JP2674100B2 - Color image converter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention calculates a psychological image of a color image, displays the image in a psychological display language to an operator, and responds to a psychological image conversion request from the operator. The present invention relates to an apparatus for performing color conversion.

(Prior art) One of the methods of expressing colors within a range that can be seen by human eyes is as follows.
A Munsell color system expressed by three attributes of lightness (V), saturation (C), and hue (H) is known. Although this color system is a physical scale, you can objectively grasp the color,
It had nothing to do with the psychological image people perceive in color.

Therefore, a colorimetric method called a color image scale has been proposed as a method for expressing a psychological image of color (Japanese Patent Publication No. 56-46082). This color image scale psychologically analyzes the unique image of each color, arranges the colors using the degree of the image as a scale, and assigns colors to the psychological coordinate system as shown in FIGS. 6 and 7. A psychological display language is arranged, and by using this, it is possible to associate colors with a psychological language and perform equivalent conversion between them.

However, a specific device for displaying the entire color image in one psychological display language or converting the image into an image specified in the psychological display language has not yet been realized.

In addition, a histogram of the frequency of occurrence of colors in a color image is created, the color space is divided into a plurality of areas using this histogram, and the areas are integrated one after another in the order of a predetermined frequency. There is known a color image conversion device for converting a color image having the colors
No. 105276). Since this known color image conversion device integrates adjacent areas based on a certain standard,
The resolution of the converted image is lower than that of the input image, and it is inevitable that the image deteriorates.

That is, an image conversion device capable of converting a color natural image according to an image psychologically intended by an operator without degrading the image quality has not yet been provided.

(Problems to be Solved by the Invention) According to the present invention, when an operator instructs psychological image conversion of a color image in a psychological display language, a certain color image is converted into a color image of a psychological image designated by the operator. It is an object of the present invention to provide a color image conversion device capable of easily converting without deteriorating the color image.

Another object of the present invention is to provide a color image psychological language display device capable of displaying a psychological image of a color image on a display device in a psychological display language by analyzing the color image.

A further object of the present invention is to provide a color image conversion and display device having an excellent man-machine interface that can be handled by anyone without requiring any skill in operation.

(Means for Solving the Problems) First Invention A first invention of the present invention relates to an image memory 2 for storing an input or color-converted color image, and an image memory 2 for storing a color image.
Histogram creating means 3 for classifying each pixel of the image read out from each of the divided areas including a predetermined representative color, obtaining and storing the occurrence frequency of each divided area, and the number of the divided area as a pixel according to the classification of the histogram. The divided area storage means 4 which stores the data in association with each other, the color coordinate memory 71 in which a large number of colors are arranged in advance in the psychological coordinate axis associated with the hue, the hue, and the strength, and a large number of psychological display languages are arranged in the psychological coordinate axis in advance A psychological coordinate memory 7 having a psychological language coordinate memory 72, a psychological language selecting means 8 for selecting a psychological display language according to a response from an operator, and a psychological coordinate memory based on a psychological display language selection request from the operator. From the optimal histogram computing means 9 for computing the optimal histogram most suitable for the psychological display language and the histogram created by the histogram creating means 3. A color conversion means 10 for converting the color data in the image memory by comparing the gram and the optimum histogram generated by the optimum histogram calculation means 9; and an image display means 11 for appropriately displaying the contents of the image memory before and after the color conversion. However, the color image conversion device performs color conversion of a color image in response to a psychological image conversion request from an operator.

Second invention A second invention is directed to an image memory 2 for storing a color image.
And a histogram creating means 3 for classifying each pixel of the image read out from the image memory 2 into a divided area including a predetermined representative color, obtaining the occurrence frequency of each divided area, and storing the occurrence frequency.
And a color coordinate memory 71 in which a large number of color arrangements are arranged in advance on a psychological coordinate axis associated with hue, tone and strength, and a psychological language coordinate memory 72 in which a large number of psychological display languages are arranged in advance on the psychological coordinate axis. Psychological coordinate memory 7, a psychological language computing unit 5 for computing and selecting a psychological display language corresponding to an image from the psychological coordinate memory 7 based on the representative color and frequency information from the histogram creating unit, and the computation and selection of the psychological language. A psychological language display means 6 for displaying the result,
It is a color image psychological language display device that displays a psychological image corresponding to an input image in a language to an operator.

