text: /**
   * Adjusts the brightness of the image by going over to HSV values.
   * Negative values decrease brightness while positive values increase brightness.
   */
  function BrightnessFilter(){
  	this.name = "Brightness";
  	this.defaultValues = {
  		amount : 0.0
  	};
  	this.valueRanges = {
  		amount : {min:-1.0, max:1.0}
  	};
  	if(!FilterUtils){
  		if(console){
  			console.error("Unable to find filterutils.js, please include this file! (Required by " + this.name + " filter)");
  		}
  		return;
  	}
  	var filterUtils = new FilterUtils();
  	this.filter = function(input,values){
  		var width = input.width, height = input.height;
  	  	var inputData = input.data;
  	  	if(values === undefined){ values = this.defaultValues; }
  	  	var amount = (values.amount === undefined) ? this.defaultValues.amount : values.amount;
  	  	for (var y = 0; y < height; y++) {
  	        for (var x = 0; x < width; x++) {
  	            var pixel = (y*width + x)*4;
  	            var hsv = filterUtils.RGBtoHSV(inputData[pixel],inputData[pixel+1],inputData[pixel+2]);
  	            hsv[2] += amount;
  				if(hsv[2] < 0){
  					hsv[2] = 0;
  				} else if (hsv[2] > 1){ 
  					hsv[2] = 1;
  				}
  				var rgb = filterUtils.HSVtoRGB(hsv[0],hsv[1],hsv[2]);
  				for(var i = 0; i < 3; i++){
  					inputData[pixel+i] = rgb[i];
  				}
  	        }   
  	    }
  	}			
  }
  