## Ex. 3, Problem 1 - conv2 vs imfilter

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robert.n
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### Ex. 3, Problem 1 - conv2 vs imfilter

What is the difference between what conv2 does and what imfilter does?
For example conv2(image, filter, 'same') and imfilter(image, filter) with filter = [0.5 0 -0.5] seem to produce almost the same result (only the signs are inverted). However, conv2 is said to apply convolution and imfilter is said to apply a 2dimensional filter. What the f...?

And how are we supposed to calculate C? G is 25x25 and the other matrix is 2x2. How is the convolution operator used to "multiply" or combine these matrices (or are these matrices meant to be convolutions)?

In exercise 2 we combined 2 filters (= convolutions?) by multiplication of the related matrices. Though, the matrices must be properly sized to do this.

All in all... I'm confused.

// EDIT:
Conv2 vs. imfilter still is confusing, but I'm already finishing my solution for problem 1 anyway...