JPH0228892A - Picture synthesizer - Google Patents

Abstract

PURPOSE:To obtain an optimum mixed pattern in a short time and to obtain a synthetic picture without needing the recalculation of attribute information by obtaining the mixed conditions (mixed coefficient) of the mixed area of the picture near a boundary part for synthesizing the picture from the combination of the attribute information and the mixed pattern. CONSTITUTION:The outputs of a background picture memory 11 and an insert picture memory 12 are inputted to a synthesizing arithmetic part 13. Selective information to make an output when synthesized into a background picture or an insert picture is stored in a mask memory 15 and the selective information (boundary information) is inputted from a boundary designation input part 18. The mask memory 15, further, stores distance information (attribute information) from the boundary by the operation of a CPU 16. In the synthesizing arithmetic part 13, by the mixed conditions outputted from a conditional table 17, an weighting addition is executed to the picture data outputted from the background picture memory 11 and the insert picture memory 12 and the synthetic picture is generated and stored into a synthetic picture memory 14.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to an image composition device that composes a plurality of halftone images.

(Prior Art) As a conventional technique for synthesizing two images consisting of pixels of light and dark shading, there is a technique that mixes the density values of the two images at a ratio according to the attribute information of the pixels (Japanese Unexamined Patent Application Publication No. 1983-1992-1). 140
T74, JP-A-59-133865, etc.).

For example, distance information from the boundary of two images is used as this attribute information, and the density values of the two images are mixed while gradually changing at a ratio according to the distance (by combining the two images). Obtained image (hereinafter referred to as composite image)
It is possible to suppress sudden changes in density at the boundary between images to eliminate visual discomfort, and to obtain a special effect in which two images appear to blend together.

(Problem to be Solved by the Invention) However, in the above-mentioned conventional technology, it is necessary to change the mixing condition pattern (hereinafter referred to as a mixing pattern) for mixing two images, such as the ratio to attribute information, and redo the synthesis. In this case, it is necessary to recalculate attribute information such as distance, which has the disadvantage that it takes a huge amount of time to find the optimal mixture pattern.

The present invention aims to eliminate the drawbacks of the prior art as described above. In other words, the present invention is applicable to image synthesis in which multiple images are mixed as a function of attribute information of each pixel, and once some of the attribute information is obtained, when the mixing pattern is changed and the synthesis is performed again, it is possible to The purpose of this invention is to provide a device that allows an operator to easily obtain the desired composite image by finding the optimal mixing pattern in a short time without having to recalculate attribute information such as .

(Means for Solving the Problems) As shown in FIG. 1, the present invention comprises a boundary setting means 1 for setting a boundary between a first image and a second image to be synthesized, and attribute information of pixels (e.g. , distance from the boundary, transparency, etc.) and storage means 2 for calculating and storing the attribute information, and mixing pattern setting means 3 for setting the area and density distribution pattern for mixing the first image and the second image. , a mixing condition determining means 4 that determines a mixing condition based on the output of the attribute information calculation storage means 2 and the output of the mixing pattern setting means 3; This image synthesizing device includes an image synthesizing means 5 which obtains a synthesized image by mixing two images.

(effect) FIG. 2 is a diagram showing the flow of operation of the present invention.

First, the boundary setting means 1 sets the boundary of which image is to be fitted into which part of the target composite image area (FIG. 2). Based on the boundary (region) information set by the boundary setting means 1 and the input image information, attribute information of pixels such as distance from the boundary between the first image and the second image, transparency, etc. It is calculated and stored by the arithmetic storage means 2 (FIG. 2).

Further, the mixing pattern setting means 3 has a plurality of mixing patterns that specify the area where the first image and the second image coexist (melting area), density distribution, etc., and selects one of the mixing patterns as desired. Selectively set the pattern (Fig. 2 ■).

The mixing condition determining means 4 determines a mixing condition for specifying a mixing ratio for mixing the density values of two images based on the attribute information calculated by the attribute information calculation storage means 2 and the mixing pattern information set by the mixing pattern setting means 3. Calculate (second
Figure ■).

The image synthesizing means 5 receives the density values of the first image and the second image, and synthesizes the first image and the second image based on the mixing condition from the mixing condition determining means 4 (second image). Figure ■).

