Image analysis – Image compression or coding – Quantization
Reexamination Certificate
2007-10-23
2007-10-23
Couso, Jose L. (Department: 2624)
Image analysis
Image compression or coding
Quantization
Reexamination Certificate
active
10473029
ABSTRACT:
A rounding accuracy of DCT coefficients that are quantized is dynamically varied with a simple structure. As a result, an encoding noise is effectively suppressed and the picture quality is prevented from being deteriorated. DCT coefficients of which a picture signal is transformed by DCT are input to a quantizing circuit30. The quantizing circuit30quantizes the DCT coefficients with a quantizer matrix and supplies the quantized DCT coefficients to a multiplying device33through an absolute value circuit31. A quantizer scale value based on the generated code amount of the entire screen is converted into an invert value thereof and then supplied to a multiplying device33. In addition, an M value designating circuit38designates a value M as a parameter with which a rounding accuracy of DCT coefficients that are quantized is controlled according to a quantizer scale value. An adding device34adds the value M to an output of the multiplying device33. A five-bit shifting circuit35rounds off a decimal part. At that point, as the quantizer scale value becomes large, the rounding accuracy of DCT coefficients that are quantized is designated so that the round off direction becomes large. Thus, the DCT coefficients are quantized so that the amplitude is not increased. As a result, the encoding noise can be suppressed.
REFERENCES:
patent: 5754699 (1998-05-01), Sugahara
patent: 6208692 (2001-03-01), Song et al.
patent: 6434196 (2002-08-01), Sethuraman et al.
patent: 6560371 (2003-05-01), Song et al.
patent: 6-22292 (1994-01-01), None
patent: 10-304362 (1998-11-01), None
Kitamura Takuya
Sugiyama Akira
Togashi Haruo
Couso Jose L.
Frommer William S.
Frommer & Lawrence & Haug LLP
Levy Paul A.
Sony Corporation
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