How to coloured outline the region I want?

I want to highlight/coloured the outline vein at my hand image and I tried many codes but it doesn't work.

Answer 1

[Image Analyst]

See here for algorithms:

http://www.visionbib.com/bibliography/people943v1.html

[Atifah Samuri]

thank you

Answer 2

[yanqi liu]

yes，sir，may be use some image enhancement to adjust the image

[Atifah Samuri]

Thank you. what value is this in the code? If I use this code for another image, I did'nt get the highlighted one. Why?

[Atifah Samuri]

Why you delete the code? I want to ask what is the "t" value in the code.

[yanqi liu]

sorry，sir，the code just develop base on the upload image，and the t is just an roi to make hand mask，avoid the background noise

[Atifah Samuri]

do you have any code that i can use for different images?