Method for improving hybrid halftoning and apparatus therefor

• US 10,482,360 B2
• Filed: 12/08/2015
• Issued: 11/19/2019
• Est. Priority Date: 02/17/2015
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Jang, Seul-ki, Yi, Ji-young
• Primary Examiner(s): Vo, Quang N
• Application Number:
  US15/551,825
• Publication Number:
  US 20180039871A1
• Time in Patent Office: 1,442 Days
• Field of Search: 358 306, 358 19, 358 115
• CPC Class Codes: G06F 3/1208 resulting in improved quality of the output result, e.g. print layout, colours, workflows, print preview
• CPC Class Codes: G06F 3/1247 by conversion to printer ready format
• CPC Class Codes: G06K 15/1881 Halftoning halftoning of still images in general H04N1/405, H04N1/52
• CPC Class Codes: G06K 2215/0094 Colour printing
• CPC Class Codes: G06V 10/44 Local feature extraction by analysis of parts of the pattern, e.g. by detecting edges, contours, loops, corners, strokes or intersections; Connectivity analysis, e.g. of connected components
• CPC Class Codes: G06V 30/10 Character recognition
• CPC Class Codes: G06V 30/18105 related to colour
• CPC Class Codes: H04N 1/4052 by error diffusion, i.e. transferring the binarising error to neighbouring dot decisions
• CPC Class Codes: H04N 1/4092 Edge or detail enhancement
• CPC Class Codes: H04N 1/52 Circuits or arrangements for halftone screening
• CPC Class Codes: H04N 1/58 Edge or detail enhancement; Noise or error suppression, e.g. colour misregistration correction H04N1/62 takes precedence

Abstract

Provided is a method by which an image forming apparatus forms an image, the method including detecting a boundary area in a portion of image data; determining a direction of the boundary area, a dominant color of the boundary area, and an edge intensity of the boundary area; determining enhancement information with respect to the boundary area based on the direction, the dominant color, and the edge intensity; and forming an image with respect to the image data based on the determined enhancement information.

Claims

1. A method by which an image forming apparatus forms an image, the method comprising:

detecting a boundary area in a portion of image data;

determining a direction of the boundary area, a dominant color of the boundary area, and an edge intensity of the boundary area;

determining enhancement information with respect to the boundary area based on the direction, the dominant color, and the edge intensity; and

forming an image with respect to the image data based on the determined enhancement information,

wherein error diffusion is applied to an area where text is displayed, and dithering is applied to an area where a background of the text is displayed.

2. The method of claim 1, wherein the boundary area is a boundary area between two areas to which different half-toning methods are applied.

3. The method of claim 1, wherein the direction of the boundary area is information expressible as a 2-dimensional vector in the portion of the image data.

4. The method of claim 1, wherein the dominant color of the boundary area is determined from information about one or more colors of the boundary area based on a pre-set equation.

5. The method of claim 1, wherein the edge intensity of the boundary area varies according to concentrations of the one or more colors of the boundary area.

6. The method of claim 1, wherein the boundary area is a boundary area between an error diffusion area and a screening area.

7. The method of claim 6, wherein the error diffusion area is an area for expressing detail information, and

the screening area is an area for expressing information other than the detail information.

8. The method of claim 1, wherein the enhancement information with respect to the boundary area comprises at least one selected from the group of a color and a concentration of a line formed in the boundary area.

9. An image forming apparatus comprising:

a network interface that receives data related to a user format document from outside;

a memory that stores data regarding the received user format document;

a control unit; and

a printing module that prints the user format document based on determined enhancement information,

wherein the control unit is configured to detect a boundary area in a portion of image data, determine a direction of the boundary area, a dominant color of the boundary area, and an edge intensity of the boundary area, and determine enhancement information with respect to the boundary area based on the direction, the dominant color, and the edge intensity, and

wherein error diffusion is applied to an area where text is displayed, and dithering is applied to an area where a background of the text is displayed.

10. The image forming apparatus of claim 9, wherein the boundary area is a boundary area between two areas to which different half-toning methods are applied.

11. The image forming apparatus of claim 9, wherein the direction of the boundary area is information expressible as a 2-dimensional vector in the portion of the image data.

12. The image forming apparatus of claim 9, wherein the dominant color of the boundary area is determined from information about one or more colors of the boundary area based on a pre-set equation.

13. The image forming apparatus of claim 9, wherein the edge intensity of the boundary area varies according to concentrations of the one or more colors of the boundary area.

14. The image forming apparatus of claim 9, wherein the boundary area is a boundary area between an error diffusion area and a screening area.

15. The image forming apparatus of claim 9, wherein the enhancement information with respect to the boundary area comprises at least one selected from the group of a color and a concentration of a line formed in the boundary area.