Abstract: An edge image generating unit detects edge pixels in an original image and generates an edge image that includes the detected edge pixels. A reduction processing unit sets a reduction direction as a horizontal or a vertical direction, and reduces the edge image along the reduction direction by a predetermined reduction ratio without reducing the original image along a direction perpendicular to the reduction direction and thereby generates a reduced image. A connecting pixel group detecting unit detects, in the reduced image, a connecting pixel group continuously extending along the reduction direction. A ruled line determining unit associates two connecting pixel groups with each other as a connecting pixel group pair among the detected connecting pixel groups, and determines a position of a ruled line in the original image from a position of the connecting pixel group pair on the basis of the reduction ratio.

Abstract: An edge image generating unit detects edge pixels in an original image and generates an edge image that includes the detected edge pixels. A reduction processing unit sets a reduction direction as a horizontal or a vertical direction, and reduces the edge image along the reduction direction by a predetermined reduction ratio without reducing the original image along a direction perpendicular to the reduction direction and thereby generates a reduced image. A connecting pixel group detecting unit detects, in the reduced image, a connecting pixel group continuously extending along the reduction direction. A ruled line determining unit associates two connecting pixel groups with each other as a connecting pixel group pair among the detected connecting pixel groups, and determines a position of a ruled line in the original image from a position of the connecting pixel group pair on the basis of the reduction ratio.

Abstract: An image processing apparatus includes a reduction processing unit, a connecting pixel group detecting unit, and a ruled line determining unit. The reduction processing unit is configured to (a) set a reduction direction as one of a horizontal direction and a vertical direction, and (b) reduce an original image along the reduction direction by a predetermined reduction ratio without reducing the original image along a direction perpendicular to the reduction direction and thereby generate a reduced image. The connecting pixel group detecting unit is configured to detect a connecting pixel group in the reduced image, the connecting pixel group continuously extending along the reduction direction. The ruled line determining unit is configured to determine a position of a ruled line in the original image from a position of the connecting pixel group in the reduced image on the basis of the reduction ratio.

Abstract: An image processing apparatus includes an area extracting unit and a table image detecting unit. The area extracting unit is configured to extract halftone dot areas and character images in an image. The table image detecting unit is configured to detect the extracted halftone dot areas as a table image if (a) the extracted halftone dot areas include no ruled lines, (b) plural halftone dot areas among the extracted halftone dot areas are arrayed in a primary scanning direction and/or a secondary scanning direction, and (c) the arrayed plural halftone dot areas include the character images at at least two positions.

Abstract: An image processing apparatus includes an area extracting unit and a table image detecting unit. The area extracting unit is configured to extract a halftone dot area and character images in an image. The table image detecting unit is configured to detect the extracted halftone dot area as a table image if (a) the extracted halftone dot area includes no ruled lines and (b1) at least two of the detected character images are arranged in a primary scanning direction or a secondary scanning direction in the halftone dot area and (b2) character alignment of a tabular layout is detected on the character images on the basis of positional relations between divisional areas into which the halftone dot area is equally divided and the character images.

Abstract: An image processing apparatus includes a reduction processing unit, a connecting pixel group detecting unit, and a ruled line determining unit. The reduction processing unit is configured to (a) set a reduction direction as one of a horizontal direction and a vertical direction, and (b) reduce an original image along the reduction direction by a predetermined reduction ratio without reducing the original image along a direction perpendicular to the reduction direction and thereby generate a reduced image. The connecting pixel group detecting unit is configured to detect a connecting pixel group in the reduced image, the connecting pixel group continuously extending along the reduction direction. The ruled line determining unit is configured to determine a position of a ruled line in the original image from a position of the connecting pixel group in the reduced image on the basis of the reduction ratio.

Abstract: An image processing apparatus includes an area extracting unit and a table image detecting unit. The area extracting unit is configured to extract a halftone dot area and character images in an image. The table image detecting unit is configured to detect the extracted halftone dot area as a table image if (a) the extracted halftone dot area includes no ruled lines and (b1) at least two of the detected character images are arranged in a primary scanning direction or a secondary scanning direction in the halftone dot area and (b2) character alignment of a tabular layout is detected on the character images on the basis of positional relations between divisional areas into which the halftone dot area is equally divided and the character images.

