JP3454714B2 - Image splicing method and apparatus, and storage medium storing program - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention synthesizes overlapping portions of first and second binary images with digital first and second binary images having adjacent arrangement relations and having overlapping portions. hand,
The present invention relates to an image joining processing method for joining a first binary image and a second binary image, an apparatus therefor, and a storage medium recording a program.

[0002]

2. Description of the Related Art When a large-sized original is read by a scanner or the like to obtain a digital binary image (black and white image),
In order to obtain a binary image NG with a higher resolution, for example, as shown in FIG. 17, the reading of the original OG by the scanner is performed in a divided manner, and the binary images NG obtained by the division are read.
A method of joining A and NGB by post-treatment is adopted.

In FIG. 17, the original OG is placed in the X direction (for example,
The figure shows the case where the reading is performed by dividing in the main scanning direction). The first binary image NGA is a binary image obtained by reading the image in the first reading area OGA in the original OG, and the original O
G and the scanner head 100a in the Y direction of the drawing (for example,
It is obtained by moving it relative to the sub-scanning method). Further, the second binary image NGB has a second reading area O in the original OG.
It is a binary image obtained by reading an image in GB, and is obtained by relatively moving the original OG and the scanner head 100b in the Y direction in the drawing.

Further, the first and second read areas OGA,
The first and second binary images NG by overlapping a part of OGB
Include the same image part OW of the original OG in A and NGB,
The first binary image NGA is created by synthesizing the overlapping portion WA (pixel range of width WW in the X direction) in each binary image NGA, NGB.
And the second binary image NGB are connected to each other.

In the joint processing of the first and second binary images NGA and NGB in the above-mentioned method, conventionally, as shown in FIG. 18, the joint position KL is set in the overlapping portion WA and the joint position KL is set. As a boundary, the first binary image NGA
And the second binary image NGB are simply combined.

[0006]

However, the conventional example having such a structure has the following problems. For example, when the original OG is divided and the binary image is read as shown in FIG. 17, for example, the relative movement of the original OG and the scanner head 100a in the Y direction and the relative movement of the original OG and the scanner head 100b in the Y direction. From the relative movement of the first and second binary images NGA and NGB
The image may be shifted in the direction.

As described above, in the state where the first binary image NGA and the second binary image NGB are misaligned with each other, the first binary image NGA and the second binary image NGB are formed by the conventional method. When and are joined together, there is a problem in that the images in the joined portion are conspicuously misaligned in the joined image NG, and the images cannot be joined together with high accuracy.

The present invention has been made in view of the above circumstances, and an image stitching processing method capable of accurately stitching images even if there is an image shift between the first and second binary images. And its device and a storage medium storing a program.

[0009]

The present invention has the following constitution in order to achieve such an object. That is, the invention according to claim 1 synthesizes the overlapping portions of the first and second binary images with the first and second digital binary images of the adjacent arrangement relationship having the overlapping portions. First
Of the first binary image belonging to the composite area including at least a part of the overlapping portion, in the pixel row in the joining direction. Corresponding to the result of applying the first mixing ratio that reduces the weight of the pixel on the second binary image side to the density data of each pixel, and the pixel row in the joining direction of the first binary image. A second mixture ratio for reducing the weight of the pixel on the first binary image side is applied to the density data of each pixel belonging to the composite area in the pixel row in the connecting direction of the second binary image. The first step of performing a process of adding the combined result for each corresponding pixel and combining the pixels for each pixel column in the connecting direction, and each of the connecting directions in the connecting direction belonging to the combining region combined in the first step A second smoothing process is performed on the density data of each pixel in the pixel row. And a third step of binarizing the density data of each pixel in each pixel row in the connecting direction belonging to the composite area that has been smoothed in the second step by thresholding And a fourth step of joining the first binary image and the second binary image including the result of binarization in the third step.

