Image reduction conversion method

Claim 2

A computer-implemented image data reduction and image conversion method for an image consisting of a plurality of pixels, at a reduction ratio of 1/N, wherein N is a positive integer greater than or equal to 2, the computer-implemented image data reduction and image conversion method comprising the steps of: determining values for the shortest distance from a center pixel to each of the other pixels in an image to be converted; detecting in the image a first aggregation of pixels or a second aggregation of pixels in a reference area of the image, wherein said first aggregation has a vertical length equal to or greater than L pixels and a horizontal width less than N pixels, wherein L is an integer greater than or equal to 3, and said second aggregation has a vertical length less than N pixels and a horizontal width equal to or greater than L pixels, wherein said reference area includes pixels surrounding said center pixel; setting a value for each pixel in said image as at least one of (1) a pixel value of the determined value of the shortest distance from each pixel to said center pixel if no first aggregation of pixels has been detected, (2) a value of said detected first aggregation of pixels if the first aggregation of pixels has been detected, and (3) a value different from the value of the shortest distance from each pixel to said center pixel if both the first aggregation of pixels and the second aggregation of pixels have been detected; and storing in a storage medium the reduced image data representing a converted image.

Claim 3

The computer-implemented image data reduction and image conversion method according to claim 1, wherein said center pixel is not a portion of said first or second aggregation and a centroid of said first or second aggregation is a region consisting of a square of N×N pixels centered at said center pixel.

Claim 4

The computer-implemented image data reduction and image conversion method according to claim 2, wherein said reference area is a union of a first region and a second region excluding said center pixel, said first region having a length of L pixels in the vertical direction and a width of 2N pixels in the horizontal direction, and said second region having a width of L pixels in the horizontal direction and a length of 2N pixels in the vertical direction.

Claim 5

The computer-implemented image data reduction and image conversion method according to claim 1, further including the step of: reading out the stored reduced image data for display of the converted image.

Claim 6

A computer-implemented image data reduction and image conversion method for a black and white image consisting of a plurality of original pixels, each original pixel being either black or white, said data reduction and image conversion performed at a reduction ratio of 1/N, N being a positive integer greater than 1, the computer-implemented image data reduction and image conversion method comprising the steps of: determining a value for a shortest average distance from a center pixel to the original pixels consisting of the image to be converted; defining a reference area around the original center pixel; determining whether a first kind of aggregation of pixels exists in the reference area, said first kind of aggregation being an assembly of either black or white pixels covering an area having a vertical length equal to or larger than L pixels and a horizontal width less than N pixels, and whether a second kind of aggregation of pixels exists in the reference area, said second kind of aggregation being an assembly of either black or white pixels covering an area having a vertical length less than N pixels and a horizontal width equal to or larger than L pixels, wherein L is 3; determining a value representing the reference area as being at least one of (1) the value of said original center pixel if neither the first nor the second kind of aggregation is determined to exist, (2) a value of said first or second kind of aggregation if one of the two is determined to exist, and (3) a value different from the value of said original center pixel if both of the first and the second kinds of aggregations are determined to exist; outputting the value representing the reference area; and storing the outputted value with data for pixels outside the reference area as reduced image data for a converted image.

Claim 7

A computer-implemented image data reduction and image conversion method for a black and white image consisting of a plurality of original pixels, each original pixel being either black or white, said data reduction and image conversion performed at a reduction ratio of 1/N, N being a positive integer greater than 1, the computer-implemented image data reduction and image conversion method comprising the steps of: determining a value for a shortest average distance from a center pixel to the original pixels consisting of the image to be converted; defining a reference area around the original center pixel; determining whether a first kind of aggregation of pixels exists in the reference area, said first kind of aggregation being an assembly of either black or white pixels covering an area having a vertical length equal to or larger than L pixels and a horizontal width less than N pixels, and whether a second kind of aggregation of pixels exists in the reference area, said second kind of aggregation being an assembly of either black or white pixels covering an area having a vertical length less than N pixels and a horizontal width equal to or larger than L pixels, wherein L is 3; determining a value representing the reference area as being at least one of (1) the value of said original center pixel if neither the first nor the second kind of aggregation is determined to exist, (2) a value of said first or second kind of aggregation if one of the two is determined to exist, and (3) a value different from the value of said original center pixel if both of the first and the second kinds of aggregations are determined to exist; outputting the value representing the reference area; and storing the outputted value with data for pixels outside the reference area as reduced image data for a converted image.

Claim 8

The computer-implemented image data reduction and image conversion method according to claim 5, further including the step of: reading out the stored reduced image data for display of the converted image without loss of fine lines in the converted image.

Claim 9

A high-speed binary-image processor for data-reducing images consisting of a plurality of pixels, the processor comprising: means for receiving an input data of binary-image type; a reduction operator for reducing the input data, including: means for selecting a center pixel of an image represented by the input data by comparing pixels within a first region of the image with the pixels in a second region of the image, wherein the first region consists of L pixels in the vertical direction and 2N pixels in the horizontal direction and the second region consists of 2N pixels in the vertical direction and L pixels in the horizontal direction, L being an integer greater than or equal to 3 and N being an integer greater than or equal to 2; means for detecting a fine line in the image, wherein the fine line is one of a vertical aggregation of concordant pixels in the input binary-image and a diagonal aggregation of concordant pixels in the image, wherein pixels are concordant when consisting of white pixels together or black pixels together, the center pixel not being one of the concordant pixels of the vertical aggregation or the diagonal aggregation, and means for identifying a converted pixel of the fine line, which is a pixel along a line of pixels intersecting the fine line and including the center pixel of the input binary-image, and for converting the converted pixel to a value corresponding to the center pixel of the image if the detecting means detects a fine line with a converted pixel having a value different from the value of the center pixel of the image; and means for outputting reduced data for a converted image including the converted centroid pixel.

Claim 10

A high-speed binary-image processor for data-reducing images consisting of a plurality of pixels, the processor comprising: means for receiving an input data of binary-image type; a reduction operator for reducing the input data, including: means for selecting a center pixel of an image represented by the input data by comparing pixels within a first region of the image with the pixels in a second region of the image, wherein the first region consists of L pixels in the vertical direction and 2N pixels in the horizontal direction and the second region consists of 2N pixels in the vertical direction and L pixels in the horizontal direction, L being an integer greater than or equal to 3 and N being an integer greater than or equal to 2; means for detecting a fine line in the image, wherein the fine line is one of a vertical aggregation of concordant pixels in the input binary-image and a diagonal aggregation of concordant pixels in the image, wherein pixels are concordant when consisting of white pixels together or black pixels together, the center pixel not being one of the concordant pixels of the vertical aggregation or the diagonal aggregation, and means for identifying a converted pixel of the fine line, which is a pixel along a line of pixels intersecting the fine line and including the center pixel of the input binary-image, and for converting the converted pixel to a value corresponding to the center pixel of the image if the detecting means detects a fine line with a converted pixel having a value different from the value of the center pixel of the image; and means for outputting reduced data for a converted image including the converted centroid pixel.