Help me to detect the fathom (deep place) from an image using matlab codes?

I need a help to detect fathom area(deep geographical area) in an image and if majority of the image is of deep place, it should be also noted.

[Walter Roberson]

http://www.mathworks.com/matlabcentral/answers/7924-where-can-i-upload-images-and-files-for-use-on-matlab-answers

Answer 1

[Image Analyst]

I assume you have an image that is a topographical map. So in that case you can either use thresholding to detect deep areas on an absolute depth basis, or use imregionalmin() to find local mins in the depths. More info (such as an image) will get you better answers.