How can I colour my sketch using pen tool within the limited edge boundaries using sobel edge detection/canny edge detection in ios swift?

Question

I am using GPUImage to detect the edge and applying GPUImageSobelEdgeDetectionFilter or GPUImageCannyEdgeDetectionFilter . Now my requirement is:

How ca

Answer 1

Hey Pradip you are looking for floodfill algorithm to be exact it will solve your problem.

Floodfill Algorithm Brief Explanation -

The flood-fill algorithm takes three parameters: a start node, a target color, and a replacement color. The algorithm looks for all nodes in the array that are connected to the start node by a path of the target color and changes them to the replacement color.

Links for you R&D and also a demo in obejective-c.

1. https://ilearnios.wordpress.com/2013/07/18/scanline-flood-fill-algorithm-with-or-without-tolerance-in-objective-c/
2. https://lodev.org/cgtutor/floodfill.html

3. https://github.com/Chintan-Dave/UIImageScanlineFloodfill (Great demo courtesy of Chintan-Dave)

   I have also used floodfill on my project just to remove background colors and found above links veryusefull. Hope it Helps