Third invention A third invention has a configuration in which the configuration of the first invention and the configuration of the second invention are combined, calculates a psychological image according to an input image, and displays it to an operator. It is a color image conversion / psychological language display device that performs color conversion of an input image in response to a psychological image conversion request from a person.

(Operation) Operation of the first invention The histogram creating means 3 classifies each pixel of the input image into a plurality of divided areas having a constant width centered on a predetermined representative color, and counts the occurrence frequency for each classification. Then, a histogram of the input image is created, and which divided area each pixel is classified is transmitted to the divided area storage means 4. The divided area storage means 4 stores the classified divided area number in association with the pixel. .

When the operator gives an instruction for color conversion in the psychological display language, the psychological language selection means 8 searches the psychological language coordinate memory 72 and reads out the coordinate value of the psychological display language corresponding to the instruction of the operator.

The optimum histogram calculation means 9 calculates an optimum histogram that best fits the coordinate values of the psychological language.

The color conversion unit 10 converts the color data in the image memory by sequentially associating the regions of high frequency in the histogram of the input image with the regions of high frequency in the optimum histogram obtained by the optimal histogram calculation unit 9 in order. Write to 22.

The image display means 11 appropriately displays the contents of the image memory before and after color conversion.

As described above, according to the present invention, the color conversion of the input image can be automatically performed only by instructing the psychological display language of the image level that the operator associates with, and thus the operator can perform the color conversion as in the prior art. A sophisticated man-machine interface can be realized by using the present invention in various color image generation and conversion systems without the need for complicated adjustment using the rgb signal or the CMY signal.

Operation of the second invention The histogram creating means 3 classifies each pixel of the input image into one of a plurality of regions having a constant width centered on a predetermined representative color, and sets the occurrence frequency for each classification. Count and create a histogram of the input image and store it.

The psychological language computing means 5 searches the color coordinate memory 71 by the area signal (which also indicates the representative color) from the histogram creating means 3 to find the coordinates of each corresponding representative color, and weights the frequency value. The coordinate value representing the input image is determined by calculating the weighted average. Then, the coordinate value of each psychological display language is read from the psychological language coordinate memory 72, and each distance from the coordinate value representing the input image is calculated,
The psychological display language with the shortest distance is selected and displayed by the psychological language display means 6.

According to the present invention, since the image of the color tone of the image can be displayed in a psychological display language, the image of the image can be easily and objectively confirmed by anyone in various color image generation and conversion systems, Therefore, it is not necessary for the operator to have a high level of skill to grasp the image of the image, and an excellent man-machine interface can be realized.

Operation of the Third Invention The third invention can provide an operation having both the operation of the first invention and the operation of the second invention. Further, according to the third aspect of the present invention, the input image or the image after color conversion stored in the image memory is displayed by the image display means 11, and the psychological images of those images are displayed in the language by the psychological language display means 6. Further, since the color conversion of the image can be performed in accordance with the psychological image conversion request by the psychological display language, the operator can confirm the input image, the converted image and the psychological evaluation of these images by the display means. By performing image conversion operations,
Fine color adjustment can be easily performed, and a more excellent man-machine interface can be realized.

(Embodiment) FIG. 1 is an overall configuration diagram showing a schematic configuration of an embodiment corresponding to the third invention in the present invention. FIG. 2 and FIG. 3 are diagrams showing the operation flow.

In FIG. 1, an input device 1 is a device for inputting a color image, and specifically, a color image input device for optically reading an original image and obtaining image data, such as a color television camera or a color image scanner, or a color image input device. An image storage device such as a magnetic disk that stores image data read by the image input device. Each pixel of the image data output from the input device 1 is composed of M-bit R, G, and B components.

The image memory 2 has an input image memory 21 for storing input image data from the input device 1 and a converted image memory 22 for storing a converted image described later.

