red Pixel values in ditinct points

I have a separate part of the picture. Had placed the image into a new coordinates. How can I get the red Pixel values in the points of x-y coordinate?

Answer 1

[Image Analyst]

See my color segmentation demos in my File Exchange. They do that (find red pixels), though I'm not exactly sure what you mean by "points of x-y coordinate".

http://www.mathworks.com/matlabcentral/fileexchange/?term=authorid%3A31862

[fereshte]

My x-axis from 0 to 128 that I want to each point of x get the average of all red pixels valuse Along the x

[Image Analyst]

OK, you can do that, just segment it to get a binary image, redMask, and then use find and mean:

[rows, columns] = find(redMask);
meanX = mean(columns);

[fereshte]

thanks i want to get mean of green pixel values along the point such x=20 in RGB image.can you help me?

[Image Analyst]

Try this:

greenLine20 = rgbImage(20,:,2); % Extract line 20 of the green channel.
meanGreenLine20 = mean(greenLine20); % Get its mean.

[fereshte]

what is 2 in this code?(rgbImage(20,:,2)). response is zero!!why?

[Image Analyst]

The 2 means color channel 2, which is green. Here, run this code:

rgbImage = imread('peppers.png');
greenLine20 = rgbImage(20,:,2); % Extract line 20 of the green channel.
meanGreenLine20 = mean(greenLine20); % Get its mean.

Do you get a 512 element long array for greenLine20? And a value of 36.3770 for the mean? If you don't get that for your image, then attach it.

[fereshte]

no image size is 47*108. thank you i use other function for this problem.

[Image Analyst]

Okay, whatever...as long as you got it working.