Image processing apparatus, image processing method, image processing program, and storage medium

• US 8,441,701 B2
• Filed: 02/14/2012
• Issued: 05/14/2013
• Est. Priority Date: 07/07/2006
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Goto, Fumitaka, Suwa, Tetsuya, Goto, Fumihiro, Hashii, Yusuke, Kato, Masao, Yano, Kentaro
• Primary Examiner(s): ZHU, RICHARD Z
• Application Number:
  US13/396,364
• Publication Number:
  US 20120147432A1
• Time in Patent Office: 455 Days
• Field of Search: 358/1.9, 358/3.26, 358/3.27, 382254-269
• US Class Current: 358/532
• CPC Class Codes: G06K 15/02 using printers

Abstract

An image processing apparatus includes an obtaining unit, a determination unit, a setting unit, and a processing unit to perform an image edge intensifying processing. The obtaining unit obtains image data by reading a document. The determination unit determines an image edge direction. The setting unit sets an edge intensifying processing intensity based on the image data and a processing intensity determined corresponding to a difference between resolution in a main scanning direction and resolution in a sub-scanning direction. The processing unit performs the image edge intensifying processing according to the set intensity. In response to the resolution of the image data being higher in the sub-scanning direction than in the main scanning direction, the setting unit sets a higher intensity of the edge intensifying processing in response to the edge direction being along the sub-scanning direction than in response to the edge direction being along the main scanning direction.

Claims

1. An image processing apparatus for performing an edge intensifying processing of an image, the image processing apparatus comprising:

an obtaining unit configured to obtain image data generated by optically reading a document, the image data corresponding to respective pixels aligned in a main scanning direction and a sub-scanning direction perpendicular to the main scanning direction;

a determination unit configured to determine an edge direction of an image;

a setting unit configured to set an intensity of the edge intensifying processing based on the image data and an intensity of processing determined corresponding to a difference between resolution in the main scanning direction and resolution in the sub-scanning direction; and

a processing unit configured to perform the edge intensifying processing of an image according to the intensity set by the setting unit,

wherein, in response to the resolution of the image data being higher in the sub-scanning direction than in the main scanning direction, the setting unit sets a higher intensity of the edge intensifying processing in response to the edge direction being along the sub-scanning direction than in response to the edge direction being along the main scanning direction,

wherein the setting unit sets the intensity of processing according to a result of comparing a variation amount of the image data in the edge direction with a threshold, and

wherein the setting unit sets the threshold such that the intensity of the edge intensifying processing varies according to the variation amount in an alignment direction of pixels.

2. The image processing apparatus according to claim 1, further comprising:

a sensor configured to read a document image, the sensor having imaging elements aligned in the main scanning direction at an interval corresponding to predetermined resolution,

wherein the image data is obtained by reading the document at first resolution equal to or lower than the predetermined resolution in the main scanning direction and reading the document at second resolution higher than the first resolution in the sub-scanning direction, while moving the sensor in the sub-scanning direction.

3. The image processing apparatus according to claim 1, wherein the threshold includes a first threshold equal to or lower than a variation amount of pixels in the sub-scanning direction and a second threshold equal to or higher than a variation amount of pixels in the main scanning direction.

4. The image processing apparatus according to claim 1, wherein the edge intensifying processing is at least one of replacement processing, filter processing, and achromatic coloring processing.

5. The image processing apparatus according to claim 4, wherein correction intensity is replacement intensity.

6. The image processing apparatus according to claim 4, wherein correction intensity is filter intensity.

7. The image processing apparatus according to claim 4, wherein correction intensity is achromatic coloring intensity.

8. An image processing method for performing an edge intensifying processing of an image, the image processing method comprising:

obtaining image data generated by optically reading a document, the image data corresponding to respective pixels aligned in a main scanning direction and a sub-scanning direction perpendicular to the main scanning direction;

determining an edge direction of an image;

setting an intensity of the edge intensifying processing based on the image data and an intensity of processing determined corresponding to a difference between resolution in the main scanning direction and resolution in the sub-scanning direction; and

performing the edge intensifying processing of an image according to the set intensity,

wherein, in response to the resolution of the image data being higher in the sub-scanning direction than in the main scanning direction, setting includes setting a higher intensity of the edge intensifying processing in response to the edge direction being along the sub-scanning direction than in response to the edge direction being along the main scanning direction,

wherein setting includes setting the intensity of processing according to a result of comparing a variation amount of the image data in the edge direction with a threshold, and

wherein setting includes setting the threshold such that the intensity of the edge intensifying processing varies according to the variation amount in an alignment direction of pixels.