The image display device 11 displays the input image data or the converted image data stored in the image memory 2.

The histogram creating means 3 sequentially reads the pixel values of the image data stored in the input image memory 21 and counts the frequency of occurrence of colors, that is, the number of pixels having each color for each representative color area to create an input histogram. It is a thing.

Specifically, in the histogram creating means 3, 2 ^N representative colors ( ₁ ,
₁ , ₁ ) However, i = 1, ..., 2 ^N ) is stored in the representative color memory 31, and R that covers the entire range of input pixel values,
The G and B spaces are divided by S ₁ (,,) i = 1, ..., 2 ^N in the following equation.

S ₁ (,,) = {r, g, b ₁ −ΔR ₁ ≦ r ≦ ₁ + ΔR
₁ , ₁₋ ΔG ₁ ≦ g ≦ i + ΔG ₁ , ₁₋ ΔB ₁ ≦ b ≦
₁ + ΔB ₁ } (1) Each pixel value (r, g, b) of the input image data read from the input image memory 21 is sequentially determined by the area determining means 32 in the histogram creating means 3. The divided areas R ₁ ± ΔR ₁ , G ₁ ± ΔG ₁ , B ₁ ± centered on each representative color according to the above formula (1)
It is determined by comparison with ΔB ₁ which divided region belongs, and the region number i (see FIG. 4) that indicates the determined region is determined. Then, the frequency counting means 33 in the histogram creating means 3 increases the count value corresponding to each of the determined region numbers i, that is, the frequency value W ₁ , and finally shows the input image corresponding to FIG. A table of such histograms is created.

Further, the histogram creating means 3 sends the frequency W ₁ (i = 1, 2, ..., 2 ^N ) of the histogram as shown in FIG. The area number i indicating whether the area is counted is sequentially transmitted to the divided area storage means 4.

The divided area storage means 4 has a divided area memory having an address corresponding to the address of the input image memory 21, and the area number i sent from the histogram creating means 3 is divided based on the address of the input image memory 21. Store in area memory. That is, the area number i of each pixel is stored in the divided area memory at the address position corresponding to each pixel stored in the input image memory 21. FIG. 5 schematically shows the input image memory and the divided area memory. R, G, and M, which are M bits at each address position of 3 Mbit length of the input image memory, are shown.
The pixel value of each color of B is stored, and correspondingly, an N-bit area number is stored at each address position of the divided area memory.

The area number data stored in the divided area memory is referred to when the content of the input image memory 21 is converted by the color conversion means 10 described later.

The psychological language calculation means 5 uses the psychological coordinate memory 7 based on the count value (frequency value) W ₁ transmitted from the histogram creation means 3.
The psychological coordinate value representing the input image is calculated by referring to the color coordinate memory 71 in the inside, and then the psychological language which is most suitable for the psychological coordinate value is selected by referring to the psychological language coordinate memory 72, and the psychological language display is performed. It is transmitted to the means 6.

The psychological coordinate memory 7 conducts a color image investigation on what kind of impression each color has from the viewpoint of hue and hue, that is, a psychological effect, and carries out a factor analysis based on the investigation data. However, the basic image is used as a scale to create a P-dimensional space, and the colors are psychologically differentiated to position the individual colors to create a new psychological solid space.

This psychological coordinate memory 7 is a color coordinate memory that stores a color coordinate map that maps the relationship between color and basic image scale.
71 and a psychological language coordinate memory 72 that stores a psychological language coordinate map that maps the psychological display language to the same basic image scale
Consists of In this embodiment, P = 2, that is, a color coordinate map and a psycholinguistic coordinate map known from Japanese Patent Publication No. 56-46082 having two basic image scales are used.

The color coordinate map, as shown in FIG. 6 cited from the above publication, uses 2 ^N colors, which are the representative colors in the histogram creating means 3, as the basic image warmth.
And warm-cool, which expresses the degree of coldness and coolness, and soft-hard, which expresses the degree of softness and hardness (hard), on the axis
It is a map plotted on two axes.

