Image analysis – Image enhancement or restoration – Intensity – brightness – contrast – or shading correction
Reexamination Certificate
1998-09-23
2001-05-15
Rogers, Scott (Department: 2624)
Image analysis
Image enhancement or restoration
Intensity, brightness, contrast, or shading correction
C382S199000, C382S176000, C382S203000, C382S319000, C358S461000, C358S464000
Reexamination Certificate
active
06233363
ABSTRACT:
This application is based on Patent Application No. 92-62114 filed in Japan, the contents of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
This invention relates to an image reading apparatus for photographing a document such as a book which is placed face up, and especially to an art for reading out an image of the document with accuracy.
Conventionally, as to the image reading apparatus for the document placed face up, there has been provided an apparatus which detects an image including both of a finger pressing the document and the finger shadow (the image of this kind is hereinafter referred to as finger area) out of an image which is read out by an image reading sensor based on a brightness difference between a brightness of a document ground and a brightness of a finger area, and erases the finger area from the read-out image (e.g., refer to U.S. Pat. No. 5,377,019). On the other hand, there has also been provided an apparatus which detects marginal spaces in right and left edges of the document (blank area other than the area having letters and photographs, or other than the finger area), and erases an image outside the marginal spaces from a read-out image, thereby erases the image of the finger area which is normally positioned outside the marginal spaces (e.g., refer to U.S. Pat. No. 5,677,776)
However, in the above-mentioned conventional image reading apparatus, there has been a problem that a letter image lying into a finger shadow of the finger area is erroneously erased in the image erasure operation for the finger area since such a letter image cannot be distinguished and isolated from the finger area.
SUMMARY OF THE INVENTION
This invention is made to solve the above-mentioned problem. One object of the present invention is to provide an image reading apparatus in which an image of the finger area is precisely erased in the image erasure operation for the finger area, and in which the letter image lying into the finger shadow of the finger area is prevented from being erased.
In order to achieve the above-mentioned object, in accordance with the present invention, an image reading apparatus for reading out images from above a document table upon which a document is placed in a state that a surface having an image to be read out faces upward, said image reading apparatus comprises: a reading unit which reads out the image of the document to obtain image data; and, a processor which carries out processing of: detecting a finger area which corresponds with a finger and a shadow of the finger on the document, out of the image data which is obtained by said reading unit; detecting pixels on a boundary of the above-detected finger area; detecting pixels having brightness which corresponds with a letter from among the above-detected pixels on the boundary of the finger area; detecting a group of the pixels which corresponds with the letter in the finger area by starting at the above-detected pixels which correspond with the letter, and repeatedly linking the above-detected pixels with pixels having brightness which corresponds with the letter from among pixels in close to the above-detected pixels in the finger area; and, subjecting the image data which is obtained by said reading unit to a processing for erasing the finger area except the above-detected group of the pixels.
Also, in accordance with the present invention, a method of a data processing in an image reading apparatus for reading out images from above a document table upon which a document is placed in a state that a surface having an image to be read out faces upward, said method of a data processing comprises: (1) a step of obtaining image data by reading out an image of the document; (2) a step of detecting a finger area which corresponds with a finger and a shadow of the finger on the document out of the image data which is obtained in the step (1); (3) a step of detecting pixels on a boundary of the finger area which is detected in the step (2); (4) a step of detecting pixels having brightness which corresponds with a letter from among the pixels on the boundary of the finger area which are detected in the step (3); (5) a step of detecting a group of the pixels which corresponds with the letter in the finger area by starting at the pixels detected in the step (4) which correspond with the letter, and repeatedly linking the above-detected pixels with pixels having brightness which corresponds with the letter from among pixels in close to the above-detected pixels in the finger area; (6) a step of obtaining image data by reading out the image of the document once more; and, (7) a step of subjecting the image data which is obtained in the step (6) to a processing for erasing the finger area which is detected in the step (2) except the group of the pixels which is detected in the step (5).
REFERENCES:
patent: 4435836 (1984-03-01), Rubin
patent: 5048096 (1991-09-01), Beato
patent: 5377019 (1994-12-01), Okisu et al.
patent: 5608547 (1997-03-01), Nakatani et al.
patent: 5677776 (1997-10-01), Matsuda et al.
patent: 5841903 (1998-11-01), Kikuchi
patent: 5969795 (1999-10-01), Honda
patent: 6001635 (2000-01-01), Bungo et al.
Minolta Co. , Ltd.
Rogers Scott
Sidley & Austin
LandOfFree
Image reading apparatus for a document placed face up having... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Image reading apparatus for a document placed face up having..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Image reading apparatus for a document placed face up having... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2542655