Approaches

From what I've read online, we have a few choices to isolate the brain:

• Thresholding
• Canny Edge Detection + Morphological "Fill in"
• Sobel Filter + Markers + Watershed Transform

There seem to be many choices of filters that will pick out edges. Both Sobel and Canny use a convolution kernel which essentially calculates derivatives of gray scale values in the 8 cardinal directions.

Preprocessing we might want to think about:

• Denoising
• Smoothing with a Gaussian or "Disk Median"