US5444487A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Adaptive dynamic range encoding method and apparatus
Assignee: Sony Corp
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Filing: 1993-12-07
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Granted: 1995-08-22
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Expires: 2013-12-07
Abstract
Abstract An adaptive dynamic range encoding method and device in which evaluation data mainly centered about the amount of the change in the spatial direction of picture data in a block is detected, and re-quantization is performed which will give a minimum value of the evaluation data. The re-quantization is performed at an optimum quantization step conforming to the picture in the block in such a manner that picture portions having the same level may remain at the same level after re-quantization. This renders it possible to eliminate quantization distortions from being produced in the reproduced picture.
Inventors
- 👤 Tetsujiro Kondo
- 👤 Kunio Kawaguchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:23
CPC Classifications
H; H04; H04N; H04N19/00; H04N19/42; H04N19/90; H04N19/98; H04N19/10; H04N19/102; H04N19/124
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
197 words
An adaptive dynamic range encoding device for quantized picture information comprising: re-quantization means, for re-quantizing the quantized picture information supplied thereto on the basis of blocks each consisting of a pre-set number of pixels for forming re-quantized output picture information; evaluation means for detecting changes in a spatial direction of a picture based on the quantized picture information supplied thereto and the re-quantized output picture information from said re-quantization means and outputting detected changes as evaluation information; memory means for storing the evaluation information from said evaluation means; comparator means for comparing new evaluation information from said evaluation means and temporally previous evaluation information read from said memory means to form output comparison information; and control means for controlling said memory means for storing therein a smaller value between the output comparison information supplied from said comparator means and the temporally previous evaluation information read from said memory means, said control means also controlling said re-quantization means to perform re-quantization of the quantized picture information for each block being re-quantized based on the evaluation information stored in said memory means when an arithmetic and logical operation of evaluation for each block is completed in said evaluation means.
Claim 2
Dependent Claim
197 words
An adaptive dynamic range encoding device for quantized picture information comprising: re-quantization means, for re-quantizing the quantized picture information supplied thereto on the basis of blocks each consisting of a pre-set number of pixels for forming re-quantized output picture information; evaluation means for detecting changes in a spatial direction of a picture based on the quantized picture information supplied thereto and the re-quantized output picture information from said re-quantization means and outputting detected changes as evaluation information; memory means for storing the evaluation information from said evaluation means; comparator means for comparing new evaluation information from said evaluation means and temporally previous evaluation information read from said memory means to form output comparison information; and control means for controlling said memory means for storing therein a smaller value between the output comparison information supplied from said comparator means and the temporally previous evaluation information read from said memory means, said control means also controlling said re-quantization means to perform re-quantization of the quantized picture information for each block being re-quantized based on the evaluation information stored in said memory means when an arithmetic and logical operation of evaluation for each block is completed in said evaluation means.
Claim 3
Dependent Claim
80 words
The adaptive dynamic range encoding device as claimed in claim 1 wherein said evaluation information is found using an equation P.sub.1 =W1·|x-x'|+Σ|W2 (d-d')| where P 1 is the evaluation information, W1 and W1 are pre-set coefficients, x denotes the value of a pixel to be worked on in the block, x' the value of the pixel after the re-quantization, d a difference between the pixel and a pixel adjacent thereto and d' the value of the difference d after re-quantization.
Claim 4
Dependent Claim
96 words
An adaptive dynamic range encoding method comprising: re-quantizing quantized input picture information on the basis of blocks each consisting of a pre-set number of pixels for forming re-quantized picture information; detecting spatial direction changes of pictures based on said quantized input picture information and the re-quantized picture information and forming evaluation information; comparing new evaluation information and temporally previous evaluation information and storing a smaller value between the new evaluation information and the temporally previous evaluation information; and re-quantizing the block-based quantized picture information, based on the stored evaluation information when the block-based evaluation is completed.
Claim 5
Dependent Claim
96 words
An adaptive dynamic range encoding method comprising: re-quantizing quantized input picture information on the basis of blocks each consisting of a pre-set number of pixels for forming re-quantized picture information; detecting spatial direction changes of pictures based on said quantized input picture information and the re-quantized picture information and forming evaluation information; comparing new evaluation information and temporally previous evaluation information and storing a smaller value between the new evaluation information and the temporally previous evaluation information; and re-quantizing the block-based quantized picture information, based on the stored evaluation information when the block-based evaluation is completed.
Claim 6
Dependent Claim
82 words
The adaptive dynamic range encoding device as claimed in claim 3 wherein the evaluation information P 1 is found using an equation P.sub.1 =W1·|x-x'|+Σ|W2 (d-d')| where P 1 is the evaluation information, W1 and W2 are pre-set coefficients, x denotes the value of a pixel to be worked on in the block, x' the value of the pixel after the re-quantization, d a difference between the pixel and a pixel adjacent thereto and d' the value of the difference d after re-quantization.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-08-21 | 1999-02-20 | 1999-08-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-08-21 | 2003-02-20 | 2003-08-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-08-21 | 2007-02-20 | 2007-08-22 | $7700.00 | Window Closed / Lapsed |