When the operator looks at the obtained image and is not satisfied with the connection at the boundary of the image, such as when unnaturalness is noticeable, the operator changes the settings of the mixing pattern setting means 3 and instructs to synthesize again. This process can be repeated until a satisfactory composite image is obtained (Fig. 2 (■)). When composing an image using the specified new mixing pattern, previously calculated attribute information can be used. Therefore, it becomes possible to easily obtain a composite image desired by the operator in a short time.

(Example) The present invention will be described in detail below using an example in which the distance from the boundary is used as attribute information.

FIG. 3 is a block diagram of this embodiment. In the figure, a background image memory 11 stores a background image (first image) that becomes a background during composition, and an inset image memory 12 stores a background image (first image) that becomes a background during composition.
This is an inset image memory that stores an inset image to be combined with the second image). The outputs of the background image memory 11 and the inset image 12 are respectively input to the composition calculation section 13.

The mask memory 15 stores selection information as to whether the combined output is a background image or an inset image, and this selection information (boundary information) is input from the boundary setting section 18. The mask memory 15 also stores distance information (attribute information) from the boundary, which is calculated by the CPU 16. The mixing condition table 17 is a rutsup table from which corresponding mixing conditions (mixing coefficients) are read based on the mixing pattern specified by the operator via the setting parameter input section 19 and the distance information output from the mask memory 15. The contents of the mixed condition table 17 can be rewritten by the CPU 1B as necessary. The composition calculation unit 13 weights and adds image data output from the background image memory 11 and the embedded image memory 12 according to the mixture conditions output from the mixture condition table 17, and generates a composite image. The output is stored in the composite image memory 14.

FIG. 4 is a diagram showing an example of the vicinity of the boundary in the mask memory 15 in this embodiment. In Fig. 4, one grid surrounded by a dotted line represents mask information for one pixel, and pixels with a numerical value of O in the grid are areas where the background image is displayed, and pixels with a numerical value of 1 or more in the grid are , is the area where the inset image is displayed, and the solid line represents the boundary between the background image and the inset image. Further, the numeric values of 1 or more within the grid represent the distance from the boundary toward the inside of the fitted image.

If the mask information for one pixel in the mask memory 15 is composed of 3 bits, the distance can be expressed in 8 ways from 0 to 7, and even if the actual distance is 8 or more, the distance in the mask memory 15 is It is expressed as a distance of 7.

These distances are obtained by providing information specifying the boundary between the background image and the embedded image from the boundary specification input section 18 and calculating it in the CPU 1B.

FIG. 5 shows an example of table information of the mixed condition table 17. The mixing condition table 17 is composed of seven mixing condition patterns (mixing patterns), one mixing pattern is selected according to the setting parameters specified by the operator, and the mixing pattern is further selected based on the distance information input from the mask memory 15. Each mixing condition inside is read out. This mixing condition is output to the synthesis calculation section 13. In the example of FIG. 5, if the setting parameter is L1 distance D, the mixing condition is determined by the following equation.

However, in the case of ■, K=1.

The L+1 compositing operation unit 13 performs the following compositing operation for each pixel using the mixing condition K from the mixing condition table 17.

Io = (1-K)IA+K I[l (2
) In formula (2), I. is the pixel density of the composite image, IA is the pixel density of the background image, and I8 is the pixel density of the embedded image.

FIG. 6 is a diagram showing how the density changes at the boundary when the mixing pattern of setting parameter 2 is selected in the mixing condition table shown in FIG.

In this mixing pattern of setting parameter 2, the fifth
As shown in the figure, when the distance is O, the mixing condition becomes =0,
From equation (2), Io=IA.

When the distance is 1, the mixing condition is =0.33, and when the distance is 2, the mixing condition is =0.87, and from equation (2), Io = 0.33 I, +0.67 IB.

When the distance is 3 or more, the mixing condition becomes =1, and the pixel density of the composite image is determined using the mixing condition K.

If the density of the background image is set to a constant value IA and the density of the inset image is set to a constant value IB, a composite image in which the density gradually changes from the boundary as shown in FIG. 6 will be obtained.

In this embodiment, the attribute information is the distance from the boundary, but it is also possible to use other than distance, for example, transparency as the attribute information.

