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US 6,636,630 B1Granted
Image-processing apparatus
AssigneeSharp Kabushiki Kaisha
InventorsYasushi Adachi, Toshihiro Kanata
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Abstract
An area-separation processing section, installed in an image-processing apparatus of the present invention, is provided with a block memory A for storing image signals, a maximum/minimum pixel detection section, a maximum/minimum pixel feature-amount calculation section and a maximum/minimum pixel classifying section that make a judgment as to what kind of maximum pixel or minimum pixel a target pixel A within the block memory A forms, a block memory B for storing classifying signals outputted from the maximum/minimum pixel classifying section, and a mesh feature-amount calculation section and a mesh judgment section that make a judgment as to whether or not a target pixel B within the block memory B belongs to a mesh area
Claims24
An image-processing apparatus, which deals with an image signal obtained for each pixel by scanning a document and discriminates the pixel as to which area it is located, a character area, a photograph area or a mesh area, characterized by comprising:
- a first block memory for storing image signals of a first local block consisting of a pixel that is designated as a first target pixel and a plurality of pixels on the periphery of the first target pixel;
- a maximum/minimum pixel detection section which makes a judgment as to whether the first target pixel is a maximum pixel that gives a maximum density value in the first local block or a minimum pixel that gives a minimum density value therein by using the image signals stored in the first block memory;
- a maximum/minimum pixel feature-amount calculation section which calculates information as to density changes from the first target pixel to the peripheral pixels within the local block by using the image signals stored in the first block memory;
- a maximum/minimum pixel classifying section which classifies the first target pixel by using a classifying signal obtained based upon outputs from the maximum/minimum pixel detection section and the maximum/minimum pixel feature-amount calculation section, respectively;
- a second block memory for storing classifying signals outputted from the maximum/minimum pixel classifying section with respect to a second local block consisting of a pixel that is designated as a second target pixel and a plurality of pixels on the periphery of the second target pixel;
- a mesh feature-amount calculation section for calculating the amount of feature of the second target pixel by using the classifying signals of the second local block stored in the second block memory;
- and
- a mesh judgment section which makes a judgment as to whether or not the second target pixel is a pixel belonging to a mesh area by using the amount of feature calculated by the mesh feature-amount calculation section , wherein said maximum/minimum pixel detection section makes a judgment as to whether the first target pixel is the maximum or minimum pixel in the first local block, based upon the average density value of pixels within the first local block, the result of density comparisons between the density value of the first target pixel and density values of the pixels within the first local block, the sum of density coincident pixels that is a total number of pixels within the first local block having density values coincident with the density value of the first target pixel, and the sum of density differences that is a sum of the absolute values of differences between the density value of the first target pixel and density values of the peripheral pixels within the first local block.
5 more elements
An image-processing apparatus, which deals with an image signal obtained for each pixel by scanning a document and discriminates the pixel as to which area it is located, a character area, a photograph area or a mesh area, characterized by comprising:
- a first block memory for storing image signals of a first local block consisting of a pixel that is designated as a first target pixel and a plurality of pixels on the periphery of the first target pixel;
- a maximum/minimum pixel detection section which makes a judgment as to whether the first target pixel is a maximum pixel that gives a maximum density value in the first local block or a minimum pixel that gives a minimum density value therein by using the image signals stored in the first block memory;
- a maximum/minimum pixel feature-amount calculation section which calculates information as to density changes from the first target pixel to the peripheral pixels within the local block by using the image signals stored in the first block memory;
- a maximum/minimum pixel classifying section which classifies the first target pixel by using a classifying signal obtained based upon outputs from the maximum/minimum pixel detection section and the maximum/minimum pixel feature-amount calculation section, respectively;
- a second block memory for storing classifying signals outputted from the maximum/minimum pixel classifying section with respect to a second local block consisting of a pixel that is designated as a second target pixel and a plurality of pixels on the periphery of the second target pixel;
- a mesh feature-amount calculation section for calculating the amount of feature of the second target pixel by using the classifying signals of the second local block stored in the second block memory;
- and
- a mesh judgment section which makes a judgment as to whether or not the second target pixel is a pixel belonging to a mesh area by using the amount of feature calculated by the mesh feature-amount calculation section,
- wherein, supposing that classifying signals applied to all of the maximum or minimum pixels extracted in the second local block are first classifying signals and that classifying signals applied to the maximum or minimum pixels that are supposed to belong to mesh areas are second classifying signals, the mesh feature-amount calculation section is designed to calculate the ratio of the total number of the pixels having the second classifying signals to the total number of the pixels having the first classifying signals, as the amount of feature.
