In one embodiment, the method includes determining a reference pixel group including a pixel to be filtered. The reference pixel group includes at least three successive pixels. Two of the three successive pixels are in a first block and one of the three successive pixels is in a second block. The second block is adjacent to the first block. The method further includes applying weight factors to at least each of the three successive reference pixels. The weight factors are different according to pixel position. A filtered value is obtained by summing at least the three weighted successive pixels.