Image processing apparatus, image forming apparatus, printer driver, image processing method and computer-readable storage medium

• US 20050200905A1
• Filed: 06/12/2003
• Published: 09/15/2005
• Est. Priority Date: 06/19/2002
• Status: Active Grant

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Kimura, Takashi
• Granted Patent: US 7,576,886 B2
• Time in Patent Office: Days
• US Class Current: 358/3.270
• CPC Class Codes: B41J 2/21 for multi-colour printing
• CPC Class Codes: B41J 2002/14411 Groove in the nozzle plate
• CPC Class Codes: G06K 15/02 using printers
• CPC Class Codes: G06K 15/102 using ink jet print heads
• CPC Class Codes: G06K 2215/006 Anti-aliasing raster data

Abstract

An image forming apparatus forms an image by a plurality of dots, by forming a periphery of a stepped transition portion of a contour portion of at least a character and/or graphics of the image by dots having a smaller size than dots forming portions other than the stepped transition portion, and determining a method of forming the dots having the smaller size depending on an inclination of the contour portion.

Claims

1. An image forming apparatus for forming an image by a plurality of dots, comprising:

forming means for forming a periphery of a stepped transition portion of a contour portion of at least a character and/or graphics of the image by dots having a smaller size than dots forming portions other than the stepped transition portion; and

determining means for determining a method of forming the dots having the smaller size depending on an inclination of the contour portion.

2. The image forming apparatus as claimed in claim 1, wherein said determining means determines the smaller size of the dots depending on the inclination of the contour line portion.

3. The image forming apparatus as claimed in claim 1 or 2, wherein said determining means varies a number of dots having the smaller size depending on the inclination of the contour portion.

4. The image forming apparatus as claimed in any of claims 1 to 3, wherein said forming means forms the periphery of the stepped transition portion by the dots having the smaller size than the dots forming the portions other than the stepped transition portion when a resolution is low.

5. The image forming apparatus as claimed in any of claims 1 to 4, wherein said forming means includes detection means for detecting the stepped transition portion of the image, and said determining means includes dot data conversion means for converting the dots in the periphery of the stepped transition portion into the dots having the smaller size than the dots forming the portions other than the stepped transition portion.

6. The image forming apparatus as claimed in any of claims 1 to 5, wherein said forming means includes a head which ejects an ink onto a recording medium and forms the dots by drops of the ink to form the image on the recording medium.

7. The image forming apparatus as claimed in claim 6, wherein said ink includes a pigment, a soluble organic solvent, anion or nonion based surface active agent, polyole or glycol ether with carbon number 8 or greater, and pure water.

8. An image processing apparatus for forming an image data which is used to form a corresponding image by a plurality of dots, comprising:

converting means for converting a periphery of a stepped transition portion of a contour portion of at least a character and/or graphics of the image into dots having a smaller size than dots forming portions other than the stepped transition portion; and

determining means for determining a method of converting the dots having the smaller size depending on an inclination of the contour portion.

9. The image processing apparatus as claimed in claim 8, wherein said determining means determines the smaller size of the dots depending on the inclination of the contour line portion.

10. The image processing apparatus as claimed in claim 8 or 9, wherein said determining means varies a number of dots having the smaller size depending on the inclination of the contour portion.

11. The image processing apparatus as claimed in any of claims 8 to 10, wherein said converting means converts the dots at the periphery of the stepped transition portion into the dots having the smaller size when a low-resolution recording is selected.

12. A printer driver for creating an image data to be supplied to an image forming apparatus which forms a corresponding image by a plurality of dots, comprising:

converting means for converting a periphery of a stepped transition portion of a contour portion of at least a character and/or graphics of the image into dots having a smaller size than dots forming portions other than the stepped transition portion; and

determining means for determining a method of converting the dots having the smaller size depending on an inclination of the contour portion.

13. The printer driver as claimed in claim 12, wherein said determining means determines the smaller size of the dots depending on the inclination of the contour line portion.

14. The printer driver as claimed in claim 12 or 13, wherein said determining means varies a number of dots having the smaller size depending on the inclination of the contour portion.

15. The printer driver as claimed in any of claims 12 to 14, wherein said converting means converts the dots at the periphery of the stepped transition portion into the dots having the smaller size when a low-resolution recording is selected.

16. The printer driver as claimed in any of claims 12 to 15, wherein the image forming apparatus includes a head which ejects an ink onto a recording medium and forms the dots by drops of the ink to form the image on the recording medium, and said ink includes a pigment, a soluble organic solvent, anion or nonion based surface active agent, polyole or glycol ether with carbon number 8 or greater, and pure water.

17. An image processing method for forming an image data which is used to form a corresponding image by a plurality of dots, comprising:

converting a periphery of a stepped transition portion of a contour portion of at least a character and/or graphics of the image into dots having a smaller size than dots forming portions other than the stepped transition portion; and

determining a method of converting the dots having the smaller size depending on an inclination of the contour portion.

18. The image processing method as claimed in claim 17, wherein the smaller size of the dots is determined depending on the inclination of the contour line portion.

19. The image processing method as claimed in claim 17 or 18, wherein a number of dots having the smaller size is varied depending on the inclination of the contour portion.

20. The image processing method as claimed in any of claims 17 to 19, wherein the dots at the periphery of the stepped transition portion are converted into the dots having the smaller size when a low-resolution recording is selected.

21. A computer-readable storage medium which stores a program for causing a computer to form an image data which is used to form a corresponding image by a plurality of dots, said program comprising:

a converting procedure which causes the computer to convert a periphery of a stepped transition portion of a contour portion of at least a character and/or graphics of the image into dots having a smaller size than dots forming portions other than the stepped transition portion; and

a determining procedure which causes the computer to determine a method of converting the dots having the smaller size depending on an inclination of the contour portion.

22. The computer-readable storage medium as claimed in claim 21, wherein said determining procedure causes the computer to determine the smaller size of the dots depending on the inclination of the contour line portion.

23. The computer-readable storage medium as claimed in claim 21 or 22, wherein said determining procedure causes the computer to vary a number of dots having the smaller size depending on the inclination of the contour portion.

24. The computer-readable storage medium as claimed in any of claims 21 to 23, wherein said converting procedure causes the computer to convert the dots at the periphery of the stepped transition portion into the dots having the smaller size when a low-resolution recording is selected.