I'm new to image processing, but I have good knowledge of general data processing.
Could you please suggest an approach which can be used to segment images like this? I suppose it is some kind of local basin and the segment should stop a larger gradients. However, some outside region may also become dark as seen in the top right corner.
Here the result should be the two dark blobs. Ideally I'd like to use existing packages in Python.
UPDATE: Here is another example showing the more difficult parts: The ideal result would be only those two elliptical blobs. Not all blobs are perfectly elliptical though as seen in the first image. You also see that there is a surrounding which in the end should not confuse the algorithm. Especially the small circle in the last image seems pretty tough to get.