On the other hand, the psychological language coordinate map is a map of q pre-selected psychological display languages on the same basic image scale as the color coordinate map, as shown in FIG. 7 cited from the above publication.

By using these maps in combination, equivalent conversion from a color to a psychological display language or from a psychological display language to a color can be performed.

First, the psychological language calculation means 5 first creates the histogram creation means 3
The color coordinate memory 71 is referred to by using the area number i and the frequency W ₁ output by the above, and the coordinate value on the basic image scale representing the input image is determined by the calculation of the equation (2).

That is, the representative color R ₁ from the histogram creating means 3,
G ₁ , B ₁ However, the color coordinate memory 71 is searched with a signal indicating i = 1, ..., 2 ^N ), that is, the area number i, and coordinate values X ₁ , Y ₁ corresponding to the area number i on the color coordinate map. (X is warm-cool axis, Y
Represents the coordinate value of the soft-hard axis), and then the coordinate value X, Y representing the input image, Is determined by the calculation of

Next, the psychological language operation means 5 uses the psychological language coordinate memory 7 to calculate the coordinate values X and Y thus determined by the operation of the equation (2).
Coordinate values a _j , b of q psychological display languages placed on 2
_j (where a _j and b _j are the warmth-cool of the jth psychological display language
Axis, which represents the coordinate value on the soft-hard axis), and selects the psychological display language with the smallest distance. That is, the optimum psychological display language for the input image is obtained by the calculation of the following expression (3).

The psychological display language f (X, Y) representing the input image thus determined is displayed by the psychological language display means 6 and presented to the operator.

The operator compares the input image displayed on the image display means 11 with the psychological display language displayed on the psychological language display means 6 to determine whether or not to convert the input image, and when the conversion is desired, the desired image is selected. The user selects the psychological display language from the psychological display language in the psychological language coordinate map to request conversion. Expressed in the psychological display language arranged in the psychological language coordinate map shown in FIG. 7, this process requires conversion of an input image of “natural” image into an image of “chic” image, for example. is there.

The psychological language selection means 8 outputs the corresponding coordinate value on the basic image scale according to the psychological display language of the image conversion request instructed by the operator. Specifically, for the operation, the psychological language coordinate memory 72 is searched using the psychological display language requested by the operator as a number, the coordinate values registered therein are retrieved, and transmitted to the optimum histogram computing means 9.

The optimum histogram calculation means 9 is the histogram means 3
Psychology corresponding to the conversion request image from the psychological language selection means 8 based on the frequency value W ₁ output from the color coordinate memory 71 and the color coordinate values X ₁ and Y ₁ of the 2 ^N representative colors read from the color coordinate memory 71. Language coordinate value, the best approximate coordinate that best approximates Frequency value W _1p , color coordinate value (X _1p , Y in the histogram of
_1p ) to obtain the correspondence between the divided area number i and the area number i'for converting the color of the divided area number i into the color of the area number i '.

In order to convert the histogram of the input image into a histogram suitable for the psychological display language instructed by the operator, in the present embodiment, the representative colors that are more important for the designated color conversion are arranged in the descending order of the frequency value W ₁ of the input image. (That is, the order of increasing distance between the coordinate value and the coordinate value of the representative color in the color coordinate memory).

Therefore, the optimum histogram calculation means 9 executes the following operation.

(1) The distance d ₁ between the coordinate values X ₁ and Y ₁ of the representative color of 2 ^N colors read from the color coordinate memory 71 and the coordinate value of the psychological display language of the conversion request instruction from the psychological language selection means 8 is calculated by the following equation. Calculate by d ₁ = calculated ^{_{{(X 1 - 2 - 2}} + (Y 1} 1/2 ............... (5) (2) Step of divided area number i corresponding to the coordinate values X _1, Y ₁ Sorted in ascending order of distance d ₁ .
The divided area numbers sorted in ascending order by sorting are i ′
Then, the order ip of this i ′ (that is, the numbers newly added in ascending order to the rearranged divided area number i ′ in the order of 1, 2, 3, ...) Is the color in the order of contributing to the image requested for conversion. Coordinate values X _1p , Y obtained by rearranging coordinate values X _{1 '} , Y _1'
It represents the order of _1p . The order of the divided area numbers sorted in ascending order by this sort is stored. That is, the correspondence between ip and the divided area number i'is stored.

