Quantization step size adjusting circuit using edge detections

Details Quantization step size adjusting circuit using edge detections Quantization step size adjusting circuit using edge detections

1991-10-15

1996-02-13

Couso, Yon J.

Image analysis

Image compression or coding

Quantization

382254, 348405, 358426, G06K 938

Patent

active

054917611

ABSTRACT:
A quantization step size adjusting circuit using edge detection techniques for adjusting quantization step sizes in sampling an image signal to provide a digital signal by controlling an image compression ratio in dependence upon a pixel density representation (levels of sophistication) of an image. The quantization step size adjusting circuit comprises a coordinate converter for providing the image signal representative of a luminance signal and color difference signals, an edge detector for detecting edge values representative of peripheral pixels of a plurality of addresses of the image signal designated by control signals, a block formatting circuit for formatting the image signal into a plurality of image blocks having a predetermined size of pixels, and a circuit for controlling quantization step sizes of the image signal in dependence upon a determination edge values representative of peripheral pixels of a plurality of addresses of the image signal designated by the control signals and a determination of a selected scale factor in accordance with the pixel density representation of the image.

REFERENCES:
patent: 4677479 (1987-06-01), Hatori et al.
patent: 4734767 (1988-03-01), Kaneko et al.
patent: 4920426 (1990-04-01), Hatori et al.
patent: 5051840 (1991-09-01), Watanabe et al.
patent: 5113256 (1992-05-01), Citta et al.
patent: 5121216 (1992-06-01), Chen et al.
patent: 5126857 (1992-06-01), Watanabe et al.
patent: 5150433 (1992-09-01), Daly
patent: 5170264 (1992-12-01), Saito et al.
patent: 5309253 (1994-05-01), Ariga et al.
patent: 5345517 (1994-09-01), Katayama et al.

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