Back to results
US 8,014,617 B2Granted
Decoding apparatus, dequantizing method, distribution determining method, and program thereof
AssigneeFuji Xerox Co., Ltd.
InventorShunichi Kimura
Life of this patent
Estimating the term…
Abstract
A decoding apparatus includes a random number generating section and a decoding section. The random number generating section generates random numbers according to distribution of original data corresponding to respective quantization indexes. The decoding section generates decoded data on a basis of the random numbers generated by the random number generating section.
Claims3
A decoding apparatus comprising:
- a distribution estimating section that estimates distribution of original data corresponding to quantization indexes executed by a controller, comprising:
- a frequency distribution measuring section that measures a frequency distribution based on the quantization indexes and acquires a maximum value of absolute values of the quantization indexes qM;
- a histogram normalizing section that normalizes the frequency distribution measured by the frequency distribution measuring section and generates a normalized histogram;
- a preset value acquiring section that determines the preset value based on the maximum value of absolute values of the quantization indexes acquired by the frequency distribution measuring section;
- and
- a standard-deviation estimating section that calculates a standard deviation using an equation:
- σ
- =
- -
- (
- 2
-
- N
- +
- 1
- )
-
- D
- 2
-
- log
-
- [
- 1
- -
- ∑
- q
- =
- -
- N
- N
-
- H
-
- (
- q
- )
- ]
- ,
- wherein σ is the standard deviation, N is the preset value, H(q) is the normalized histogram, q is the quantization indexes and D is a quantization step size.
37 more elements
Dependencies are inferred from the claim text.