Image color correction in DCT domain

A commonly used method of color correction for digital cameras utilizes a 3×3 correction matrix with the coefficients optimized to achieve maximum color fidelity. Although this operation leads to significant improvement in color rendering, it amplifies noise at the same time. This paper presents a new method of performing color correction in DCT domain that reduces noise amplification. The paper shows that the color correction operation performed in DCT domain is more computationally efficient than the same operation that is traditionally performed in the image domain. It is also shown that gamma correction can be applied before color correction because the introduced color distortions measured in the perceptually uniform CIE Luv color space are below the human sensitivity threshold and do not affect perceptual quality of processed images. As a result, the proposed solution leads to revision of the commonly used color processing/compression chain of digital cameras reducing its computational complexity and improving image quality.

[1]  Kyu-Ik Sohng,et al.  Optimal Piece Linear Segments of Gamma Correction for CMOS Image Sensors , 2005, IEICE Trans. Electron..

[2]  Wanqing Li,et al.  Novel color processing architecture for digital cameras with CMOS image sensors , 2005, IEEE Transactions on Consumer Electronics.

[3]  Alessandro Rizzi,et al.  Perceptual Color Correction Through Variational Techniques , 2007, IEEE Transactions on Image Processing.

[4]  Moon Gi Kang,et al.  Design of real-time image enhancement preprocessor for CMOS image sensor , 2000, IEEE Trans. Consumer Electron..

[5]  Amine Bermak,et al.  An analog gamma correction method for high dynamic range applications , 2011, 2011 IEEE International SOC Conference.

[6]  R. J. Green,et al.  Colour error reduction in video systems , 1990 .

[7]  Cormac Herley,et al.  Trade-offs between color saturation and noise sensitivity in image sensors , 1998, Proceedings 1998 International Conference on Image Processing. ICIP98 (Cat. No.98CB36269).

[8]  Rastislav Lukac Perceptual Digital Imaging : Methods and Applications , 2012 .

[9]  Gunhee Han,et al.  CMOS image sensor with analog gamma correction using nonlinear single-slope ADC , 2006, 2006 IEEE International Symposium on Circuits and Systems.

[10]  Igor Kharitonenko,et al.  Suppression of noise amplification during colour correction , 2002, IEEE Trans. Consumer Electron..