Study of DCT coe cient 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 con rms previous nding that a Laplacian distribution can be used to model the luminance AC coe cients. This model is expanded and applied to color space (Cr/Cb) coe cients. In MPEG, the DCT is used to code interframe prediction error terms. The distribution of these coe cients is explored. Finally, the distribution model is applied to improve dynamic generation of quantization matrices.
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تاریخ انتشار 1996