Image subtraction for vessel segmentation in angiogram image?

I have an angiogram image with varying background over which I need to perform vessel segmentation. performing the segmentation without image subtraction is not giving me a clean segmented image(there are traces of the background). I think it is because of the variation in my background. How do I create a uniform background? I do have background images, but just subtraction does not work very well, since the vessel's are also dark. Anyone know what to do?

[sammer zai yousuf zai]

i am also searching for the same answer..abhijit if you come to know the answer please share it

Answer 1

[Nitin]

you could try enhancing the image , it all depends on the type of noise present in the image, for example histeq or finding the edges using canny or sobel edge detection to get an approximate location of the region of interest and eliminating the rest ..