How to measure an orientation of a line for every 10 pixels

I am having difficulties in measuring the orientation of each line (per 5 or 10 pixels) in the image attached. I have tried to run the regionprops function and call for orientation, but I just cannot get it right. Else, I also don't have any idea how to separate the measurement for each line in the middle area, since it has more than one line in x direction. I really appreciate if someone can teach me how to do it here. Cheers