According to a second aspect of the present invention, the overlapping portions of the first and second binary images are combined with the adjacent digital first and second binary images having an arrangement relation having the overlapping portions. And an image stitching processing device that stitches the first binary image and the second binary image together, the stitching direction of the first binary image belonging to the synthesis area including at least a part of the overlapping portion. Second density data for each pixel in the pixel row of
And the result of applying the first mixing ratio in which the pixel load on the binary image side becomes smaller, and the second mixing direction of the second binary image corresponding to the pixel row of the first binary image in the connecting direction. The result of applying a second mixture ratio, which reduces the weight of the pixel on the first binary image side, is added to the density data of each pixel belonging to the composite area in the pixel row, for each corresponding pixel. And a smoothing process for the density data of each pixel in each pixel row in the joining direction belonging to the above-mentioned synthesis area that is synthesized by the synthesizing means. And a threshold value process is performed on the density data of each pixel in each pixel row in the joint direction belonging to the composite area that has been subjected to the smoothing process by the smoothing process unit. And a threshold processing means for converting the threshold value to 2 An image stitching means for stitching, including phased results first binary image and a second binary image, those having a.

According to a third aspect of the present invention, the overlapping portions of the first and second binary images are combined with the digital first and second binary images having the adjacent arrangement relationship and having the overlapping portions. A storage medium storing a program for causing a computer to execute an image stitching process that stitches the first binary image and the second binary image, and the storage medium includes at least a part of the overlapping portion. As a result of applying a first mixture ratio that reduces the weight of the pixel on the second binary image side to the density data of each pixel in the pixel row in the connecting direction of the first binary image belonging to the region And for the density data of each pixel belonging to the composite area in the pixel row in the joining direction of the second binary image corresponding to the pixel row in the joining direction of the first binary image, the first 2 Operates the second mixture ratio that reduces the pixel weight on the value image side A first step of performing a process of adding the combined result for each corresponding pixel and combining the pixels for each pixel column in the connecting direction, and a process of combining in the combining direction belonging to the combining area combined in the first step. A second step of performing a smoothing process on the density data of each pixel in the pixel array;
The third step of performing thresholding on the density data of each pixel in each pixel row in the connecting direction belonging to the composite area which has been subjected to the smoothing processing in the step of binarizing; A program for causing a computer to execute a process including the step of connecting the first binary image and the second binary image including the result of binarizing in the step of It was recorded.

[0012]

The operation of the image stitching method according to the first aspect of the present invention is as follows. First, in the first step,
The density data (of “0” and “1” of each pixel in the pixel row in the joining direction of the first binary image belonging to the composite area including at least a part of the overlapping portion of the first and second binary images The result of applying a first mixing ratio that reduces the weight of the pixel on the second binary image side to the binary density data);
Density data (binary density of “0” and “1”) of each pixel belonging to the above-mentioned composite area in the pixel row in the connecting direction of the second binary image corresponding to the pixel row in the connecting direction of Data)) and the result of applying the second mixture ratio, which reduces the weight of the pixel on the first binary image side, for each corresponding pixel, and the process of combining is performed for each pixel in the connecting direction. Do column by column.

The pixel rows in the connecting direction are the first and second pixel rows.
2 is a row of pixels arranged in the arrangement direction of the binary image. This first
By the step of, the density data of each pixel in each pixel row in the connecting direction belonging to the combined area after combining can be multivalued.

Next, in a second step, smoothing processing is performed on the density data of each pixel in each pixel row in the connecting direction belonging to the above-mentioned combination area that is combined in the above-mentioned first step. This smoothing process is performed by, for example, a well-known filter process that performs a weighted average of several peripheral pixels. By this second step, the density data of each pixel in each pixel row in the connecting direction belonging to the synthesis area can reflect the density data of the peripheral pixels and increase the gradation of multi-valued.

Next, in a third step, threshold value processing is performed on the density data of each pixel in each pixel row in the connecting direction belonging to the above-mentioned composite area which has been smoothed in the above-mentioned second step. Go and binarize. In this threshold processing, the density data of each pixel in each pixel row in the joining direction belonging to the multi-valued composite area is set to “0” with a predetermined threshold as a boundary,
This is a process of converting into a binary value of "1". By this third step, the multi-valued density data of each pixel in each pixel row in the joining direction belonging to the composite area is returned to binary (“0”, “1”).