(3) The divided area numbers i are sorted in the order of the measure of the frequency W ₁ created by the histogram creating means 3. Order of divided area numbers i sorted in ascending order by sorting
ip (that is, the numbers newly assigned in ascending order to the rearranged divided area number i, 1, 2, 3, ...) is obtained by rearranging the color coordinate values X ₁ and Y ₁ in the order of contributing to the image of the input image. Represents the order of the coordinate values X ₁ and Y ₁ . The order of the divided area numbers sorted in ascending order by this sort is stored. That is, the correspondence between ip and the divided area number i is stored.

(4) Obtain the correspondence between the numbers i and i'from the correspondence between the numbers ip and i'stored in step (2) and the correspondence between the numbers ip and i stored in step (3). , The correspondence is stored.

(5) Based on the correspondence between the number i and the number i'stored in step (4), the number i'is sequentially increased from 1 to 2 ^N, and the corresponding number i'is used as the converted divided region number. It is sent to the conversion means 10.

The color conversion means 10 sets 2 ^2N pairs of color conversion coefficient sets A _{1,1 ′} having a predetermined (1,1 ′) as a two-dimensional address. It has a color conversion coefficient memory in which is stored.

The coefficient set A _{1,1 '} satisfies the following equation.

The color conversion means 10 first uses ^2N pairs of coefficient sets A ₁ from the color conversion coefficient memory with the signal (i, i ') representing the correspondence between the divided area numbers i and i'transmitted from the optimum histogram calculation means 9 as an address. _, 1'is selectively read.

Therefore, the pixel data (r, g, b) of the input image are sequentially read from the input image memory 21, and the divided area storage means 4 is also used.
The divided area number i corresponding to the pixel is sequentially read from. Then, the pixel data (r,
g, b) is multiplied by the color conversion coefficient A _{1,1 '(i} ) to generate converted pixel data (r', g ', b').

The converted image data is written in the converted image memory 22 and displayed by the image display means 11.

In this embodiment, the signal read from the image memory is RG
Although described as the B signal, other color space signals L * a
* B *, L * u * v *, Munsell HVC, etc. can be handled in the same manner.

Further, in this embodiment, the basic image axes in the psychological coordinate memory 7 are two axes, but if more accurate conversion is required, more axes may be provided.

(Effect of the Invention) According to the color image conversion apparatus of the present invention, the color conversion of the input image can be automatically performed by instructing the image-level psychological display language associated with the human from the operator, and accordingly the operation is performed. The person does not need to perform complicated adjustment using the rgb signal or the CMY signal as in the prior art, and can use the present invention in various color image generation conversion systems to realize an advanced man-machine interface. .

In addition, according to the color image psychological language display device of the present invention, since the image of the color tone of the image can be displayed in the psychological display language, the image of the image can be objectively and to whom in various color image generation and conversion systems. However, it can be easily checked, so that the operator is not required to have a high level of skill to grasp the image of the image.
An excellent man-machine interface can be realized.

