Rate-Distortion Optimal Adaptive Quantization and Coefficient Thresholding for MPEG Coding
نویسندگان
چکیده
This paper presents an MPEG-2 compatible adaptive quantization algorithm that leads to the optimal encoding of I-frames in the sense of maximizing PSNR. It integrates three key features into a single Lagrangian optimization model: adaptive quantization including quantizer-change overhead consideration, coefficient thresholding, and a new coefficient amplitude reduction technique. Our results show that Iframes generated by the TM5 reference encoder are about 1.5-2.0 dB below the theoretical optimum.
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تاریخ انتشار 2002