Reversing Demosaicking and Compression in Color Filter Array Images

An alternative processing chain of digital still camera (DSC) has been proposed by moving the compression process before demosaicking to avoid additional data redundancy introduced by the demosaicking process. Recent empirical studies have shown that the alternative processing chain can actually outperform the conventional one in terms of image quality at low compression ratios. To provide theoretically sound basis for such conclusion, we propose analytical models for the reconstruction errors of the two processing chains. The models developed confirm the results of existing empirical studies and also allows performance predictions for more advanced compression and demosaicking methods, thus providing important cues for development in this area.