Abstract: An image processing apparatus includes an area extracting unit, a specific halftone dot area detecting unit, and an encoding unit. The area extracting unit extracts a halftone dot area from an image. The specific halftone dot area detecting unit detects a specific halftone dot area, the specific halftone dot area being the extracted halftone dot area that includes a character and of which a variation range in a distribution of luminance and hue is less than a predetermined range. The encoding unit encodes the specific halftone dot area in an encoding manner different from an encoding manner for the halftone dot area other than the specific halftone dot area, the encoding manner for the specific halftone dot area providing higher image quality after encoding than image quality provided by the encoding manner for the halftone dot area other than the specific halftone dot area.

Abstract: An edge image generating unit detects edges in an original image and generates an edge image from the edges. A connection pixel extracting unit extracts connection pixel sets in the edge image. A binary image generating unit classifies colors of the connection pixel sets into a predetermined number of achromatic target colors and a predetermined number of chromatic target colors if a color mode is set as color, and classifies the colors of the connection pixel sets into a predetermined number of achromatic target colors if the color mode is set as monochrome, where the number of the achromatic target colors set in the color mode of monochrome is larger than the number of the achromatic target colors in the color mode of color.

Abstract: An image processing apparatus includes an area extracting unit and a table image detecting unit. The area extracting unit is configured to extract halftone dot areas and character images in an image. The table image detecting unit is configured to detect the extracted halftone dot areas as a table image if (a) the extracted halftone dot areas include no ruled lines, (b) plural halftone dot areas among the extracted halftone dot areas are arrayed in a primary scanning direction and/or a secondary scanning direction, and (c) the arrayed plural halftone dot areas include the character images at at least two positions.

Abstract: An image processing apparatus includes an area extracting unit, a specific halftone dot area detecting unit, and an encoding unit. The area extracting unit extracts a halftone dot area from an image. The specific halftone dot area detecting unit detects a specific halftone dot area, the specific halftone dot area being the extracted halftone dot area that includes a character and of which a variation range in a distribution of luminance and hue is less than a predetermined range. The encoding unit encodes the specific halftone dot area in an encoding manner different from an encoding manner for the halftone dot area other than the specific halftone dot area, the encoding manner for the specific halftone dot area providing higher image quality after encoding than image quality provided by the encoding manner for the halftone dot area other than the specific halftone dot area.

Abstract: An image reading device includes a platen glass, a document feeder, a light source, a light receiving section, a first opening/closing detection sensor, a second opening/closing detection sensor, and a document size determination section. The document size determination section determines a size of an original document on the basis of a measurement result from the light receiving section. Where the first opening/closing detection sensor indicates the open state, while the second opening/closing detection sensor indicates no open state when the original document is placed on the platen glass, the document size determination section determines a size of the original document in a main scanning direction on the basis of full lighting-up determination data obtained with all of plural light emitting elements lighted up and partial lighting-up determination data obtained with some of the plural light emitting elements lighted up.

Abstract: An edge image generating unit detects edges in an original image and generates an edge image from the edges. A connection pixel extracting unit extracts connection pixel sets in the edge image. A binary image generating unit classifies colors of the connection pixel sets into a predetermined number of achromatic target colors and a predetermined number of chromatic target colors if a color mode is set as color, and classifies the colors of the connection pixel sets into a predetermined number of achromatic target colors if the color mode is set as monochrome, where the number of the achromatic target colors set in the color mode of monochrome is larger than the number of the achromatic target colors in the color mode of color.

Abstract: An image reading device includes a platen glass, a document feeder, a light source, a light receiving section, a first opening/closing detection sensor, a second opening/closing detection sensor, and a document size determination section. The document size determination section determines a size of an original document on the basis of a measurement result from the light receiving section. Where the first opening/closing detection sensor indicates the open state, while the second opening/closing detection sensor indicates no open state when the original document is placed on the platen glass, the document size determination section determines a size of the original document in a main scanning direction on the basis of full lighting-up determination data obtained with all of plural light emitting elements lighted up and partial lighting-up determination data obtained with some of the plural light emitting elements lighted up.