Crop an image with special frame

Question

I am writing an application for android. I need to implement something like below image(From LG's wallpaper selection tool). The original image does not have a circle.

The actual image is cropped to outside rectangle, but thumbnail images are cropped to the inside circle.

I want to implement something like this, but the guide is not a rectangle, but a circle. Is there any examples or library for this?

Answer 1

I wanted to implement the same thing, so I modified edmodo cropper to have circular selection. Take a look at my library CircleImageCropper.