Low-complexity film grain simulation technique

Abstract From the Canadian patent

The simulation of film grain in a video image occurs by first creating a block (i.e. a matrix array) of transformed coefficients for a set of cut frequencies fHL, fVL, fHH and fVH associated with a desired grain pattern. (The cut frequencies fHL, fVL, fHH and fVH represent cut-off frequencies in , two dimensions, of a filter that characterizes the desired film grain pattern). The block of transformed coefficients undergoes an inverse transform to yield a bit-accurate film grain sample and the bit accurate sample undergoes scaling to enable blending with a video signal to simulate film grain in the signal.