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by KRAKRISMOTT 1082 days ago
Isn't matrix multiplication already a convolution? You are rotating the right hand side matrix anti clockwise 90 degrees and then convolving it upon the LHS matrix from top to bottom.
2 comments

The point above regarding convolution had to do specifically with accelerating 3x3 and above convolutional operations, as the product and the accumulation can be done in a few clock cycles if setup with care and love.
no, it is not, and i am not

discrete convolution is cₙ = Σᵢaᵢbₙ

there is no way in which the indexes into the input matrices in a matrix multiplication are formed from sums or differences of indices and dummy variables

however, convolution is a matrix multiplication, specifically multiplication by the circulant matrix of the convolution kernel

hth, hand

Sure it doesn't sum the whole matrix but it does sum row by row. Also how did you type out LaTeX in HN? Or is that a font?
it sums products, but convolution is summing products in a particular way that is not general matrix multipication

i typed special characters with the compose key; cf. https://github.com/kragen/xcompose

not as easy as latex but more compatible