Patent Document ID: 8666154
Application ID: 13345126
Patent Status: 1

Claim One:
1. A method of pixel interpolation in which a two-dimensional digital filter is arranged so as to interpolate an output pixel from a two-dimensional array of colour input pixels by aligning a filtering operation with a detected direction of an image feature at a pixel position to be interpolated; the method comprising: detecting image activity within respective colour components of a group of input pixels around the pixel position to be interpolated; generating monochromatic test pixels by combining the colour components of input pixels in relative proportions dependent upon the detected image activities; detecting the direction of an image feature in a group of the monochromatic test pixels around the pixel position to be interpolated; and interpolating an output pixel using the two-dimensional filter, according to the detected image feature direction; wherein the generating step comprises varying the relative proportions of the colour components in a monochromatic test pixel so that colour components with higher image activity contribute a generally higher proportion of the monochromatic test pixel.