JPH09330398A - Color information converting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the retrieval and output of image information containing color information out of a distributed data base system even from facsimile equipment by successively converting the color information of respective picture elements in the image information to monochromatic image information having luminance information preserving the distance relation among the respective pieces of color information inside a color space. SOLUTION: The color information of respective picture elements in the image information is successively inputted from an image information input means 1. A coordinate transforming means 2 transforms the inputted color information to a discrete coordinate system having coordinate axes expressing luminance components and stores the coordinate values of transformed color information in a color coordinate information storage means 31. On the other hand, a Peano scan processing means 32 scans all the grid points of the discrete coordinate system along a three-dimensional Peano curve with the origin of the discrete coordinate system as a starting point to an ending point on the coordinate axes expressing the luminance components and outputs the information of distance from the starting point to the ending point at the time when the coordinate values of grid points are coincident with the coordinate axes stored in the color coordinate information storage means 31. A luminance value converting means 4 performs arithmetic for multiplying the distance information for a constant and outputs the result to a luminance value output means 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color information conversion device, and in particular, it is effective when applied to a technique for outputting color image information including a plurality of color information to a facsimile device or the like capable of outputting only monochrome image information. The present invention relates to a color information conversion device.

[0002]

2. Description of the Related Art WWW constructed on the Internet
From a facsimile machine that can only input / output monochrome information in a distributed database system composed of an information storage device and an information search device connected via a network composed of telecommunications equipment such as (World Wide Web) When performing information retrieval and information output, it is necessary to convert the image information stored in the information storage device into monochrome image information, and further, the monochrome image information is facsimile-encoded and output to the facsimile device. At this time, if the image information includes color information, conventionally, only the luminance information of the color information is extracted and converted into monochrome image information.

[0003]

The present inventor has found the following problems as a result of examining the above-mentioned prior art.

In the above-mentioned prior art, the distance relationship in the color space of the color information in the image information could not be saved in the monochrome image information. Therefore, there is a problem that a plurality of pieces of color information that can be identified on the image information are difficult to identify or cannot be identified on the converted monochrome image information.

An object of the present invention is to realize an information conversion apparatus capable of retrieving and outputting image information including color information from a distributed database system even by a facsimile machine.

The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[0007]

The outline of a typical invention among the inventions disclosed in the present application will be briefly described as follows.

A color information conversion device for converting color image information including a plurality of color information into monochrome image information while preserving the distance relationship of each color information in the color space, and image information input means for inputting image information. And coordinate conversion means for converting color information of each pixel forming the image information into coordinate values of lattice points in a discrete coordinate system having a luminance component as an axis,
Peano scanning means for extracting distance information from the starting point to the grid point along a three-dimensional Peano curve having an origin of the discrete coordinate system as a starting point and an end point on the axis of the luminance component. A brightness value conversion means for extracting a brightness value from the distance information and a brightness value output means for outputting the brightness value.

With this configuration, the color information of the image information is converted into monochrome image information so as to preserve the distance relationship in the color space as much as possible, so that the image information including the color information is dispersed even from the facsimile apparatus. It is possible to realize an information conversion device capable of searching and outputting from a type database system.

According to the principle of the present invention, first, the original image information I is composed of M × N pixels, and the color information p (x, y) (x = 0, ..., M-1; y) of each pixel. = 0, ..., N-
It is assumed that 1) has Q types in the entire image information I. That is, p (x, y) = Ci (i = 0, ..., Q-1). Here, each color Ci is set to HVS (Hue Value S
animation) or YUV coordinates (HVS, YUV
The coordinate is a coordinate system that represents color) and the like is converted to a coordinate system that includes a luminance component in the base. This coordinate system is a discrete coordinate system and forms grid points of m × m × m, and the coordinate values of each color information after conversion are normalized and quantized to the nearest neighboring grid points of the discrete coordinate system. It Let each color after this conversion be C'i.

Next, the discrete coordinate system is scanned by a three-dimensional Peano curve. Peano (P
As shown in FIG. 2, the eano) curve is a fractal figure and has a very complicated shape that is not random, and it is a one-dimensional curve with the adjacency of each lattice point in the n-dimensional space preserved to some extent. Can be mapped on.
Therefore, the start point is the origin of the HVS or YUV coordinates, the end point is on the luminance axis (that is, the V axis or the Y axis), and m ×
Three-dimensional Peano (Pean) passing through all m × m lattice points
o) Generate a curve. And, the Peano
o) By scanning the color C'i along the curve, the point C i, which is a mapping of the color C'i on the Peano curve, is obtained.

