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US 7,116,448 B1Granted
Image forming apparatus, image forming system, printer controller, and computer-readable record medium
AssigneeMinolta Co., Ltd.
InventorYoko Fujiwara
Life of this patent
Estimating the term…
Abstract
An image forming system for suppressing the generation of moiré effect of a print image, provided with a receiving apparatus for receiving an image data of a document, a printer controller for detecting a screen angle of a document image based on the image data, selecting from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and setting the dither pattern, and a printer for reproducing a quasi-halftone using the dither pattern set up by the printer controller.
Claims24
An image forming apparatus comprising:
- a receiving unit receiving image data;
- a detecting unit detecting a screen angle of an image pattern described on a document based on the image data;
- a setup unit selecting from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and setting up the dither pattern;
- and
- a printing unit reproducing a quasi-halftone using the dither pattern set up by said setup unit, wherein said detecting unit detects screen angles of image data for cyan, magenta and yellow colors, and said setup unit selects from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and sets up the dither pattern for each color.
2 more elements
An image forming apparatus comprising:
- a receiving unit receiving image data;
- a detecting unit detecting a screen angle of an image pattern described on a document based on the image data;
- a setup unit selecting from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and setting up the dither pattern;
- and
- a printing unit reproducing a quasi-halftone using the dither pattern set up by said setup unit, wherein
- said detecting unit detects screen angles of image data for cyan, magenta and yellow colors, and said setup unit selects from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and sets up the dither pattern for each color, and
- said detection unit further comprises a color conversion unit converting the image data into cyan, magenta, yellow and black image data, a resolution conversion unit converting the cyan, magenta, yellow and black image data into high resolution image data, and a storage unit storing the high resolution image data, wherein screen angles of image data for cyan, magenta and yellow color are detected based on the image data stored in said storage unit.
4 more elements
An image forming apparatus comprising:
- a receiving unit receiving image data;
- a detecting unit detecting a screen angle of an image pattern described on a document based on the image data;
- a setup unit selecting from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and setting up the dither pattern;
- and
- a printing unit reproducing a quasi-halftone using the dither pattern set up by said setup unit, wherein said detecting unit has a plurality of detection patterns to compare the image data with the detection patterns, counts the numbers of image patterns that match with the detection patterns, and determines an angle of a detection pattern that provides a maximum matching count as the screen angle of the image data.
2 more elements
An image forming apparatus comprising:
- a receiving unit receiving image data;
- a detecting unit detecting a screen angle of an image pattern described on a document based on the image data;
- a setup unit selecting from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and setting up the dither pattern;
- and
- a printing unit reproducing a quasi-halftone using the dither pattern set up by said setup unit, wherein said detecting unit extracts an attention pixel from the image data, calculates average densities of peripheral pixels located in a plurality of directions relative to a direction perpendicular to the attention pixel, determines an angle that produces a maximum average density, and elects the determined angle as the screen angle of the image data.
2 more elements
An image reading apparatus comprising:
- a reading unit reading an image data of a document;
- a detection unit detecting a screen angle of an image pattern described on a document based on the image data;
- and
- a setup unit selecting from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and setting up the dither pattern,
- wherein said detecting unit detects screen angles of document images for cyan, magenta and yellow colors, and said setup unit selects from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and sets up the dither pattern for each color.
2 more elements
An image reading apparatus comprising:
- a reading unit reading an image data of a document;
- a detection unit detecting a screen angle of an image pattern described on a document based on the image data;
- and
- a setup unit selecting from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and setting up the dither pattern, wherein said detecting unit has a plurality of detection patterns to compare the image data with the detection patterns, counts the numbers of image patterns that match with the detection patterns, and determine an angle of a detection pattern that provides a maximum matching count as the screen angle of the document image.
1 more element
An image reading apparatus comprising:
- a reading unit reading an image data of a document;
- a detection unit detecting a screen angle of an image pattern described on a document based on the image data;
- and
- a setup unit selecting from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and setting up the dither pattern, wherein said detecting unit extracts an attention pixel from the image data, calculates average densities of peripheral pixels located in a plurality of directions relative to a direction perpendicular to the attention pixel, determines an angle that produces a maximum average density, and elects the determined angle as the screen angle of the document image.
1 more element
A printer controller comprising:
- a detection unit detecting a screen angle of an image pattern described on a document based on the image data;
- a setup unit selecting from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and setting the dither pattern;
- and
- a data generating unit generating a print data in order to reproduce a quasi-halftone using the dither pattern set up by said setup unit, wherein said detecting unit detects screen angles of image data for cyan, magenta and yellow colors, and said setup unit selects from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and sets up the dither pattern for each color.
