A set of even interpolated sub-pixels is formed based on a pixel window and a tap coefficient register having a tap coefficient set, the pixel window is shifted and, applying the tap coefficient register a set of odd interpolated pixels is formed. The set of even interpolated sub-pixels and the set of odd interpolated sub-pixels are accumulated, repeatedly, until a termination condition is let. In the accumulating, the tap coefficient register is updated with another tap coefficient set, the pixel window is shifted, and the even interpolated pixels are incremented, the pixel window is then shifted again and the odd interpolated pixels are incremented.