Hi, I had a similar issue. After trying different things, I found out that the color space you are using (CGColorSpaceCreateDeviceGray()) produces this kind of result. However, after trying this with CGColorSpace(name: CGColorSpace.linearGray), the result are much more accurate.

Is the sample code working as expected? Have you been able to process a captured area? I tried running the sample code on my iPad Pro (11-inch) (4th generation), when capturing an area, and pressing the "Next" Button, an overlay with a white dot in the center appears. Everything else is blurred out. I am also facing other issues regarding the UI of the sample app.