1 more element
A printer controller comprising:
- a detection unit detecting a screen angle of an image pattern described on a document based on the image data;
- a setup unit selecting from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and setting the dither pattern;
- and
- a data generating unit generating a print data in order to reproduce a quasi-halftone using the dither pattern set up by said setup unit, wherein
- said detecting unit detects screen angles of image data for cyan, magenta and yellow colors, and said setup unit selects from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and sets up the dither pattern for each color, and
- said detection unit further comprises a color conversion unit converting the image data into cyan, magenta, yellow and black image data, a resolution conversion unit converting the cyan, magenta, yellow and black image data into high resolution image data, and a storage unit storing the high resolution image data, wherein screen angles of the image data for cyan, magenta and yellow color are detected based on the image data stored in said storage unit.
3 more elements
A printer controller comprising:
- a detection unit detecting a screen angle of an image pattern described on a document based on the image data;
- a setup unit selecting from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and setting the dither pattern;
- and
- a data generating unit generating a print data in order to reproduce a quasi-halftone using the dither pattern set up by said setup unit, wherein
- said detecting unit detects screen angles of image data for cyan, magenta and yellow colors, and said setup unit selects from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and sets up the dither pattern for each color, and
- said detecting unit has a plurality of detection patterns to compare the image data with the detection patterns, counts the numbers of image patterns that match with the detection patterns, and determines an angle of a detection pattern that provides a maximum matching count as the screen angle of the image data.
3 more elements
A printer controller comprising:
- a detection unit detecting a screen angle of an image pattern described on a document based on the image data;
- a setup unit selecting from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and setting the dither pattern;
- and
- a data generating unit generating a print data in order to reproduce a quasi-halftone using the dither pattern set up by said setup unit, wherein
- said detecting unit detects screen angles of image data for cyan, magenta and yellow colors, and said setup unit selects from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and sets up the dither pattern for each color, and
- said detecting unit extracts an attention pixel from the image data, calculates average densities of peripheral pixels located in a plurality of directions relative to a direction perpendicular to the attention pixel, determines an angle that produces a maximum average density, and elects the determined angle as the screen angle of the image data.
3 more elements
An image forming system comprising:
- a receiving apparatus for receiving image data;
- a printer controller for detecting a screen angle of an image pattern described on a document based on the image data, selecting from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and setting the dither pattern;
- and
- a printer for reproducing a quasi-halftone using the dither pattern set up by said printer controller, wherein
- said printer controller detects screen angles of image data for cyan, magenta and yellow colors, and selects from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and sets up the dither pattern for each color.
2 more elements
An image forming system comprising:
- a receiving apparatus for receiving image data;
- a printer controller for detecting a screen angle of an image pattern described on a document based on the image data, selecting from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and setting the dither pattern;
- and
- a printer for reproducing a quasi-halftone using the dither pattern set up by said printer controller, wherein
- said printer controller has a plurality of detection patterns to compare the image data with the detection patterns, counts the numbers of image patterns that match with the detection patterns, and determines an angle of a detection pattern that provides a maximum matching count as the screen angle of the image data.
2 more elements
An image forming system comprising:
- a receiving apparatus for receiving image data;
- a printer controller for detecting a screen angle of an image pattern described on a document based on the image data, selecting from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and setting the dither pattern;
- and
- a printer for reproducing a quasi-halftone using the dither pattern set up by said printer controller, wherein
- said printer controller extracts an attention pixel from the image data, calculates average densities of peripheral pixels located in a plurality of directions relative to a direction perpendicular to the attention pixel, determines an angle that produces a maximum average density, and elects the determined angle as the screen angle of the image data.
2 more elements
A computer-readable medium for storing a program readable and executable by a computer, said program performing the steps of:
- (A) receiving image data;
- (B) detecting a screen angle of an image pattern described on a document based on the image data;
- (C) selecting from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and setting the dither pattern;
- and
- (D) reproducing a quasi-halftone using the setup dither pattern, wherein
- said step (B) of said program performs the steps of (1) converting the image data into cyan magenta, yellow and black image data, (2) converting said cyan, magenta, yellow and black image data into high resolution image data, (3) storing the high resolution image data, and (4) detecting screen angles of image data for cyan, magenta, and yellow colors based on the stored image data.
3 more elements
An image processing apparatus comprising:
- a receiving unit receiving image data;
- a detecting unit detecting a screen angle of an image pattern described on a document based on the image data;
- and
- a setup unit selecting, from a plurality of dither patterns, a dither pattern with a screen angle different from the detected screen angle and setting up the dither pattern, wherein said detecting unit detects screen angles of image data for cyan, magenta and yellow colors, and said setup unit selects from a plurality of dither patterns a dither pattern with a screen angle different from the detected screen angle and sets up the dither pattern for each color.
1 more element
Dependencies are inferred from the claim text.