Co-occurrence matrix

A co-occurrence matrix or co-occurrence distribution is a matrix that is defined over an image to be the distribution of co-occurring pixel values (grayscale values, or colors) at a given offset.

For an image with ${\displaystyle p}$ different pixel values, the ${\displaystyle p\times p}$ co-occurrence matrix C is defined over an ${\displaystyle n\times m}$ image I, parameterized by an offset ${\displaystyle (\Delta x,\Delta y)}$, as:

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