Patent ID: 6122077
Filing Date: 2000-09-19
Classification: H04N

Abstract:
An image scanner comprising:read means for reading image data on a document; andsignal processing means for producing image data by subjecting image data read by said read means to predetermined operations,wherein said signal processing means has a data signal generating circuit to produce image data by subjecting image data read by said read means to predetermined processing, a resolution enhancement circuit to produce binarized image data by subjecting image data formed by said data signal generating circuit to predetermined operations,wherein said resolution enhancement circuit has an enhancement and interpolation circuit to produce enhanced and interpolated image data by subjecting image data read by said read means to enhancement processing and interpolation processing, a floating slice circuit to obtain a floating slice level whose level fluctuates in accordance with image data values in the vicinity of said image data read by said read means, and a binarization and density conversion circuit to produce binarized image data by binarizing said enhanced and interpolated data from said enhancement and interpolation circuit using said floating slice level from said floating slice level, andwherein said binarization and density conversion circuit detects isolated points in said enhance and interpolated image data sent from said enhancement and interpolation circuit, and when data existing at said isolated points are subject to discarding, changes the locations of such data in said enhanced and interpolated image data to prevent data existing at said isolated points from being discarded.