Then, in the fourth step, the first binary image and the second binary image including the result of the binarization in the third step are joined together.

An image stitching processing apparatus according to a second aspect of the present invention is an apparatus for suitably implementing the image stitching processing method according to the first aspect, and its operation is as follows.

The synthesizing means belongs to the synthesizing area including at least a part of the overlapping portion of the first and second binary images.
The result of applying a first mixing ratio that reduces the weight of the pixel on the second binary image side to the density data of each pixel in the pixel row in the connecting direction of the value images, and the first two The weight of the pixel on the first binary image side with respect to the density data of each pixel belonging to the composite area in the pixel column of the second binary image in the connecting direction corresponding to the pixel column of the connecting direction of the value image 2. The image stitching method according to claim 1, wherein a process of adding and synthesizing a result obtained by applying a second mixture ratio for which each pixel becomes smaller is performed for each corresponding pixel column in the stitching direction. The first step is performed.

The image joining process according to claim 1, wherein the smoothing processing unit performs the smoothing process on the density data of each pixel in each pixel row in the joining direction that belongs to the combining area combined by the combining unit. The second step of the method is performed.

The threshold value processing means performs threshold value processing on the density data of each pixel in each pixel row in the connecting direction belonging to the combined area which has been smoothed by the smoothing processing means, and performs binary processing. Then, the third step of the image stitching processing method according to claim 1 is performed.

The image joining means includes the first binary image and the second binary image including the result of binarization by the threshold processing means.
The fourth step of the image joining processing method according to claim 1 is performed by joining the value images.

According to the third aspect of the present invention, by causing the computer to read the program recorded in the storage medium, the computer executes the image connecting process according to the method invention of the first aspect.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a functional block diagram showing the configuration of an image stitching processing apparatus according to an embodiment of the present invention.

The image stitching processing device 1 shown in FIG. 1 includes an original image storage device 11, a synthesizing means 12, a smoothing processing means 13,
A threshold processing means 14, an image joining means 15, a processed image storage device 16, a setting instruction device 17 and the like are provided.

For example, the original image storage device 11 is adjacent to the original image storage device 11 and has an overlap portion WA provided by inputting an input device 2 such as a scanner shown in FIG. One or a plurality of sets of digital first and second binary images NGA and NGB having an arrangement relationship are stored. The first and second binary images NG to be joined, which are stored in the original image storage device 11.
For A and NGB, combining means 12 and smoothing processing means 1
3, threshold processing means 14, image joining means 15
By combining images as will be described later, the overlapping portion WA of the first and second binary images NGA and NGB is combined to combine the first binary image NGA and the second binary image NGB. Then, the processed image NG is stored in the processed image storage device 16.

When the original image storage device 11 stores a plurality of sets of the first and second binary images NGA and NGB to be joined, the first and the first instructions given from the setting instruction device 17 are performed. The two binary images NGA and NGB are joined together.

FIG. 2 is a block diagram showing a concrete hardware configuration of the image stitching processing apparatus shown in FIG.

In the configuration of FIG. 2, the CPU 21 for executing various programs and the memory 2 for storing various data.
2, a storage device 23 such as a hard disk, a driver 25 that reads and writes digital data from and to a storage medium 24 such as a floppy disk or a CD-ROM, and a setting instruction such as a keyboard or a mouse that gives various setting instructions to the operator. The device 17 and the like are provided, and if necessary, a communication device 27 such as a modem that transmits and receives data via the communication medium 26, a display device 28, and the like are also provided. In addition,
Reference numeral 29 in FIG. 2 indicates a bus, and 30 indicates an input / output interface.

The image stitching processing program installed from the storage medium 24 storing the image stitching processing program and stored in the storage device 23 is read out to the memory 22, or the storage medium 24 storing the image stitching processing program is read. The image joining process program is loaded into the driver 25 and is read from the storage medium 24 into the memory 22, and the CPU 21 executes the program, whereby the synthesizing unit 12, the smoothing processing unit 13, and the threshold value. Image joining processing is executed by the processing means 14 and the image joining means 15.

The CPU 21 constitutes a synthesizing means, a smoothing processing means, a threshold value processing means, and an image joining means in the invention described in claim 2.

The storage medium 24 storing the image stitching processing program corresponds to the storage medium storing the program in the third aspect of the invention.

For example, the input device 2 is provided from the input device 2 in a state where it is directly connected to the device 1, or the communication medium 2
6 or the input device 2 via the communication device 27, or the first and second binary images NG to be joined.
A and NGB are stored in the storage device 23 and the storage medium 24. Further, the first and second binary images NGA and NGB are stored in the storage medium 24 by the input device 2, and the storage medium 2 is stored.
4 is loaded into the driver 25 and the first and second binary images N
GA and NGB may be given to the device 1.

The CPU 21 stores the first and second binary images NG to be connected (instructed by the setting instruction device 17) stored in the storage device 23 or the storage medium 24.
A and NGB are read into the memory 22, and the first and second
The binary images NGA and NGB are joined together as will be described later, and the joined image NG is stored in the storage device 23 or the storage medium 24 from the memory 22.

That is, the memory 22 and the storage device 2
3. The storage medium 24 corresponds to the original image storage device 11 and the processed image storage device 16 of the device configuration of FIG.

The stitched image NG stored in the storage device 23 or the storage medium 24 is used when the CPU 21 executes various image processing programs or is given to another device to be used by that device. It is used for image processing that is performed.

The CPU mounted on the input device 2 is
The first and second binary images NGA and NGB that have been read may be configured to perform the image stitching process according to the present invention. In that case, the input device 2 is the invention according to claim 2. The CPU which is also used as the image stitching processing device according to the present invention and which is mounted on the input device 2 constitutes the synthesizing means, the smoothing processing means, the threshold value processing means and the image stitching means in the invention according to claim 2. The storage medium storing the image stitching processing program executed by the CPU mounted on the input device 2 corresponds to the storage medium storing the program according to the present invention.

Next, the image stitching processing method of the present invention will be described with reference to the functional block diagram shown in FIG. 1 and the processing conceptual diagrams shown in FIGS.

First, the synthesizing means 12 includes the synthesizing area SA (width in the X direction) including at least a part of the overlapping portion WA (pixel range of the width WW in the X direction) of the first and second binary images NGA and NGB. First binary image NGA belonging to SW pixel range)
Pixel column GLAi (i =
, 2, ..., Y _MAX ) each pixel G (jA, i) (jA
= XA, (XA + 1), ..., (XA + (SW-1)),
However, for each pixel G (jA, i), the first mixture ratio MRA that reduces the weight of the pixel on the side of the second binary image NGB is applied to the density data (XA is determined by the synthesis area SA). As a result of acting together, RTAi and the first 2
Each pixel G (jB, i) (jB = jB = jB = iB) belonging to the combination area SA in the pixel string GLBi in the connecting direction of the second binary image NGB corresponding to the pixel column GLAi in the connecting direction of the value image NGA.
For the density data of XB, (XB + 1), ..., (XB + (SW-1), where XB is determined by the composition area SA), the pixel load on the first binary image NGA side becomes smaller. A process of multiplying the mixture ratio MRB of 2 for each pixel G (jB, i) and operating it, and adding RTBi to each corresponding pixel G (jA, i), G (jB, i) to synthesize them. To each pixel column GLAi, GLBi in the connecting direction.
And the first step is performed.

By the first step, the density data of each pixel G1 (k, i) (k = 1, 2, ..., SW) in each pixel row GLM1i in the connecting direction belonging to the combined area SA after combining is obtained. It can be multi-valued.

The composite area SA may be an area including at least a part of the overlapping part WA, and a part of the overlapping part WA may be the combining area SA or the entire overlapping part WA may be the combining area SA. Good.

Further, the first and second mixing ratios MRA, MRB
May gradually change the mixing ratio as shown in FIGS. 5 (a) and 5 (b), or may change the mixing ratio stepwise to some extent as shown in FIGS. 5 (c) and 5 (d). You may let me. However, the first and second mixture ratios MRA and MRB are set so that the total of the corresponding pixels becomes “1.0”.

Returning to FIG. 1 and FIG. 3, next, the smoothing processing means 13 causes each pixel in each pixel row GLM1i in the joint direction belonging to the synthesis area SA synthesized by the synthesis means 12 (first step). The smoothing process is performed on the density data of G1 (k, i) to perform the second step. This smoothing processing is, for example, a well-known filter that performs weighted averaging of several pixels around each target pixel G1 (k, i) with each pixel G1 (k, i) in each pixel column GLM1i as a target pixel in sequence. Do by processing. By this second step, the density data of each pixel G2 (k, i) in each pixel row GLM2i in the connecting direction belonging to the synthesis area SA reflects the density data of the peripheral pixels and becomes a multilevel gradation. Can be increased.

The smoothing process in the second step is shown in FIG.
As shown in (a), the weighted average of the pixel of interest G1 (k, i) and the pixels on the left and right of the pixel of interest G1 (k, i) is used by using only the pixels in the pixel row GLM1i in the connecting direction. Alternatively, as shown in FIG. 6B, the pixel row GL in the connecting direction including the target pixel G1 (k, i).
Weighted averaging of the pixel of interest G1 (k, i) and its surrounding pixels (pixels in the processing area FA) is performed using the pixels in M1i and the pixels in the pixel columns before and after the pixel column GLM1i. May be. Further, using the pixels in the pixel rows before and after the pixel row GLM1i in the connecting direction including the pixel of interest G1 (k, i), the pixel of interest G1 (k, i) and the pixels above and below it (FIG. 6B). G1 (k, i-1), G1 (k, i +)
Weighted averaging with 1)) may be performed.

The same weight may be set for all the pixels to be processed, or the weight of the target pixel may be set to be the largest and the load may be set to be smaller as the distance from the target pixel increases.

Further, although m = 3 in FIG. 6A, m = 5, 7, ... May be used. Also in FIG. 6B, m
Xn = 3 × 3, but m × n = 5 × 5, 7 × 7,
May be ... Even when the weighted average of the pixel of interest G1 (k, i) and the pixels above and below it is performed, n is not limited to 3 and n
= 5, 7, ...

Further, in FIG. 6A, G1 (1,
When i) is the target pixel, the target pixel G1 (1,
i) and several pixels on the right side thereof may be used to perform weighted averaging, and the pixel on the left side of the target pixel G1 (1, i) may be the first pixel.
Weighted averaging may be performed by supplementing from the binary image NGA. In FIG. 6A, when G1 (SW, i) is the target pixel, similarly, the weighted average may be performed using the target pixel G1 (SW, i) and several pixels on the left side thereof.
The pixel on the right side of the target pixel G1 (SW, i) is set to the second pixel
Weighted averaging may be performed by supplementing from the value image NGB. In FIG. 6B, similarly, when the peripheral pixel in the synthesis area SA is set as the target pixel, similarly, the weighted average is performed using a part of the pixels in the processing area to be weighted averaged, or the right and left of the target pixel are compared. Regarding the pixels, the first and second binary images NGA, N
It suffices to replenish necessary pixels from GB and perform weighted averaging. When performing weighted averaging of the pixel of interest G1 (k, i) and the pixels above and below it, G1 (k, 1) and G1
Even when (k, Y _MAX ) is the target pixel, the weighted average may be performed using some pixels in the processing area for weighted average.

Returning to FIG. 1 and FIG. 3, next, the threshold value processing means 14 belongs to the combining area SA which has been subjected to the smoothing processing by the smoothing processing means 13 (second step), in the joint direction. Threshold processing (f {G2 (k, i), SL}) on the density data of each pixel G2 (k, i) in the pixel GLM2i column.
Are binarized to perform the third step. This threshold value processing (f {G2 (k, i), SL}) is performed with G2 (k, i) (concentration data)> with a predetermined threshold value SL as a boundary.
When SL, G3 (k, i) (density data of) is set to “1”, and when G2 (k, i) (density data) ≦ SL, G3
(K, i) (density data of) is set to “0”, and each pixel column GL2i in the connecting direction belonging to the multi-valued composite area SA
The density data of each pixel G2 (k, i) in the
This is a process of converting into a binary value of "1". By this third step, each pixel row GL in the connecting direction belonging to the composite area SA
The multi-valued density data of each pixel G2 (k, i) in 2i is returned to binary (“0”, “1”), and each pixel row GL3i in the connecting direction belonging to the composite area SA is obtained. .

