Get Pixel Values from Image

I’m trying to create a special terrain with its own algorithm from a heightmap. So that I can do with it has to read individual pixels in an image (heightmap). Unreal now converts imported images to Texture2D. In this class, I do not find the desired data.

Could someone tell me how I could solve the problem?
Would it help if I choice the values ​​externally? But how would I then import this list of values ​​in Unreal?


I wrote a small guide on how to do this here: