JP2001238067A - Method and device for processing picture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve quality of a mosaic picture formed by sticking a material picture. SOLUTION: The area of a priority picture in an original picture is designated (S41). The original picture is divided into plural tile areas to decide whether each of the plural divided tile areas includes the area of the priority picture and the most similar material picture is selected from among plural material pictures and stuck preferably to a tile area decided to include the area of the priority picture (s42). To the other tile areas, the most similar material picture is selected from among plural non-selected material pictures and stuck (s34).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image processing method and apparatus for generating a mosaic image by combining a plurality of material images.

[0002]

2. Description of the Related Art A mosaic is "a combination of small pieces of various colors such as stone, glass, marble, etc., fitted on a floor, a wall, etc., and designed, or a technique thereof" (Sanseido)
It has been widely known as the Modern Japanese Dictionary). By using this technique, it is possible to form a mosaic image by combining a large number of photographic images to form a certain design or one photographic image.

[0003]

When such a mosaic image is created, the original image is divided into a plurality of areas (tiles), and a material image (tile) constituting the mosaic image is formed in each of the plurality of areas. Image) to create a mosaic image. In this case, a material image of a color close to the color of the divided area of the original image is selected from a plurality of material images and pasted.

At this time, if there is no material image having a color very similar to the color of each region (tile), there is a problem that the image quality of a mosaic image formed using those material images is reduced. Was.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned prior art, and has been made by preferentially selecting and allocating a material image to be allocated to a specified partial area of an original image, and allocating another material image to a non-priority area. It is an object of the present invention to provide an image processing apparatus and method for improving the quality of a formed image.

[0006]

In order to achieve the above object, an image processing apparatus according to the present invention has the following arrangement.
That is, an image processing apparatus that creates an image imitating an original image by combining a plurality of material images selected from a plurality of material images, and a designating unit that designates a partial area in the original image; Dividing means for dividing into a plurality of areas, and similar image selecting means for selecting the most similar material image from the plurality of material images preferentially with respect to the area specified by the specifying means It is characterized by.

[0007] To achieve the above object, the image processing method of the present invention comprises the following steps. That is, combining a plurality of material images selected from a plurality of material images,
An image processing method for creating an image imitating an original image,
A designation step of designating a partial area in the original image; a division step of dividing the original image into a plurality of areas; and preferentially to the area designated in the designation step, from among the plurality of material images, A similar image selecting step of selecting a similar material image.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

[First Embodiment] FIG. 1 is a block diagram showing a schematic configuration of an image processing apparatus according to an embodiment of the present invention.

In FIG. 1, reference numeral 101 denotes a CPU, and a RAM
The operation of the entire apparatus is controlled in accordance with the program stored in the storage unit 105. A keyboard 102 is used by a user together with a mouse or the like as a pointing device 102a, and is used to input various data to this device. Reference numeral 103 denotes a display unit, for example, a CRT
And liquid crystal. A ROM 104 and a RAM 105 store programs used in the apparatus and various data. Reference numeral 106 denotes a hard disk device, a floppy disk 107 or a CD-ROM (not shown).
It stores programs and data installed from a drive or the like. The hard disk device 106 and the floppy disk device 107 also constitute an external storage device used for the file system of the image processing device. Reference numeral 108 denotes a printer, such as a color inkjet printer or an electrophotographic printer.

The hard disk device 106 stores a plurality (P) of tile images serving as constituent elements of the mosaic image. According to a program described later, M × N images selected from the tile images are stored in FIG. As shown in (1), a mosaic image is created by arranging and combining M images in the horizontal direction and N images in the vertical direction. The mosaic image thus created is stored as an image file in the hard disk device 106, or displayed on the CRT 103, or output to the printer 108 and printed.

FIG. 3 is a diagram showing the relationship between a plurality of types of images used in the mosaic method according to the present embodiment.

Referring to FIG. 3, an image 201 is a pattern or an image which is an original when an image is formed by using a mosaic method. The image 202 is an image configured using a plurality of small images (tiles) by a mosaic method. The material image 203 is a material image used to compose the image 202, and it is assumed here that P sheets are prepared. The number P of these material images is generally large enough to prepare the types of colors and textures necessary to form the image 202.

Although the size of each of the P material images 203 is set to be the same as the size of the tile for the sake of explanation, the size of each material image does not necessarily need to match the size of the tile. , And all P sheets need not be the same size. When the size of each material image is different as described above, it is necessary to convert the size of the material image 203 when pasting the material image 203 on the corresponding tile. Here, the number of sheets P is a number sufficiently larger than the above-mentioned M × N sheets.

FIG. 4 is a view showing an example in which the image 201 is divided into 4 × 5 tiles. The number of pixels in the horizontal direction of the image 201 is X, the number of pixels in the vertical direction is Y, The number of pixels is indicated by p and the number of pixels in the vertical direction is indicated by q (X = 4p,
Y = 5q). Each tile has a TL according to its position.
(X, y: x = 0 to 3, y = 0 to 4).

FIG. 5 shows a case where the image 201 is a color image.
Each tile is shown as being composed of red (R), green (G), and blue (B) color planes.

FIG. 6 is a flowchart showing a general flow of a mosaic image generating method in the image processing apparatus according to the present embodiment. A program for executing this processing is stored in the above-described hard disk 106 and executed. Sometimes loaded into the RAM 105 and executed by the CPU 01.

First, in step S41, when the image 201 is divided into a plurality of regions (tiles), the operator assigns a region (tile) to which a material image is to be preferentially allocated among the plurality of regions to the keyboard 102 or a pointing device. 10
Interactive selection using 2a or the like. Next, step S4
Proceed to 2 and the designated high priority area (tile)
Is assigned to a certain material image and pasted to the area (tile). Next, the process proceeds to step S43, and step S4
In low priority areas (tiles) not specified in 1,
Assign and paste a certain material image.

Hereinafter, the operation of each step in FIG. 6 will be described in detail.

[Explanation of Step S41] Step S41
Then, the original image 201 is displayed on the screen 1002 of the display unit 103, and the priority area is interactively selected using the keyboard 102 or the like. At this time, an image corresponding to the image 201 is displayed on the display unit 103, for example, as shown in FIG. Reference numeral 1001 denotes an “Exit button”, which is clicked by pointing to this button 1001 with the cursor 1005 which is instructed to move by the pointing device 102a, thereby terminating step S41 and shifting control to step S42.

In FIG. 7, 1003 and 1004 are
9 shows an example of a priority area selected according to an operation by an operator.

At this time, the operator looks at the original image 201 displayed on the screen 1002 and designates an image area to which a material image is to be preferentially assigned using the pointing device 102a or the like. In general, the original image 201 is not uniformly important as a whole. For example, in the case of a face image as shown in FIG. 7, it is considered that eye reproduction is particularly important for image quality. Image area 1 corresponding to
003 and 1004 are designated.

In the generation of a mosaic image, the plurality of material images 203 are limited resources. Therefore, an important image area in the original image is designated, and the material image is preferentially assigned to the important image area. on the other hand,
The quality of the entire mosaic image can be improved by selecting and assigning the remaining material images to the unimportant image regions.

In the image area designated as having a high priority, flag information such as a priority flag corresponding to each pixel is set.

[Detailed Description of Step S42] FIG.
14 is a flowchart showing a flow of a process of selecting and pasting a material image having the closest average density from a plurality of material images to an image region designated as having a high priority in step S41.

First, in step 81, the original image 201 is
It is divided into × N areas (tiles). As a result of this split,
For example, as shown in FIG.
× N rectangular tiles TL (0,0), TL (1,0),
TL (2,0), ..., TL (2,4), TL (3,3)
It is divided into 4). In FIG. 4, X and Y indicate the numbers of pixels of the image 201 in the horizontal and vertical directions, respectively, and p and q
Indicates the number of pixels of each tile in the horizontal and vertical directions. Therefore, the following relationship holds: X = p × M, Y = q × N. Here, for the sake of simplicity, it is assumed that all tiles have the same size, but this is not always necessary in the present embodiment.

FIG. 5 is a diagram showing the data structure of each area. Each area has p × q primary colors, red (R), green (G),
Decomposed into blue (B).

Then, the process proceeds to a step S82, where R, G, and B are respectively determined for each of the P material images according to the following equation.
Is calculated and stored in the RAM 105.
When the average densities of these material images are obtained in advance and stored for each of these material images, it goes without saying that this calculation is unnecessary.

Rs-av = ΣRi / (p × q) Gs-av = ΣGi / (p × q) Bs-av = ΣBi / (p × q) where s-av is a source (source: material image) Mean of Rs-av, Gs-av and Bs-av, respectively.
The average density of each of red, green, and blue in each material image is shown. Σ indicates the sum of i = 0 to (pq−1).

Then, the process proceeds to a step S83, wherein counters Xpos (0≤Xpos≤M-1) indicating the position of the tile area, Ypo
Based on s (0 ≦ Ypos ≦ N−1), the tile area is checked sequentially from the tile area (tile TL (0,0)) at the upper left corner of the image 201, and the priority flag is set in the tile area. That is, it is checked whether the tile area includes the priority area specified in step S41.
If it is not the priority area, the process proceeds to step S87. If it is included (if it is the priority area), the process proceeds to step S84, and the average density of the tile area is obtained. This is obtained according to the following equation.

Rd-av = ΣRi / (p × q) Gd-av = ΣGi / (p × q) Bd-av = ΣBi / (p × q) where d-av is destination (original image 201) , And Rd-av, Gd-av, and Bd-av each indicate the average density of red, green, and blue in each tile. Σ indicates the sum of i = 0 to (pq−1).

Then, the process proceeds to a step S85, wherein a material image having the smallest difference from the average density of the tile area is selected from the P material images. This selection method is, for example, RG
The distance ΔE of the B3 stimulus value is calculated, and the one with the smallest value is selected. The evaluation formula is shown below.

ΔE = (Rs-av-Rd-av) ^ 2 + (Gs-av-Gd-a
v) ^ 2 + (Bs-av-Bd-av) ^ 2 Here, "(Rs-av-Rd-av) ^ 2" is (Rs-av-Rd-a
v) represents the square.

Based on this evaluation formula, a material image having the smallest ΔE is selected from the P material images.

Next, the flow advances to step S86 to store the selected material image as a used material image (material image used in the priority area).

Next, in step S87, the area (tile) of the target image 201 is moved to the next position, and the image 2
It is determined whether or not the processing for all the tile areas 01 has been completed. If the processing has not been completed, the process returns to step S83, and the above processing is repeatedly executed.

[Detailed Description of Step S43] In step S43, a material image is selected for a tile for which no material image has been selected and pasted in step S42, ie, a tile which has not been selected as a priority area.

FIG. 9 is a flowchart for explaining the processing for a tile area other than the priority area in step S43.

First, in step S91, the aforementioned step S
83, a counter X indicating the position of the tile area
pos (0≤Xpos≤M-1), Ypos (0≤Ypos≤N-
Based on 1), the tile area is sequentially examined from the tile area (tile TL (0, 0)) at the upper left corner of the image 201, and whether or not the above-mentioned priority flag is set in the tile area, that is, the tile It is determined whether the area includes the priority area specified in step S41. If the area is the priority area, the process for the tile area has been completed, so the process proceeds to step S94.
Proceeding to 92, the average density of the tile area is determined. This is obtained in the same manner as in step S84 described above.

Next, in step S93, a material image having an average density closest to the average density of the tile area is selected from unused material images that are not used in the priority area, and the material image is assigned to that material image. Paste in the tile area.

This selection method is based on the distance Δ of the RGB3 stimulus values.
E is calculated and the one with the smallest value is selected. The evaluation formula is shown below.

ΔE = (Rs-av-Rd-av) ^ 2 + (Gs-av-Gd-a
v) ^ 2 + (Bs-av-Bd-av) ^ 2 Based on this evaluation formula, a material image having the smallest ΔE is selected from material images not used in the priority area. Then, the process proceeds to step S94 to check whether the process has been completed for all the material images. If not, the process returns to step S91 to perform the same process as described above for the next tile area.

[Other Embodiments] In the above embodiment, an example has been described in which an operator interactively determines an important region in an image, but the present invention is not limited to this.

For example, as described above, when a face image is used as an original image, it is possible to mechanically discriminate generally important areas such as eyes, nose, mouth, etc. using a known face recognition technique. Since it is possible, the above processing can be automated. In addition, if an important area in an image can be automatically determined using a scene recognition and analysis technique, the image area may be set as a priority area.

Even if there is an error in determining whether or not the image area is important, the quality of the mosaiced image is only adversely affected, and does not become a fatal obstacle.

Alternatively, the interactive selection of the important area and the automatic selection may be combined. For example, some important area candidates are presented to the operator by automatic selection, and the operator
Any of them may be selected. Or
The important region by the automatic selection may be presented to the operator first, and the operator may judge it. If the region is correct, the process proceeds to the next step. If there is a problem, the region may be interactively selected again.

[Other Embodiments] In the present invention, a plurality of devices (for example, a host computer, an interface device,
The present invention may be applied to a system including a reader, a printer, or the like, or may be applied to an apparatus (for example, a copying machine, a facsimile machine, or the like) including one device.

Further, an object of the present invention is to supply a storage medium (or a recording medium) on which a program code of software for realizing the functions of the above-described embodiments is recorded to a system or an apparatus, and a computer (a computer) of the system or the apparatus. Alternatively, the present invention is also achieved when a CPU or an MPU reads and executes a program code stored in a storage medium. In this case, the program code itself read from the storage medium implements the functions of the above-described embodiment, and the storage medium storing the program code constitutes the present invention. When the computer executes the readout program codes, not only the functions of the above-described embodiments are realized, but also an operating system (OS) running on the computer based on the instructions of the program codes. This also includes a case where some or all of the actual processing is performed and the functions of the above-described embodiments are realized by the processing.

Further, after the program code read from the storage medium is written into the memory provided in the function expansion card inserted into the computer or the function expansion unit connected to the computer, the program code is read based on the instruction of the program code. , The CPU provided in the function expansion card or the function expansion unit performs part or all of the actual processing,
The case where the function of the above-described embodiment is realized by the processing is also included.

As described above, according to the present embodiment, a region considered to be particularly important in an image is selected as a priority region, and an optimal material image is preferentially selected in a tile region including the priority region. By selecting and pasting, the quality of the mosaic image can be improved.

[0051]

As described above, according to the present invention, a material image to be assigned to a designated partial area of an original image is preferentially selected and assigned, and another material image is assigned to a non-priority area. There is an effect that the quality of the formed image can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an image processing apparatus according to an embodiment.

FIG. 2 is a diagram illustrating a mosaic image.

FIG. 3 is a diagram illustrating a process of generating a mosaic image.

FIG. 4 is a diagram illustrating an example of area division of an original image.

FIG. 5 is a diagram illustrating a color configuration of individual tiles forming a mosaic image.

FIG. 6 is a flowchart illustrating a flow of a mosaic image generation process according to the present embodiment.

FIG. 7 is a diagram illustrating designation of a priority area using a display screen according to the present embodiment.

FIG. 8 is a flowchart illustrating a process of selecting and pasting a material image to a priority image area in the image processing apparatus according to the present embodiment.

FIG. 9 is a flowchart illustrating a process of selecting and pasting a material image to a non-priority image area in the image processing apparatus according to the present embodiment.

Claims (17)

[Claims] 1. An image processing apparatus for creating an image imitating an original image by combining a plurality of material images selected from a plurality of material images, a designating means for designating a partial area in the original image, Dividing means for dividing the original image into a plurality of areas; preferentially for the area specified by the specifying means,
An image processing apparatus comprising: a similar image selecting unit configured to select a most similar material image from the plurality of material images. 2. The image processing apparatus according to claim 1, further comprising a calculating unit that calculates an average density of each of the plurality of material images. 3. The similar image selecting means has an arithmetic means for calculating an average density of the area, and calculates an average density of each area calculated by the arithmetic means and an average density of each of the plurality of material images. The image processing apparatus according to claim 1, wherein a material image to be assigned to the area is determined according to a difference. 4. The image selecting means has a calculating means for calculating an average density of the area, and the average density of a determined area not including the partial area calculated by the calculating means, and the similar image The image processing apparatus according to claim 1, wherein a material image to be assigned to the area is determined according to a difference between respective average densities of a plurality of material images not selected by the selection unit. 5. The image processing apparatus according to claim 1, wherein the designation unit includes a display unit that displays the original image, and a unit that designates a partial area of the image displayed by the display unit. The image processing device according to any one of claims 1 to 4. 6. The image processing apparatus according to claim 1, wherein said specifying means has means for automatically determining and specifying a partial area of said original image. 7. The image processing apparatus according to claim 1, further comprising: a determination unit configured to determine whether each of the plurality of regions divided by the division unit includes a partial region designated by the designation unit. 4. The method according to claim 1, wherein the most similar material image is selected from a plurality of material images that have not been selected by the similar image selecting device for the region determined to include the partial region by the determining device. 7. The image processing device according to any one of 6. 8. An image selection unit that selects a material image most similar to a region determined not to include the partial region by the determination unit from among a plurality of material images not selected by the similar image selection unit. The image processing apparatus according to claim 7, further comprising a unit. 9. An image processing method for creating an image simulating an original image by combining a plurality of material images selected from a plurality of material images, comprising: a designation step of designating a partial area in the original image; A dividing step of dividing the original image into a plurality of regions; and a similar image selecting step of selecting a material image most similar from the plurality of material images preferentially to the region specified in the specifying step. An image processing method comprising: 10. The image processing method according to claim 9, further comprising a calculating step of calculating an average density of each of the plurality of material images. 11. The similar image selecting step includes a calculating step of calculating an average density of the area, and calculating an average density of each area calculated in the calculating step and an average density of each of the plurality of material images. 11. The image processing method according to claim 9, wherein a material image to be assigned to the area is determined according to the difference. 12. The image selecting step includes a calculating step of calculating an average density of the area, wherein the average density of a determined area that does not include the partial area calculated in the calculating step is different from the similar density. The image processing method according to claim 9, wherein a material image to be assigned to the region is determined according to a difference between respective average densities of a plurality of material images not selected in the image selecting step. 13. The method according to claim 9, wherein the specifying step includes a displaying step of displaying the original image, and a step of specifying a partial area of the image displayed in the displaying step. The image processing method according to any one of the above. 14. The image processing method according to claim 9, wherein said specifying step automatically determines and specifies a partial area of said original image. 15. The method according to claim 15, further comprising: determining whether each of the plurality of areas divided in the dividing step includes a partial area specified in the specifying step. 10. The most similar material image is selected from a plurality of material images not selected in the similar image selecting step for an area determined to include the partial area in the determining step. 15. The image processing method according to any one of 14. 16. An image selecting step of selecting a most similar material image from a plurality of material images not selected in the similar image selecting step for an area determined not to include the partial area in the determining step. The image processing method according to claim 15, further comprising: 17. A computer-readable storage medium storing a program for executing the image processing method according to claim 9. Description: