JPH10215368A - Image processing unit and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To synthesize a binary image having transparency. SOLUTION: A transparency mask generating circuit 10 generates a transparency mask pattern according to a transparency α denoted by an inputted transparency signal. A transparent processing circuit 12 ANDs between an inputted image A and the transparency mask pattern for every pixels, an opaque processing circuit 14 ANDs between an inputted image B and an input turning the transparency mask pattern for every pixels. An image synthesis circuit 16 ORs an output of the transparency processing circuit 12 and an output of the opaque processing circuit 14 to output the ORed signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an image processing apparatus and method for superimposing and combining two binary images.

[0002]

2. Description of the Related Art Conventionally, as a method of generating one binary image by superimposing two binary images, there is a method of obtaining a logical product (AND) between pixels, and other methods include various logical operations (knots). , OR and exclusive OR) are also known to provide special effects.

[0003]

However, in the conventional example,
There is a drawback that the composition ratio of two images cannot be specified. Therefore, it has been impossible to smoothly combine a binary image expressed in pseudo halftone.

An object of the present invention is to provide an image processing apparatus and method capable of solving such a problem and synthesizing a binary image with transparency.

[0005]

An image processing apparatus according to the present invention comprises a transparency mask generating means for generating a mask pattern corresponding to a specified transparency, and a first input image made transparent by the mask pattern. Transparent processing means, opacity processing means for opaque the second input image by the mask pattern, and image synthesizing means for synthesizing the output of the transparent processing means and the output of the opacity processing means. It is characterized by having.

[0006] An image processing method according to the present invention includes a transparency mask generating step of generating a mask pattern corresponding to a designated transparency, and a first step of generating a first mask by the mask pattern.
, An opacity processing step for opacity of the second input image by the mask pattern, and a result of the opacity processing step and a result of the opacity processing step are combined. And an image synthesizing step.

[0007] The transparency processing means or step acts to turn on a pixel having a ratio designated by the transparency among the ON pixels of the first input image, and the opacity processing means or step provides the second input image. It works to turn off the pixels of the ratio specified by the transparency among the ON pixels of the image. The composite result of the output of the transparency processing means or step and the output of the opacity processing means or step becomes a composite image having a ratio according to the transparency. That is, a binary image can be synthesized with transparency.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic block diagram of an embodiment of the present invention. In FIG. 1, reference numeral 10 denotes a transparency mask generation circuit that generates a transparency mask pattern (transparency mask) according to a transparency signal indicating transparency α, and 12 denotes a transparency mask output by the transparency mask generation circuit 10.
A transparency processing circuit for making the first input image A transparent by a pattern; Is an image synthesizing circuit for synthesizing the output of the transparency processing circuit 12 and the output of the opacity processing circuit 14.

The operation of the embodiment will be described. The transparency mask generation circuit 10 generates a transparency mask pattern according to the transparency α indicated by the input transparency signal. Note that the transparency α takes a value in the range of 0 to 1, and 0 is a completely opaque state (the underlying image is not completely visible) and 1 is a completely transparent (the underlying image is all visible) state. Shall be expressed. FIG. 2 is an example of a threshold value for determining ON / OFF of a mask pattern. Transparency mask generation circuit 10
Generates a transparency mask pattern in which pixels at positions where the threshold value is equal to or greater than α / 64 are turned on. FIG. 3 shows an example of the generated transparency mask pattern. FIG.
(1), (2) and (3) indicate the transparency α
= 0.25, 0.5 and 0.75 transparency mask patterns. Black pixel portions are completely opaque (opaque pixels), and white pixel portions are completely transparent (transparent pixels).

The transparency processing circuit 12 performs a logical product (AND) for each pixel between the input image A and the transparency mask pattern output from the transparency mask generation circuit 10.
Here, since the transparency mask pattern is assumed to be composed of a total of 16 pixels, that is, 8 pixels vertically and horizontally, it is applied by repeating every 8 pixels. Thereby, among the ON pixels of the input image A,
Pixels corresponding to the transparent pixels of the transparency mask pattern are turned on. FIG. 4 shows an example of the input image A processed by the transparency processing circuit 12. 4A shows an input image A, FIG. 4B shows a result obtained by repeating the transparency mask pattern so as to have the same size as the input image A, and FIG.

The opacity processing circuit 14 includes an input image B and a transparency mask output from the transparency mask generation circuit 10.
The logical product (AND) is calculated for each pixel with the inverted pattern. As a result, among the ON pixels of the input image B, the pixels corresponding to the opaque pixels of the transparency mask pattern are turned OFF. FIG. 5 shows a processing example of the opacity processing circuit 14. FIG. 5A shows an input image B, FIG. 5B shows a result obtained by repeating an inverted transparency mask pattern so as to have the same size as the input image B, and FIG.

The image synthesizing circuit 16 includes a transparency processing circuit 12
OR of the output of the opaque processing circuit 14 with the output of the
Take and output. FIG. 6 shows a result obtained by combining the processing result of the transparency processing circuit 12 shown in FIG. 4C and the processing result of the opacity processing circuit 14 shown in FIG.

According to this embodiment, a binary image can be synthesized with transparency. The present invention is also applicable to the synthesis of a color binary image. For example, when synthesizing a color binary image composed of YMCK, the above-described processing may be performed on each component of YMCK.

It is needless to say that some or all of the functions of the present invention can be realized by software or hardware.

[0016]

As can be easily understood from the above description, according to the present invention, two binary images can be synthesized with desired transparency.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram of an embodiment of the present invention.

FIG. 2 is an example of a threshold value for generating a transparency mask pattern.

FIG. 3 is an example of a transparency mask pattern.

FIG. 4 is a processing example of a transparency processing circuit 12;

FIG. 5 is a processing example of an opacity processing circuit 14;

FIG. 6 is an example of an output image.

[Explanation of symbols]

 10: transparency mask generation circuit 12: transparency processing circuit 14: opacity processing circuit 16: image synthesis circuit

Claims (6)

[Claims] 1. A transparency mask generating means for generating a mask pattern corresponding to a designated transparency, a transparency processing means for making a first input image transparent by the mask pattern, and a transparency processing means by the mask pattern. 2. An image processing apparatus, comprising: an opacity processing means for opaque input image; and an image synthesizing means for synthesizing an output of the transparency processing means and an output of the opacity processing means. 2. The image processing apparatus according to claim 1, wherein said transparency mask generation means generates a mask pattern in which pixels of a ratio corresponding to the transparency are turned on. 3. The transparency processing means calculates a logical product for each pixel between the first input image and the mask pattern, and the opacity processing means performs a logical product operation on the second input image and the mask pattern. 3. The image processing apparatus according to claim 1, wherein a logical product is obtained for each pixel between the mask pattern and the inverted one. 4. A transparency mask generating step for generating a mask pattern corresponding to the designated transparency, a transparency processing step for rendering a first input image transparent by the mask pattern, and a transparency masking step by the mask pattern. 2. An image processing method, comprising: an opacity processing step of making an input image opaque; and an image synthesis step of synthesizing a result of the transparency processing step and a result of the opacity processing step. 5. The image processing method according to claim 4, wherein the transparency mask generating step generates a mask pattern in which pixels of a ratio corresponding to the transparency are turned on. 6. The transparency processing step performs a logical product operation on the pixel between the first input image and the mask pattern, and the opacity processing step performs the logical operation on the second input image and the mask pattern. 6. The image processing method according to claim 4, wherein a logical product is obtained for each pixel between the mask pattern and the inverted one.