Image analysis – Color image processing
Reexamination Certificate
1998-09-21
2001-10-23
Moore, David (Department: 2624)
Image analysis
Color image processing
C358S500000
Reexamination Certificate
active
06307960
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention pertains to a color image reading apparatus and a color image reading method to read color images, and more particularly, to a color image reading apparatus and a color image reading method in which scanning speed can be changed.
2. Description of the Related Art
In recent years, color image reading apparatuses that scan the image of an original document to read a color image and that can change speed of said scanning have been developed. The apparatuses are made capable of changing the scanning speed in order to meet mutually incompatible demands, i.e., to obtain a desired image quality and to improve the efficiency of the image input operation.
For example, where an extremely fine image is to be input, the scanning speed is set to be slow (image quality priority mode) to improve the reproducibility of fine lines. On the other hand, where a simple image for which fine line reproducibility is not an issue is input, the scanning speed is set to be fast (speed priority mode) to improve image input operation efficiency.
When the scanning speed is changed in this way, the amount of light received by the sensor changes from one speed to another, and the signal level (image data value) output from the sensor also changes. Therefore, the sensor output is corrected such that it becomes constant regardless of whether the scanning speed is set to slow or to fast.
However, in a conventional color image reading apparatus of this type, only the output correction mentioned above is performed based on the scanning speed, and therefore, a problem arises in the color reproducibility of the color image.
In other words, the problem arises that, when identical color masking conversion is carried out for images scanned using different speeds, a discrepancy or color imbalance occurs between the colors of the image read and the colors of the printed image, reducing the color reproducibility.
OBJECTS AND SUMMARY
The present invention was made in order to resolve the problem with conventional devices described above. Its object is to provide an improved color image reading apparatus or an improved color image reading method.
Another object of the present invention is to provide a color image reading apparatus or a color image reading method that maintains good color reproducibility when the scanning speed of the scanner is changed.
Yet another object of the present invention is to provide a color image reading apparatus or a color image reading method that changes the conversion parameters (matrix) for the color masking conversion in response to the scanning speed and in which color reproducibility does not change when the scanning speed of the scanner is changed.
In order to attain at least one of these and other objects, the color image reading apparatus of the present invention comprises: a scanner which scans an image to read the image and which outputs color image signals, said scanner being able to scan the image with at least two scanning speed; a color masking unit which converts the color image signals output from said scanner into print data corresponding to the print colors using conversion parameters; and a selector which alternates the conversion parameters used by the color masking unit in response to the scanning speed of the scanner.
According to another aspect of the present invention, an image processing apparatus for processing color image signals of an image originally scanned by a scanner comprises: a selector which selects one of conversion parameters in response to an input data, the input data representing at least one scanning speed of the scanner; and a color masking unit which converts the color image signals into output data for representing an image corresponding to the image signals, said color masking unit converting the image signals by using the conversion parameter selected by said selector.
REFERENCES:
patent: 5719613 (1998-02-01), Fukui et al.
patent: 5737100 (1998-04-01), Funada
patent: 5768403 (1998-06-01), Suzuki
Burns Doane , Swecker, Mathis LLP
Minolta Co. , Ltd.
Moore David
Worku Negussie
LandOfFree
Color image reading apparatus and color image reading method does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Color image reading apparatus and color image reading method, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Color image reading apparatus and color image reading method will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2603331