code: private ImageProcessor brightness(ImageProcessor ip, String brightAmt) {
          if (brightAmt != null) {
              try {
                  float bright = Float.parseFloat(brightAmt);
  
                  if (bright < 0) {
                      return ip;
                  }
  
                  ip.multiply(bright);
  
              }
  
              // no need to do anything with number format exception since the servlet
              // returns only images; just return the original image
              catch (NumberFormatException e) {
              }
          }
  
          return ip;
      }
docs: Adjusts the brightness of an image by a supplied amount.
  
  @param ip
  The image to adjust the brightness of brightAmt The amount to
  adjust the brightness of the image by 0 <= brightAmt < 1 : darkens
  image 1 = brightAmt : original image 1 < brightAmt : brightens
  image
  @return The image with brightness levels adjusted