Then, the image joining means 15 binarizes the result R by the threshold processing means 14 (third step).
The first binary image NGA and the second binary image N including TX
The images are combined with GB to obtain the combined image NG.

As the program executed by the CPU 21, the processing can be realized by the following procedure, for example.

(1) After the first step is performed on all the pixel columns in the connecting direction, the second to fourth steps are sequentially performed on the entire synthesis area SA.

(2) FIG. 6 shows the smoothing process of the second step.
As shown in (a), when processing is performed using only the pixels in the pixel row in the connecting direction that includes the target pixel,
The fourth step is sequentially repeated for each pixel column i = 1 to Y _MAX in the connecting direction.

(3) The smoothing process in the second step is shown in FIG.
As shown in (a), when processing is performed using only the pixels in the pixel row in the connecting direction that includes the target pixel,
The third step is sequentially repeated for each pixel column i = 1 to Y _MAX in the connecting direction, and the fourth step is performed using the processing result RTX.

Next, a concrete processing example will be described with reference to FIGS.
Will be described with reference to. In this example, as shown in FIG. 7A, it is assumed that an image including a diagonal line exists in the overlapping portion WA of the original OG. The first and second binary images N obtained by dividing and reading the image portion OGQ including the diagonal lines of the original OG.
It is assumed that the images of GA and NGB are displaced in the Y direction as shown in FIGS. 7B, 7C, and 8.

The first and second binary images NGA, NGB
If the image is joined by the conventional method, as shown in FIG. 9 and FIG. 7D, the image NG after the joining is conspicuously misaligned in the joined portion, and the joining of the images cannot be performed accurately. Recognize.

Next, the first and second binary images NGA, NG
A case where B is joined by the image joining process according to the present invention will be described.

In this case, the area in which the central 10 pixels of the overlapping area WA (WW is 20 pixels) is SW is the composite area SA.
Process as. Further, the first step is performed using the first and second mixing ratios MRA and MRB as shown in FIG. Further, in the smoothing process of the second step, only the pixels in the pixel row in the connecting direction including the target pixel are used, and a total of 3 pixels, that is, the target pixel and each of the left and right 1 pixels of the target pixel, The weight of the pixel on the left side: the weight of the pixel of interest: the weight of the pixel on the right side of the pixel of interest = 1: 2: 1 is averaged. Further, in the threshold value processing of the third step, the threshold value SL is set to "0.5".

The results of the first step are shown in FIG. 11, the results of the second step are shown in FIG. 12, the results of the third and fourth steps are shown in FIG.
Each is shown in FIG. As shown in FIG. 13 and FIG. 7E, according to the image stitching processing method of the present invention, even if the first and second binary images NGA and NGB have image deviations, It can be seen that smooth image stitching can be performed on the image NG with no noticeable image shift, and accurate image stitching can be realized.

As is clear from the above processing result, according to the image stitching process according to the present invention, in the first step, each pixel row in the stitching direction corresponding to each of the first and second binary images is formed. After the results of applying the first and second mixture ratios are added and combined, and the binary image is multi-valued, in the second step, smoothing processing is performed to obtain density data of peripheral pixels. Reflecting the increase in the gradation of multi-valued, in the third step, threshold processing is performed to return to a binary image, and in the fourth step, the first result including this binarized result is included. Since the processing is performed so that the binary image and the second binary image are joined together, even if the first and second binary images are misaligned, the images after joining are not misaligned. Conspicuous and smooth stitching of images can be performed, and accurate stitching of images can be realized. Kill.

