Color filter arrays based on mutually exclusive blue noise patterns
Wei A. Zhu, Kevin J. Parker, Michael A. Kriss · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1998
The ordered color filter arrays (CFA) used in single sensor, color digital still cameras introduce distracting color artifacts. These artifacts are due to the phase shifted, aliased signals introduced by the sparse sampling by the CFAs. This work reports the results of an investigation on the possibility of using random patterns as a CFA for single sensor, digital still cameras. From a single blue noise mask pattern, three mutually exclusive, random CFAs are constructed representing the red, green, and blue color filters. An edge adaptive method consisting of missing-pixel edge detection and boundary sensitive interpolation is employed to reconstruct the entire image. Experiments have shown that the random CFA alleviates the problem of the low-frequency color banding associated with ordered arrays. This method also has the advantage of better preserving color free, sharp neutral edges, and results in less deviation from neutral on high frequency, monochrome information.