In this paper, a design technique of JPEG quantization table is proposed for photos with face whose size is 128 * 128 in wireless handset. The small size images may have different characteristics from the large images used in PC. Also, the photos with face have their own characteristics. From these two facts, new quantization table design is proposed in this paper. The quantization tables are derived from R-D optimization for the photos with face and it is shown that the proposed quantization tables have good performances for size and quality. In R-D optimization, the obtained quantization table is image-specific and cannot be applied to other images. In the proposed method, the quantization tables are obtained from various photo samples and final table is gotten as average of them. This makes the final quantization tables applied to other photos with face. Also, it is possible to control the quality factor based on the interpolation of high quality quantization table and middle quality quantization table. Simulation results show that the obtained quantization table makes the compressed file size small and the image quality improved in general cases.
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