Image analysis – Image enhancement or restoration – Intensity – brightness – contrast – or shading correction
Patent
1993-11-05
1997-04-15
Couso, Yon J.
Image analysis
Image enhancement or restoration
Intensity, brightness, contrast, or shading correction
358455, G06K 938
Patent
active
056218257
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
This invention relates to an image processor and an image processing method for performing pattern-matching processing and the like for the purpose of object recognition, as well as to an apparatus which applies the same.
BACKGROUND ART
A technique available for pattern matching involves setting a window on image data obtained by imaging a subject, and calculating degree of coincidence or degree of similarity between partial image data within the window and standard image data registered in advance. By executing the above-described processing with regard to the window at each position thereof while the window is made to scan within a picture, a window containing partial image data exhibiting the highest degree of coincidence or similarity is detected, thereby making it possible to recognize a position at which an image identical or similar to the standard image exists. Thus, measurement processing of various types can be executed with regard to image data within a specified window.
Image data generally is represented by eight or more bits per pixel. Line memories are used in order to extract image data within a set window at a video rate. The line memories, the number of which corresponds to the number of pixels in the vertical direction of the window, are connected in cascade, and image data is transferred among the line memories in synchronism with a clock signal. By extracting image data at a single stroke from a prescribed position of each line memory, e.g., the terminus of the line memory, one column of image data in the vertical direction of the window is obtained.
In an image processor having such a configuration, a problem encountered is that a large number of line memories of at least eight bits each must be provided, as a result of which there is an increase in the scale of hardware. Further, pattern-matching processing of eight bits per pixel is required. When this is implemented by hardware, the scale of circuitry is similarly increased. If it is attempted to implement the foregoing by software, more complicated processing results.
DISCLOSURE OF THE INVENTION
A main object of the present invention is to provide an image processor and an image processing method through which hardware can be reduced in scale.
Another object of the present invention is to simplify pattern-matching processing.
A further object of the present invention is to provide various applications of the image processor.
An image processor according to the present invention comprises pseudo-gray-scale image generating circuit means for converting input image data, which is represented by a first prescribed number of bits per pixel, into pseudo-gray-scale image data represented by a second prescribed number of bits, which is less than the first prescribed number of bits, image restoration circuit means for restoring the pseudo-gray-scale image data for each and every one of a plurality of small areas, each of which comprises a plurality of pixels and is provided in a window that scans the pseudo-gray-scale image generated by the pseudo-gray-scale image generating circuit means, with each small area serving as one restored pixel, and outputting restored image data for a window at each and every position, and similarity operating circuit means for calculating an index value representing a degree of similarity between the restored image data of each window sequentially outputted by the image restoration circuit means and text data representing a standard image set in advance.
An image processing method according to the present invention comprises converting input image data, which is represented by a first prescribed number of bits per pixel, into pseudo-gray-scale image data represented by a second prescribed number of bits, which is less than the first prescribed number of bits, summing the pseudo-gray-scale image data for each and every one of a plurality of small areas, each of which comprises a plurality of pixels and is provided in a window that scans the pseudo-gray-scale image generated, thereby rest
REFERENCES:
patent: 3898617 (1975-08-01), Kashioka
patent: 4581762 (1986-04-01), Lapidus et al.
patent: 4709274 (1987-11-01), Tanoika
patent: 4821334 (1989-04-01), Ogino et al.
patent: 5150428 (1992-09-01), Leone et al.
patent: 5260810 (1993-11-01), Kanno et al.
patent: 5267330 (1993-11-01), Masuda
patent: 5317653 (1994-05-01), Eschbach et al.
Kato Yutaka
Masaki Toshimichi
Couso Yon J.
Omron Corporation
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