6 more elements
An image-processing apparatus, which deals with an image signal obtained for each pixel by scanning a document and discriminates the pixel as to which area it is located, a character area, a photograph area or a mesh area, characterized by comprising:
- a first block memory for storing image signals of a first local block consisting of a pixel that is designated as a first target pixel and a plurality of pixels on the periphery of the first target pixel;
- a maximum/minimum pixel detection section which makes a judgment as to whether the first target pixel is a maximum pixel that gives a maximum density value in the first local block or a minimum pixel that gives a minimum density value therein by using the image signals stored in the first block memory;
- a maximum/minimum pixel feature-amount calculation section which calculates information as to density changes from the first target pixel to the peripheral pixels within the local block by using the image signals stored in the first block memory;
- a maximum/minimum pixel classifying section which classifies the first target pixel by using a classifying signal obtained based upon outputs from the maximum/minimum pixel detection section and the maximum/minimum pixel feature-amount calculation section, respectively;
- a second block memory for storing classifying signals outputted from the maximum/minimum pixel classifying section with respect to a second local block consisting of a pixel that is designated as a second target pixel and a plurality of pixels on the periphery of the second target pixel;
- a mesh feature-amount calculation section for calculating the amount of feature of the second target pixel by using the classifying signals of the second local block stored in the second block memory;
- and
- a mesh judgment section which makes a judgment as to whether or not the second target pixel is a pixel belonging to a mesh area by using the amount of feature calculated by the mesh feature-amount calculation section,
- wherein, with respect to each of a plurality of sub blocks formed by finely dividing the second block memory, the mesh feature-amount calculation section calculates the total number of pixels having third classifying signals that are specific classifying signals so that the number of the sub blocks in which the total number of pixels having the third classifying signals is in a predetermined range is calculated as the amount of feature.
6 more elements
An image-processing apparatus, which deals with an image signal obtained for each pixel by scanning a document and discriminates the pixel as to which area it is located, a character area, a photograph area or a mesh area, characterized by comprising:
- a first block memory for storing image signals of a first local block consisting of a pixel that is designated as a first target pixel and a plurality of pixels on the periphery of the first target pixel;
- a maximum/minimum pixel detection section which makes a judgment as to whether the first target pixel is a maximum pixel that gives a maximum density value in the first local block or a minimum pixel that gives a minimum density value therein by using the image signals stored in the first block memory;
- a maximum/minimum pixel feature-amount calculation section which calculates information as to density changes from the first target pixel to the peripheral pixels within the local block by using the image signals stored in the first block memory;
- a maximum/minimum pixel classifying section which classifies the first target pixel by using a classifying signal obtained based upon outputs from the maximum/minimum pixel detection section and the maximum/minimum pixel feature-amount calculation section, respectively;
- a second block memory for storing classifying signals outputted from the maximum/minimum pixel classifying section with respect to a second local block consisting of a pixel that is designated as a second target pixel and a plurality of pixels on the periphery of the second target pixel;
- a mesh feature-amount calculation section for calculating the amount of feature of the second target pixel by using the classifying signals of the second local block stored in the second block memory;
- and
- a mesh judgment section which makes a judgment as to whether or not the second target pixel is a pixel belonging to a mesh area by using the amount of feature calculated by the mesh feature-amount calculation section,
- wherein said maximum/minimum pixel feature-amount calculation section comprises a binarizing circuit for binarizing pixels within the first local block by using a predetermined threshold value, and a main-scanning-direction runlength-difference summing circuit which calculates the number of continuous pixels having the same value as the first target pixel in the main-scanning direction from the first target pixel, and also calculates the sum of the absolute values of differences between the density value of the target pixel and the density values of the peripheral pixels located in the main-scanning direction from the first target pixel, with respect to the binarized pixels.
6 more elements
An image-processing apparatus, which deals with an image signal obtained for each pixel by scanning a document and discriminates the pixel as to which area it is located, a character area, a photograph area or a mesh area, characterized by comprising:
- a first block memory for storing image signals of a first local block consisting of a pixel that is designated as a first target pixel and a plurality of pixels on the periphery of the first target pixel;
- a maximum/minimum pixel detection section which makes a judgment as to whether the first target pixel is a maximum pixel that gives a maximum density value in the first local block or a minimum pixel that gives a minimum density value therein by using the image signals stored in the first block memory;
- a maximum/minimum pixel feature-amount calculation section which calculates information as to density changes from the first target pixel to the peripheral pixels within the local block by using the image signals stored in the first block memory;
- a maximum/minimum pixel classifying section which classifies the first target pixel by using a classifying signal obtained based upon outputs from the maximum/minimum pixel detection section and the maximum/minimum pixel feature-amount calculation section, respectively;
- a second block memory for storing classifying signals outputted from the maximum/minimum pixel classifying section with respect to a second local block consisting of a pixel that is designated as a second target pixel and a plurality of pixels on the periphery of the second target pixel;
- a mesh feature-amount calculation section for calculating the amount of feature of the second target pixel by using the classifying signals of the second local block stored in the second block memory;
- and
- a mesh judgment section which makes a judgment as to whether or not the second target pixel is a pixel belonging to a mesh area by using the amount of feature calculated by the mesh feature-amount calculation section,
- wherein said maximum/minimum pixel feature-amount calculation section comprises a binarizing circuit for binarizing pixels within the first local block by using a predetermined threshold value, and a sub-scanning-direction runlength-difference summing circuit which calculates the number of continuous pixels having the same value as the first target pixel in the sub-scanning direction from the first target pixel, and also calculates the sum of the absolute values of differences between the density value of the target pixel and the density values of the peripheral pixels located in the sub-scanning direction from the first target pixel, with respect to the binarized pixels.