Further, according to the color image conversion / psychological language display device of the present invention in which the psychological language display device and the color image conversion device are combined, the image display means 11 displays the input image stored in the image memory or the image after color conversion. And the psychological images of those images are displayed by the psychological language display means 6
Can be displayed in a language, and the color of the image can be converted in response to a psychological image conversion request in the psychological display language. Therefore, the operator can display the input image, the converted image, and the psychological evaluation of these images on the display means. By performing the image conversion operation while confirming, the fine adjustment of the color can be easily performed, and a more excellent man-machine interface can be realized.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing a schematic configuration of an embodiment of the present invention. 2 and 3 are diagrams showing the operation of the apparatus of the embodiment shown in FIG. FIG. 4 is a table showing the histogram in the present invention. FIG. 5 is a diagram showing a storage configuration of the image memory and the divided area memory. FIG. 6 is a diagram showing a color coordinate map in which ^2N colors, which are the representative colors, are plotted on two axes of a basic image, that is, a warm-cool axis and a soft-hard axis. Is. FIG. 7 is a diagram showing an example of a psychological language coordinate map in which q preselected psychological display languages are mapped on the same basic image scale as the color coordinate map. 1 ... Image input device, 2 ... Image memory, 3 ... Histogram creating means, 4 ... Divided area storage means, 5 ... Psychological language computing means, 6 ... Psychological language display means, 7 ... Psychological coordinate memory, 8 ... Psychological language selecting means , 9 ... Optimal histogram calculation means, 10 ... Color conversion means, 11 ...
Image display means.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshie Goto 2274 Hongo, Ebina City, Kanagawa Fuji Zerox Co., Ltd. Ebina Business Office (56) Reference JP-A-64-84386 (JP, A) JP-A-61- 262978 (JP, A)

Claims (3)

(57) [Claims] 1. An image memory for storing an input image or an image after color conversion, and each pixel of the image read out from the image memory is classified into a divided area having a predetermined representative color, and the occurrence frequency for each divided area. Histogram creating means for obtaining and storing, a divided area storage means for storing the number of divided areas in association with pixels according to the classification of the histogram, and a large number of color schemes in advance on the psychological coordinate axes associated with hue, hue, and strength. A psychological coordinate memory having an arranged color coordinate memory and a psychological language coordinate memory in which a large number of psychological display languages are previously arranged on the psychological coordinate axis, and a psychological language for selecting a psychological display language according to a response from an operator. Optimal histogram that best fits the psychological display language from the psychological coordinate memory based on the selection means and the psychological display language selection request from the operator. Optimal histogram computing means for computing, color conversion means for transforming color data in the image memory by comparing the histogram and the optimal histogram, and image display means for appropriately displaying the contents of the image memory before and after the color conversion. A color image conversion device, comprising: a color image conversion device for performing image color conversion in response to a psychological image conversion request from an operator. 2. An image memory for storing a color image, and a histogram for classifying each pixel of the image read out from the image memory into divided areas having a predetermined representative color, and obtaining and storing the occurrence frequency of each divided area. Creating means, a color coordinate memory in which a large number of color arrangements are arranged in advance on a psychological coordinate axis associated with hue, tone and strength, and a psychological language coordinate memory in which a large number of psychological display languages are arranged in advance on the psychological coordinate axis. A psychological coordinate memory provided, a psychological language operation unit for operating and selecting a psychological display language corresponding to the image from the psychological coordinate memory based on the representative color and frequency information from the histogram creating unit, and displaying the psychological language operation result And a psychological language display means for displaying the psychological image of the color image to the operator in a psychological display language. Language display device. 3. An image memory for storing an input image or an image after color conversion, and each pixel of the image read out from the image memory is classified into divided areas including a predetermined representative color, and the occurrence frequency of each divided area is determined. Histogram creating means for obtaining and storing, divided area storage means for storing the number of divided areas in association with pixels according to the classification of the histogram, and a large number of color arrangements are arranged in advance on the psychological coordinate axes associated with hue, hue, and strength. A color coordinate memory, and a psychological coordinate memory having a psychological language coordinate memory in which a large number of psychological display languages are arranged in advance on the psychological coordinate axes, and a representative color of the histogram, and from the psychological coordinate memory based on frequency information. A psychological language calculation means for calculating / selecting a psychological display language corresponding to the image; a psychological language display means for displaying the psychological language calculation result; Psychological language selection means for selecting a psychological display language according to the response from the author, and optimal histogram calculation means for computing the optimal histogram that best fits the psychological display language from the psychological coordinate memory based on the psychological display language selection request from the operator. A color conversion unit that converts color data in the image memory by comparing the histogram with the optimum histogram; and an image display unit that appropriately displays the contents of the image memory before and after the color conversion. A color image conversion / psychological language display device characterized in that an image is calculated and displayed to the operator in a psychological display language, and color conversion of the image is performed in response to a psychological image conversion request from the operator.