View pixel intensities of an image

Question

How to view the pixel intensities of an image in matlab by moving the mouse pointer over the image?

I used:

imshow(imread('image.jpg'));

But there is no option to view the pixel intensities of each pixel in the image.

For example,

      In MS-paint, while moving the mouse pointer 
      over the image we can see the location of 
      the pixel such as (20, 117) at the status bar.

But I need to see the pixel intensity instead.

Is there any other option to view it. Or I need to code to view it?

Related: http://stackoverflow.com/questions/687261/converting-rgb-to-grayscale-intensity — Rody Oldenhuis, Jul 10 '13 at 05:53

user2522560 · Answer 1 · 2013-07-10T06:43:18.857

2

One other option which is more interactive is

   imtool(imread('image.jpg')); % For GrayScale Image

   imtool(rgb2gray(imread('image.jpg')));  % For RGB Image

edited Jul 10 '13 at 06:43

answered Jul 10 '13 at 06:31

user2522560

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score 1 · Answer 2 · answered Jul 10 '13 at 05:55

1

If you want to create an intensity map, you can use MATLAB's rgb2gray. This will convert the n-by-m-by-3 RGB array you got from imread to an n-by-m matrix which contains the pixel intensities.

You can then point the interactive data cursor to this intensity matrix for the current mouse coordinates.

answered Jul 10 '13 at 05:55

Rody Oldenhuis

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Thank you. Its working. I just typed two lines imshow(imread('image.jpg'));datacursormode on; Now By moving the cursor on the image the intensities are displayed along with the X,Y,Z coordinates. – user2522560 Jul 10 '13 at 06:04
@user2522560: oh wow, even simpler; did not know that :) Well, good for you! Remember that you can mark this answer as accepted by clicking the big "tick" mark next to it. – Rody Oldenhuis Jul 10 '13 at 06:08
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For gray scale image it works, For RGB image we need to convert the image to rgb using rgb2gray and then proceed further like this imshow(rgb2gray(imread('image.jpg'))); datacursormode on; You are right. Thank you. – user2522560 Jul 10 '13 at 06:25

score 0 · Accepted Answer · answered Jul 10 '13 at 06:07

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you have impixelinfo and impixelinfoval for showing interactive information.

answered Jul 10 '13 at 06:07

Shai

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View pixel intensities of an image

3 Answers3