Patent ID: 8731323

Claim:
An apparatus for removing banding artifacts, comprising: a block classification processing module; and a de-banding filtering module coupled to the block classification processing module, wherein the block classification processing module comprises: an edge detection unit; and a block classification unit coupled to the edge detection unit, wherein the block classification unit is configured to differentiate flat blocks and texture blocks, wherein the de-banding filtering unit is configured to removing banding artifacts according to the equation { I ′ ⁡ ( x , y ) = I 0 + FiltThresh , if ⁢ ⁢ I ⁡ ( x , y ) > ( I 0 + FiltThresh ) ; I ′ ⁡ ( x , y ) = I 0 - FiltThresh , if ⁢ ⁢ I ⁡ ( x , y ) < ( I 0 - FiltThresh ) ; I ′ ⁡ ( x , y ) = I ⁡ ( x , y ) , else . ⁢ ⁢ I ″ ⁡ ( x , y ) = ∑ x = 0 ( WinH - 1 ) ⁢ ⁢ ∑ y = 0 ( WinW - 1 ) ⁢ ⁢ I ′ ⁡ ( x , y ) WinH × WinW , ⁢ and wherein FiltThresh comprises a definable sigma in the equation that is controllable to steer the filter strength, I 0 comprises a gray value of the current pixel under processing which is located in the center of filter window, a current window size WinSize is WinW×WinH, FiltThresh further comprises the manually selected threshold for de-banding filtering, I(x,y) comprises a pray value of each pixel located within the filter window, I′(x,y) comprises an intermediate filtered output, and I″(x,y) comprises a final filtering output.