[M, N, ~] = size(im) why we use

[M, N, ~] = size(im) why we use

Answer 1

[Image Analyst]

They just want to know the number of rows and columns and don't care how many higher dimensions there are.

For images that may possibly be gray scale or color, I do this:

[rows, columns, numberOfColorChannels] = size(yourImage)

Note how I used more descriptive variable names that your code did. For grayscale, numberOfColorChannels = 1. For RGB, numberOfColorChannels = 3.

For a thorough explanation see Steve's blog: https://blogs.mathworks.com/steve/2011/03/22/too-much-information-about-the-size-function/

Answer 2

[Walter Roberson]

Read the documentation about size() again, paying attention to the definition of the output when you the number of output is less than the number of dimensions of the data.

[zakir khan]

~ asking about this sign for

example n is number of row and m is show number of column what dose this sing [M, N, ~] mean here

[Walter Roberson]

https://www.mathworks.com/help/matlab/matlab_prog/ignore-function-outputs.html

See also https://www.mathworks.com/help/matlab/matlab_prog/ignore-function-inputs.html