Abstract
A correlative directional interpolation that realizes improvements of luminance signal resolution and pseudo-color reduction is proposed for progressive scan CCD (PS-CCD) with Bayer color filter array, which consists of checkered G filters and line-alternated R and B filters. First, a correlative direction on a target pixel is detected by calculating horizontal and vertical correlations between a target pixel and its adjacent pixels. Next, according to the correlative directions, two primary color signals that are not the target pixel' s color signal are interpolated as follows. The one on the correlative directional line is interpolated using fact that the color-difference signal for the target pixel is almost the same as averaged color-difference signal on the target line in the correlative direction. The other one not on the correlative directional line is interpolated using fact that the color-difference signal gradually changes toward any direction, even a direction with no correlation. Performance of this methodology is verified by software simulation. Result of software simulation indicates that this method has better transient characteristics and less pseudo-color than conventional method. These superior efficiencies have been performing this method a mainstream of signal processing for color video camera with a Bayer-filtered PS-CCD.
