My edit to the original project: Floodfill now works also at the inner 1px at borders of the image.
Magic wand tool (fuzzy selection) by color for Javascript
Live example: http://jsfiddle.net/Tamersoul/dr7Dw/
Magic Wand Control for Openlayers 2.13 (use only for "google" and "grid" layers with CORS support)
Live Openlayers example: http://jsfiddle.net/Tamersoul/uBL5C/
Enjoy.