 0xff) << 8 | (word[0] & 0xff));
                                   picArray[l][k][j] = in;
                                   if(in > maxAll)
                                        maxAll = in;                                   
               fileInput.close();
/*            System.out.println(" Elapsed time is "+(System.currentTimeMillis()-start)/ 1000F
                        + "Seconds.");
*/               return true;
          } catch (IOException ioe) {
               System.err.println("initFile ioe " + ioe.getMessage());
               return false;
     }The above process is taking abt 15sec for 126(NUMOFIMAGES) 212(HEIGHT) & 212(WIDTH) which are constants for me. How can I make this whole thing faster. Are there any other techniques to improve performance?
Thanks

Answer 1

Create your DataInputStream like this:
dataInputStream = new DataInputStream(new BufferedInputStream(fileInput));
Does that help?