erode_black_edge v1.0

Expand edge pixel color of a premult image. It works to remove both bright and dark edges. It works based on traditional edge extend method of premult blur and unpremult. There is a view control added to see the bite point of expanding this view control will be helpfull to see the actual edge pixel which we are expanding

1. Expands pixel, 'erode more' control the blur command inside the tool 

2. This will judge actual Edge biting point, using this biting point the color pixel expands if we control this slide by setting the view alpha to Merge it will give us a clear idea of from which pixel its starts expanding THIS IS THE MAIN COMMAND IN THSI TOOL

3. It will reveal inner edge and protect the core area

4. Its kept to check the alpha 

5. Mask to limit the area to effect