Image processing apparatus, method, and medium

Patent metadata

Field	Value
Publication number	US-9773319-B2
Application number	US-201514720543-A
Country	US
Kind code	B2
Filing date	May 22, 2015
Priority date	May 26, 2014
Publication date	Sep 26, 2017
Grant date	Sep 26, 2017

Abstract

An image process to be performed on an edge of a character or a line is not performed on pixels included in a mosaic image.

First claim

What is claimed is:

1. An image processing apparatus comprising:
a memory storing instructions; and
one or more processors which execute instructions and cause the image processing apparatus to function as:
a first determination unit configured to determine whether a target pixel in an input image is a pixel of an edge portion;
a second determination unit configured to determine whether the target pixel is included in a mosaic image in accordance with pitches between rows and pitches between columns; and
a performing unit configured to enhance reproducibility of an edge to the target pixel in a case where the target pixel is determined to be the pixel of the edge portion and the target pixel is not included in the mosaic image, and not enhance reproducibility of an edge to a target pixel in a case where the target pixel is determined to be a pixel of the edge portion and the target pixel is included in the mosaic image.

2. The image processing apparatus according to claim 1 , wherein
black monochromatization is performed on the target pixel when the target pixel has an achromatic color.

3. The image processing apparatus according to claim 1 , wherein the second determination unit comprises:
a counting unit configured to count a number of edges in a horizontal direction and a number of edges in a vertical direction included in a window including the target pixel;
a flagging unit configured to set flags in rows and columns having counting results larger than a threshold value; and
a determination unit configured to determine whether the target pixel is included in a mosaic region in accordance with pitches between the rows to which the flags are set and pitches between the columns to which the flags are set.

4. The image processing apparatus according to claim 3 , wherein the determination unit determines
in the determining, as the third determination, that is determined that the target pixel is included in a mosaic region when a minimum value of the pitches between the rows and a minimum value of the pitches between the columns are both two or more and a value obtained by subtracting the minimum value from a maximum value of the pitches between the rows and a value obtained by subtracting the minimum value from a maximum value of the pitches between the columns are both one or less.

5. An image processing method comprising:
determining whether a target pixel in an input image is pixel of an edge portion as a first determination;
determining whether the target pixel is included in a mosaic image in accordance with pitches between rows and pitches between columns as a second determination; and
enhancing reproducibility of an edge to the target pixel in a case where the target pixel is determined to the pixel of an edge portion and the target pixel is not included in the mosaic image; and
not enhancing reproducibility of an edge to a target pixel in a case where the target pixel is determined to be a pixel of the edge portion and the target pixel is included in the mosaic image.

6. The image processing method according to claim 5 , wherein
black monochromatization is performed on the target pixel in the image process when the target pixel has an achromatic color.

7. The image processing method according to claim 5 , wherein
the second determination comprises:
counting a number of edges in a horizontal direction and a number of edges in a vertical direction included in a window including the target pixel;
setting flags in rows and columns having counting results larger than a threshold value; and
determining, as a third determination, whether the target pixel is included in a mosaic region in accordance with a pitch between the rows to which the flags are set and pitch between the columns to which the flags are set.

8. The image processing method according to claim 7 , wherein
in the determining, as the third determination, it is determined that the target pixel is included in a mosaic region when a minimum value of the pitches between the rows and a minimum value of the pitches between the columns are both two or more and a value obtained by subtracting the minimum value from a maximum value of the pitches between the rows and a value obtained by subtracting the minimum value from a maximum value of the pitches between the columns are both one or less.

9. A non-transitory computer-readable recording medium storing a program that causes a computer to function as each of the units of an image processing apparatus comprising:
a first determination unit configured to determine whether a target pixel in an input image is pixel of an edge portion as a first determination;
a second determination unit configured to determine whether the target pixel is included in a mosaic image as a second determination in accordance with pitches between rows and pitches between columns; and
a performing unit configured to enhance reproducibility of an edge to the target pixel in a case where the target pixel is determined to be the pixel of the edge portion and the target pixel is not includes in the mosaic image, and not enhance reproducibility of an edge to a target pixel in a case where the target pixel is determined to be a pixel of the edge portion and the target pixel is included in the mosaic image.

Assignees

• Canon Kk

Inventors

• Oka Hiroyuki

Classifications

• G06T11/10

  Texturing; Colouring; Generation of textures or colours (retouching, inpainting or scratch removal G06T5/77) · CPC title

• H04N1/56

  Processing of colour picture signals (H04N1/52 takes precedence) · CPC title

• G06T11/00

  Two-dimensional [2D] image generation · CPC title

• G06T7/13 Primary

  Edge detection · CPC title

• G06T11/001

  Physics · mapped topic