A second example in which the transparency is used as attribute information will be described. Transparency here refers to how the background looks when seen through the relatively transparent foreground. For example, if there is a glass window with a uniform blue background, if light is shining on the glass window, the blue background seen through the glass window will be different from the one without the glass window due to the degree of reflection. Become. At this time, the blue component is detected and made transparent, and when compositing another object on the other side of the glass,
By utilizing this transparency, it is possible to perform natural-looking image composition. In this case, a composite image with desired transparency can be quickly obtained using the same configuration as in FIG. To this end, in the second embodiment, transparency information is stored in the mask memory 15, and ratio coefficients for determining the mixing conditions based on this transparency information are provided in the mixing condition table 17. In the mixing condition table 17, "distance" in the table of FIG. 5 is replaced with "transparency".

By specifying a setting parameter (pattern number) and selecting a mixing pattern, it is easy to perform image synthesis while changing the transparency.

Although the two embodiments have been described above, they can be further modified in various ways.

For example, the mixture pattern is not fixed, and it is also possible to register a new mixture pattern in the process of finding the optimal mixture pattern, and to perform synthesis using this newly registered mixture pattern.

In addition, although the mixing conditions stored in the mixing pattern are ratio coefficients as shown in equation (2) in the embodiment, it is not necessarily necessary to use such a ratio, and the combination calculation unit 13 also uses ratio coefficients other than equation (2). The composition operation can be performed using the function of , and the formula (2
) as Io=F (IA, IB, K) (3) F:
Like any function - it can be made into a film.

(Effects of the Invention) As explained above, according to the present invention, the mixing conditions (mixing coefficients) of the mixing area of images near the boundary for image synthesis
is configured so that it can be obtained from a combination of attribute information and a mixture pattern, so if you want to redo the composition, remember the attribute information of the pixel obtained first, and reset +2- only for the mixture pattern to be combined with the attribute information. Therefore, it is possible to obtain the mixing conditions for performing the composition operation, and there is no need to repeatedly calculate the mixing conditions including attribute information, which is time-consuming as in the prior art.

Therefore, according to the present invention, a desired composite image can be easily obtained in a short time.

Further, according to the present invention, only attribute information such as distance, which can be kept in a relatively small number of bits, is stored corresponding to each of the many pixels that make up the image.
Information that requires a large number of bits, such as mixed conditions, can be stored as a common pattern in a lookup table, etc., so when melting is only performed at a short distance from the boundary, it is possible to store mixed conditions as attributes. Compared to storing information pixel-by-pixel, the memory capacity can be significantly reduced.

[Brief explanation of the drawing]

Figures 1 and 2 are block diagrams showing the basic configuration of the invention.
The figure is an operation flow diagram for explaining the operation in Figure 1,
4 is a block diagram showing the configuration of an embodiment of an image synthesis device according to the present invention; FIG. 4 is a diagram showing the storage state of attribute information near the boundary of an image in the mask memory in the embodiment of FIG. 3; The figure shows an example of the contents of the mixing condition table, and FIG. 6 is a diagram showing how the density is gradually changed near the boundary in this embodiment. ■... Boundary escape means, 2... Attribute information calculation storage means, 3... Mixed pattern escape means, 4... Mixing condition determining means, 5... Image synthesis means, 11... Background image Memory, 12...Inset image memory, 13...Composition operation section, 14...Composition image memory, 15...Mask memory, 16...CPU 117...Mixing condition table, 18...Boundary Specification input section, 19... Setting parameter input section. Patent Applicant Fuji Xerox Co., Ltd. Representative Patent Attorney Noboru Iwa Figure Composite Image Figure 2 Figure 4 Figure 5 Figure 6 Distance

Claims (1)

[Claims] Boundary setting means for setting a boundary between a first image and a second image to be combined; attribute information calculation storage means for calculating and storing attribute information of pixels; mixing pattern setting means for setting a region and density distribution pattern for mixing the two images; mixing condition determining means for determining a mixing condition based on the output of the attribute information calculation storage means and the output of the mixing pattern setting means; , according to the mixing condition outputted by the mixing condition determining means, the first
and a second image to obtain a composite image.