The Convolution Kernel effect changes the brightness values of each pixel in the clip according to a mathematical operation known as a convolution. The Convolution Kernel Settings include a set of controls that represent cells in a 3x3 grid of pixel brightness multipliers. Labels on the controls, which begin with the letter “M,” indicate their position in the matrix. The M11 control, for example, affects the cell in the first row and first column of the grid; the M32 control affects the cell in the third row and second column. The pixel being evaluated falls in the center of the grid, at the M22 location. Use this effect for fine control over the parameters of various emboss, blur, and sharpen effects. For a given effect, it is easier to apply one of the Convolution Kernel presets and to modify it, than to create the effect from scratch using the Convolution Kernel effect itself.

Convolution Kernel pixel grid, showing the position of each control in the matrix