Crop image

Hi,

This is NICK.I want to selct a pixel os size 100*100 or 50*50.

I have to do A) Define Mask size (Y*Y) square input in the code I used. B) Move the Mask systematically around image(either in upward or side ward direction). c) Within each area,identify Blank area(white zone)-Brown Infill material (white in picture)-green identify shallow pores -yellow Rock-Blue

http://i39.tinypic.com/wtho5j.jpg. Please give me one example or sample code to solve it.

Thank you, NICK

Answer 1

[Image Analyst]

Check out the help for rbbox, and imcrop. Then check out my BlobsDemo:

http://www.mathworks.com/matlabcentral/fileexchange/25157-blobsdemo

Check out my other submissions to do color segmentation.

By the way, I'm not sure what step B is or why you think it is necessary. You can find the white blobs simply by thresholding the image - you don't need to scan any mask around.

[Nick ALan]

@Image Analyst I want step B to extend it so that I can easily identify pores (shallow pores).Will you give me code for the solution.........

[Image Analyst]

Like I said I see no reason at all for systematically moving a window around when you can get everything all in one shot, in one single line of code. Doing your Step B won't help one bit.

Answer 2

[Image Analyst]

See Steve's demo:

http://blogs.mathworks.com/steve/2006/06/02/cell-segmentation/

[Nick ALan]

@ Image Analyst Today I am full busy with other work.I will look at it in the evening and will message you if any help is required.

Answer 3

[Walter Roberson]

Your image does not have sufficient resolution to be able to detect the pores in the basalt sample.

In a series of earlier threads since deleted by the poster (aggh!) I posted specific references to studies of pore size ranges in basalt. I then demonstrated that optical wavelengths were too long by a minimum factor of 200 to be able to detect the basalt pore positions even at only 1 pixel per pore.

[Nick ALan]

@ Walter Roberson I had searched about basalt cubes in the answers section but I didn't find anything. The threads were deleted why????whether I can found any image of the previous thread.My task is to select any basalt image and select a pixel of 100*100 or 50*50 and extend it in upward or sideward direction.Will you give me an example and code for it to solve.

Your help is highly required.

[Walter Roberson]

I never got a clear answer as to why that poster kept deleting the older questions as they went along, even though we requested that they not do that.

I already told you to use ginput() or rbbox() to get the input point. Get the coordinate of the lower-left corner. Add 10 to both the x and y in order to get the upper right coordinate. Extract the block between and do whatever you want with it.

I am quite busy these days, and will not be able to assist further in this matter.