Digital Image Processing (using Java)

int numPixels = n*n;short[] image = new short[numPixels];randomFill(image);// Perform the mapping directlyIntervalTimer timer = new IntervalTimer();timer.start();for (int i = 0; i < numPixels; ++i)image[i] = (short) Math.round(Math.sqrt(image[i]));System.out.println("direct calculation: " + timer.stop() + " sec");// Perform the mapping with a lookup tablerandomFill(image);timer.start();short[] table = new short[256];for (int i = 0; i < 256; ++i)table[i] = (short) Math.round(Math.sqrt(i));for (int i = 0; i < numPixels; ++i)image[i] = table[image[i]];System.out.println("lookup table: " + timer.stop() + " sec");}System.exit(0);}• Java MapTest1- 21 -