Study of Dct Coeecient Distributions
نویسندگان
چکیده
Many image and video compression schemes perform the discrete cosine transform (DCT) to represent image data in frequency space. An analysis of a broad suite of images connrms previous nding that a Laplacian distribution can be used to model the luminance AC coeecients. This model is expanded and applied to color space (Cr/Cb) coeecients. In MPEG, the DCT is used to code interframe prediction error terms. The distribution of these coeecients is explored. Finally, the distribution model is applied to improve dynamic generation of quantization matrices.
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تاریخ انتشار 1996