A value vi = αL proportional to the distance Li from the origin to each color Pi along the Peano curve.
Let i be the brightness value after conversion to a monochrome image. Like this
By converting the color information Ci of the image information into the brightness value vi, the Peano curve starts from the origin of the coordinate system and ends on the brightness axis. Therefore, the distance of each color Ci in the color space The relationship can be saved to some extent after conversion to vi.

Therefore, it is possible to solve the problem that a plurality of color information that can be identified on the original image information becomes difficult or indistinguishable on the converted monochrome image information. Become. A facsimile machine or the like can only output black and white binary, but it is possible to output monochrome image information by converting the brightness value vi into a dither method or an error diffusion method.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments (examples) of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing a schematic structure of a color information conversion apparatus according to an embodiment of the present invention. 1 is image information input means, 2 is coordinate conversion means, and 3 is Peano.
Scanning means, 31 is color coordinate information accumulating means, 32 is Peano scanning processing means, 4 is brightness value converting means, 5
Is a brightness value output means.

As shown in FIG. 1, the color information conversion apparatus of this embodiment has an image information input unit 1, a coordinate conversion unit 2, a Peano scanning unit 3, a brightness value conversion unit 4, and a brightness value output unit. It is composed of 5. The Peano (P
The eano scanning unit 3 includes a color coordinate information storage unit 31 and a Peano scanning processing unit 32.

Next, the operation of the color information conversion apparatus of this embodiment will be described. In FIG. 1, first, the image information inputting means 1 sequentially inputs the color information of each pixel composed of RGB values and the like forming the image information. Coordinate conversion means 2
Converts the color information input from the image information input unit 1 into a discrete coordinate system having coordinate axes representing a luminance component such as HVS or YUV, and converts the coordinate value of the converted color information into the color coordinate information storage unit 31. Accumulate in.

The Peano scanning processing means 3
2 scans all the lattice points of the discrete coordinate system along a three-dimensional Peano curve having the origin of the discrete coordinate system as the starting point and the coordinate axis representing the luminance component as the end point,
The three-dimensional Peano (Pe) when the coordinate value of the grid point matches the coordinate value stored in the color coordinate information storage means 31.
ano) Output distance information from the start point along the curve to the grid point. The brightness value conversion means 4 carries out an operation for multiplying the distance information by a constant, and as brightness information, the brightness value output means 5
Output to

With such a configuration, the color information of each pixel of the image information input from the image information inputting means 1 is sequentially stored as the luminance information in which the distance relationship between the color information in the color space is stored. It is possible to convert it into the monochrome image information that it has.

As described above, the invention made by the present inventor is
Although the present invention has been specifically described based on the above-mentioned embodiments, the present invention is not limited to the above-mentioned embodiments, and it goes without saying that various modifications can be made without departing from the scope of the invention.

[0021]

The effects obtained by typical aspects of the invention disclosed in the present application will be briefly described as follows.

Color information of each pixel of the input image information is
The color information is sequentially converted into monochrome image information having brightness information that preserves the distance relationship in the color space, so when converting color image information to monochrome image information, it can be identified on the original color image information. Multiple color information
It is possible to identify even on the converted monochrome image information.

As a result, it is possible to realize an information conversion apparatus that enables a facsimile apparatus to retrieve and output image information including color information from a distributed database system.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a color information conversion device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a Peano curve.

[Explanation of symbols]

1 ... Image information input means, 2 ... Coordinate conversion means, 3 ... Peano scanning means, 31 ... Color coordinate information storage means,
32 ... Peano scanning processing means, 4 ... Luminance value conversion means, 5 ... Luminance value output means.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Noboru Sonehara 3-19-2 Nishishinjuku, Shinjuku-ku, Tokyo Nippon Telegraph and Telephone Corporation

Claims (1)

[Claims] 1. Color image information including a plurality of color information,
A color information conversion device for converting into color image information while maintaining the distance relationship in the color space of each color information,
Image information input means for inputting image information, coordinate conversion means for converting color information of each pixel forming the image information into coordinate values of lattice points in a discrete coordinate system having a luminance component as an axis, and the discrete coordinate system. And a distance information from the starting point to the grid point along a three-dimensional Peano curve whose origin is the origin and whose end point is on the axis of the luminance component. A color information conversion device comprising: a brightness value conversion means for extracting a brightness value from the brightness value and a brightness value output means for outputting the brightness value.