A Novel Method of Lossy Image Compression for Digital Image Sensors with Bayer Color Filter Arrays

Abstract

Through an analysis of existing compression-first methods, this paper presents a novel method of lossy image compression for digital color image sensors with Bayer color filter arrays (CFAs). In this method, an optimized compression and decompression structure is presented, and the captured CFA raw data is firstly low-pass filtered in RGB space by a smoothing filter followed by the down-sampling operation. Then, the data are transformed from RGB space to YCbCr space. Lastly, the filtered data in YCbCr are compressed directly before full color interpolation that introduces redundancy. The presented method can provide lower compression ratio (bit/pixel) and lower complexity than conventional interpolation-first image compression methods and other existing similar compression-first methods.