Digital negative image with Actionscript 3.0

[Flep]

You need to apply a digital negative effect on one or more images?
This article will show you how to do it using a digital negative matrix applied to the image with the ColorMatrixFilter class.
Applying to it an interval, we could play with it quite a lot...
In this example I apply 3 sliders to check the red, green and blue channels of the digital negative matrix.

Let's look at the example:

I create a FLA and save it as 'negativo.fla' in which,
I create 2 instances MovieClip named respectively 'img_mc' and 'pic_mc' inside which I insert an image.
I create 3 instances of the Slider component named respectively 'red_slider', 'green_slider', 'blue_slider'.
I create a Document Class, an AS file saved as 'Negativo.as', implemented the following way:

package
{
	import flash.display.MovieClip;
	import flash.filters.ColorMatrixFilter;
	import flash.events.Event;
	
	public class Negativo extends MovieClip
	{
		public function Negativo()
		{
			init();
			listener();
		}
		
		private function init():void
		{
			stage.frameRate=31;
			
			pic_mc.filters=[new ColorMatrixFilter(
			[-1,0,0,0,255,
			0,-1,0,0,255,
			0,0,-1,0,255,
			0,0,0,1,0])];
			
			red_slider.minimum=0;
			red_slider.maximum=255;
			red_slider.value=255;
			green_slider.minimum=0;
			green_slider.maximum=255;
			green_slider.value=255;
			blue_slider.minimum=0;
			blue_slider.maximum=255;
			blue_slider.value=255;
		}
		
		private function listener():void
		{
			pic_mc.addEventListener(Event.ENTER_FRAME,go);
			function go(e:Event):void
			{
				e.target.filters=[new ColorMatrixFilter(
				[-1,0,0,0,red_slider.value,
				0,-1,0,0,green_slider.value,
				0,0,-1,0,blue_slider.value,
				0,0,0,1,0])];
			}
		}
	}
}

The result:

Let's analise the code.

Methods

init();
I impost the frame rate
stage.frameRate=31;
I apply the negative matrix to 'pic_mc' using a new instance of the ColormatrixFilter class and assigning to it the filters property of the MovieClip (in fact 'pic_mc')
pic_mc.filters=[new ColorMatrixFilter(
[-1,0,0,0,255,
0,-1,0,0,255,
0,0,-1,0,255,
0,0,0,1,0])];
for each slider I assign a minimum and maximum value (minimum zero, maximum 255...the maximum value of the RGB scale) and also a starting value
red_slider.minimum=0;
red_slider.maximum=255;
red_slider.value=255;
green_slider.minimum=0;
green_slider.maximum=255;
green_slider.value=255;
blue_slider.minimum=0;
blue_slider.maximum=255;
blue_slider.value=255;

listener();
I add an interval ENTER_FRAME
pic_mc.addEventListener(Event.ENTER_FRAME,go);

go(e:Event):void
I apply the negative matrix based on the values obtained from the positions of the three sliders
e.target.filters=[new ColorMatrixFilter(
[-1,0,0,0,red_slider.value,
0,-1,0,0,green_slider.value,
0,0,-1,0,blue_slider.value,
0,0,0,1,0])];

Stay tuned !