Implementation of automatic white-balance based on adaptive-luminance

Abstract

A novel automatic white-balance algorithm based on adaptive-luminance is proposed in this paper. This algorithm redefines the gray pixels region, which can filter the gray pixels accurately. Furthermore, with the relations between gray pixels’ luminance with standard light source and their chroma Cb, Cr shifts with other color temperatures, the algorithm establishes the equations between the captured pixels and the original ones, which can estimate the gains of RGB channels exactly. To evaluate the proposed algorithm, the objective comparison method and the subjective observation method are both used, and the test results prove that the effects of image emendated by the proposed algorithm are excelled to that by traditional algorithms. Finally, the algorithm is implemented with VLSI design, and the result of synthesis proves that it can satisfy real-time application.

Keywords

Color Temperature / White Balance / VLSI Design / Gray Pixel / YCbCr Color Space

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