Method and apparatus for half toning image

• US 20050243376A1
• Filed: 02/01/2005
• Published: 11/03/2005
• Est. Priority Date: 05/01/2004
• Status: Abandoned Application

• Current Assignee: S-Printing Solution Co., Ltd. (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Sang-ho
• Application Number:
  US11/046,683
• Publication Number:
  US 20050243376A1
• Time in Patent Office: Days
• US Class Current: 358/3.30
• CPC Class Codes: H04N 1/4052 by error diffusion, i.e. transferring the binarising error to neighbouring dot decisions

Abstract

A method and apparatus for half-toning an image is provided having operations for transforming a gray scale image into a binary image, enhancing a resolution of the binary image using a resolution enhancement technology, and diffusing an error between the gray scale image and a resolution-enhanced binary image. Thus, resolution enhancement technology (RET) is accounted for in an image half-toning algorithm so that image forming apparatuses (for example, a printer or a multi-function machine), or displays to which the RET is applied, can output an image of optimal quality.

Claims

1. An image half toning method comprising the steps of:

transforming a gray scale image into a binary image;

enhancing a resolution of the binary image using a resolution enhancement technology; and

diffusing an error between the gray scale image and a resolution-enhanced binary image.

2. The image half toning method of claim 1, further comprising the step of:

correcting the resolution-enhanced binary image to have a brightness value of a real image output by an image forming apparatus prior to the step of diffusing the error between the gray scale image and a resolution-enhanced binary image.

3. An image half toning method comprising the steps of:

transforming a gray scale image into a binary image;

enhancing a resolution of the binary image using a resolution enhancement technology;

filtering the resolution-enhanced binary image using a first visual filter; and

calculating a difference between a first filtering value of the binary image filtered by the first visual filter and a second filtering value of the gray scale image filtered by a second visual filter.

4. The image half toning method of claim 3, wherein the first and second visual filter are configured to correspond to a sense of human eyesight.

5. The image half toning method of claim 3, further comprising the step of:

correcting the resolution-enhanced binary image to have a brightness value of a real image output by an image forming apparatus prior to the step of filtering the resolution-enhanced binary image.

6. An image half toning apparatus comprising:

a threshold value comparator for transforming a gray scale image into a binary image;

a resolution enhancer for enhancing a resolution of the binary image; and

an error diffuser for diffusing an error between the gray scale image and a resolution-enhanced binary image.

7. The image half toning apparatus of claim 6, further comprising a brightness value corrector for correcting the resolution-enhanced binary image to have a brightness value of a real image output by an image forming apparatus.

8. An image half toning apparatus comprising:

a threshold value comparator for transforming a gray scale image into a binary image;

a resolution enhancer for enhancing a resolution of the binary image;

a plurality of visual filters for performing filtering corresponding to a sense of human eyesight; and

a filtering value calculator for calculating a difference between a first filtering value of the binary image filtered by one of the visual filters and a second filtering value of the gray scale image filtered by another visual filter.

9. The image half toning apparatus of claim 8, further comprising a brightness value corrector for correcting the resolution-enhanced binary image to have a brightness value of a real image output by an image forming apparatus.