function ImagePreloader(images, callback) {
        // store the call-back
        this.callback = callback;

        // initialize internal state.
        this.nLoaded = 0;
        this.nProcessed = 0;
        this.aImages = new Array;

        // record the number of images.
        this.nImages = images.length;

        // for each image, call preload()
        for ( var i = 0; i < images.length; i++ ) {
            this.preload(images[i]);
        }
    }

    ImagePreloader.prototype.preload = function(image) {
       // create new Image object and add to array
       var oImage = new Image;
       this.aImages.push(oImage);

       // set up event handlers for the Image object
       oImage.onload = ImagePreloader.prototype.onload;
       oImage.onerror = ImagePreloader.prototype.onerror;
       oImage.onabort = ImagePreloader.prototype.onabort;

       // assign pointer back to this.
       oImage.oImagePreloader = this;
       oImage.bLoaded = false;

       // assign the .src property of the Image object
       oImage.src = image;
    }

    ImagePreloader.prototype.onComplete = function() {
       this.nProcessed++;
       if ( this.nProcessed == this.nImages )
       {
          this.callback(this.aImages, this.nLoaded);
       }
    }

    ImagePreloader.prototype.onload = function() {
       this.bLoaded = true;
       this.oImagePreloader.nLoaded++;
       this.oImagePreloader.onComplete();
    }

    ImagePreloader.prototype.onerror = function() {
       this.bError = true;
       this.oImagePreloader.onComplete();
    }

    ImagePreloader.prototype.onabort = function() {
       this.bAbort = true;
       this.oImagePreloader.onComplete();
    }