6 more elements
An image-processing apparatus, which deals with an image signal obtained for each pixel by scanning a document and discriminates the pixel as to which area it is located, a character area, a photograph area or a mesh area, characterized by comprising:
- a first block memory for storing image signals of a first local block consisting of a pixel that is designated as a first target pixel and a plurality of pixels on the periphery of the first target pixel;
- a maximum/minimum pixel detection section which makes a judgment as to whether the first target pixel is a maximum pixel that gives a maximum density value in the first local block or a minimum pixel that gives a minimum density value therein by using the image signals stored in the first block memory;
- a maximum/minimum pixel feature-amount calculation section which calculates information as to density changes from the first target pixel to the peripheral pixels within the local block by using the image signals stored in the first block memory;
- a maximum/minimum pixel classifying section which classifies the first target pixel by using a classifying signal obtained based upon outputs from the maximum/minimum pixel detection section and the maximum/minimum pixel feature-amount calculation section, respectively;
- a second block memory for storing classifying signals outputted from the maximum/minimum pixel classifying section with respect to a second local block consisting of a pixel that is designated as a second target pixel and a plurality of pixels on the periphery of the second target pixel;
- a mesh feature-amount calculation section for calculating the amount of feature of the second target pixel by using the classifying signals of the second local block stored in the second block memory;
- and
- a mesh judgment section which makes a judgment as to whether or not the second target pixel is a pixel belonging to a mesh area by using the amount of feature calculated by the mesh feature-amount calculation section,
- wherein the mesh feature-amount calculation section comprises:
- a granularity feature-amount calculation section which, supposing that classifying signals applied to all the maximum or minimum pixels extracted in the second local block are first classifying signals and that classifying signals applied to the maximum or minimum pixels that are supposed to belong to mesh areas are second classifying signals, calculates the ratio of the total number of the pixels having the second classifying signals to the total number of the pixels having the first classifying signals, as the amount of feature.
7 more elements
An image-processing apparatus, which deals with an image signal obtained for each pixel by scanning a document and discriminates the pixel as to which area it is located, a character area, a photograph area or a mesh area, characterized by comprising:
- a first block memory for storing image signals of a first local block consisting of a pixel that is designated as a first target pixel and a plurality of pixels on the periphery of the first target pixel;
- a maximum/minimum pixel detection section which makes a judgment as to whether the first target pixel is a maximum pixel that gives a maximum density value in the first local block or a minimum pixel that gives a minimum density value therein by using the image signals stored in the first block memory;
- a maximum/minimum pixel feature-amount calculation section which calculates information as to density changes from the first target pixel to the peripheral pixels within the local block by using the image signals stored in the first block memory;
- a maximum/minimum pixel classifying section which classifies the first target pixel by using a classifying signal obtained based upon outputs from the maximum/minimum pixel detection section and the maximum/minimum pixel feature-amount calculation section, respectively;
- a second block memory for storing classifying signals outputted from the maximum/minimum pixel classifying section with respect to a second local block consisting of a pixel that is designated as a second target pixel and a plurality of pixels on the periphery of the second target pixel;
- a mesh feature-amount calculation section for calculating the amount of feature of the second target pixel by using the classifying signals of the second local block stored in the second block memory;
- and
- a mesh judgment section which makes a judgment as to whether or not the second target pixel is a pixel belonging to a mesh area by using the amount of feature calculated by the mesh feature-amount calculation section,
- wherein the mesh feature-amount calculation section comprises a periodicity feature-amount calculation circuit which, with respect to each of a plurality of sub blocks formed by finely dividing the second block memory, calculates the total number of pixels having third classifying signals that are specific classifying signals so that the number of the sub blocks in which the total number of pixels having the third classifying signals is in a predetermined range is calculated as the amount of feature.
6 more elements
Dependencies are inferred from the claim text.