image to pencil sketch android

[GoogleCodeExporter]

Good day

I am doing an internship in Android. I am a novice right now. I have been 
allotted a project which requires converting an image into a pencil sketch.

I tried it using two methods
1. convert to grayscale
2. invert the image
3. GaussianBlur
4. colorDogde image 3 and image 1

and

1. SobelEdgeDetection
2. Invert the image

but both give a very hazy effect

Can anybody suggest me improvements on this?

Thanks

Original issue reported on code.google.com by dhwanich...@gmail.com on 4 Feb 2014 at 7:54

[GoogleCodeExporter]

Hello, try using Minimum filter with radius 2-3 instead of Gaussian Blur filter.

Original comment by madfo...@gmail.com on 27 Apr 2014 at 7:32

[Droidude]

I will recommend you reading the algrorithm https://github.com/geraintluff/canvas-sketch here.