Further, as shown in FIG. 14A, among the pixels in the pixel row of the first binary image NGA belonging to the composite area SA in the joining direction, the pixel is closer to the second binary image NGB side. The input device 2 that captures the first binary image NGA for each pixel
The distortion of the optical system (the optical system in the scanner head 100a) becomes large. Similarly, as shown in FIG. 14B, among the pixels in the pixel row in the joining direction of the second binary image NGB belonging to the combination area SA, the pixel closer to the first binary image NGA side , The distortion of the optical system (the optical system in the scanner head 100b) of the input device 2 that takes in the second binary image NGB becomes large.

Therefore, the first mixture ratio MRA to be applied to the density data of each pixel in the pixel row of the first binary image NGA belonging to the composite area SA in the connecting direction is set to the value on the side of the second binary image NGB. The second mixture ratio MRB, which is set so that the pixel weight is small, and which acts on the density data of each pixel in the pixel row of the second binary image NGB belonging to the combination area SA in the joining direction, is set to By setting the weight of the pixel on the binary image NGA side to be small and combining the two, the distortion of the optical system of the input device 2 is reduced, and the first binary image NGA belonging to the combination area SA is connected. The density data of each pixel in the pixel row in the horizontal direction and the density data of each pixel in the pixel row in the connecting direction of the second binary image NGB belonging to the combining area SA can be combined to combine the images. Can improve accuracy .

The first and second binary images NGA, NG
Not only when the B image is displaced in the Y direction, but for example,
When the original OG floats in the overlapping portion OW of the first and second reading areas OGA and OGB in FIG. 17, the original OG floats due to the distortion of the optical system in each of the scanner heads 100a and 100b. The image of the part that is
The first and second binary images NGA and NGB may be displaced in the X direction. Even in such a case, according to the image joining process of the present invention, the first and second binary images NG
A and NGB can be accurately connected.

The image joining process according to the present invention is not limited to the case of joining the first and second binary images NGA and NGB obtained by dividing the original OG into two as shown in FIG. Digital first and second binary images NG with adjacent arrangement relations having overlapping portions obtained in various forms
It can be applied when A and NGB are connected.

For example, as shown in FIG. 15, the original OG is divided into three or more by the scanner head 100 (in FIG.
When the four binary images NG1 to NG4 that have been read are connected to each other, for example, the binary images NG1 and NG2 are the first and second binary images NGA. , NGB, and the binary images NG3 and NG4 are combined into the first and second two images.
Binary image N stitched together as value images NGA and NGB
Binary image in which G1 and NG2 are joined together, and binary image N
Binary images obtained by joining G3 and NG4 can be joined together as first and second binary images NGA and NGB. Further, for example, first, the binary images NG1 and NG2 are joined together, the joined binary image and the binary image NG3 are joined together, and the joined binary image and the binary image NG4 are joined together. Also, the order of joining can be appropriately selected.

Further, for example, as shown in FIG. 16, it is also possible to connect the binary images NG1 to NG4 obtained by scanning the original OG in a plane, and the connecting direction is 1 in the Y direction (or the X direction). Not limited to the dimensional direction, it is possible to connect the binary images by appropriately setting the two-dimensional direction.

[0065]

As is apparent from the above description, according to the image stitching processing method of the first aspect of the present invention, the first and second binary images belonging to the composite area including the overlapping portion are included. The result of applying the first mixture ratio that reduces the weight of the pixel on the second binary image side to the density data of each pixel in the pixel row of the binary image of 1 Of the density data of each pixel belonging to the composite area in the pixel row in the joint direction of the second binary image corresponding to the pixel row in the joint direction of the binary image of A process of adding the result of applying the second mixture ratio having a smaller load to each corresponding pixel and synthesizing is performed for each pixel column in the joining direction, and each pixel column in the joining direction belonging to the combining region. Each pixel in the connecting direction that belongs to the composite area by converting the density data of each pixel in the The density data of each pixel in the pixel is subjected to a smoothing process, and the density data of each pixel in each pixel row in the joint direction belonging to the composite area is converted into a multi-valued layer by reflecting the density data of the surrounding pixels. After increasing the tones, the threshold data is binarized for the density data of each pixel in each pixel row in the joint direction that belongs to the composite area that has been subjected to the smoothing process, and the binarized result Including the first binary image and the second
Since the image is processed so as to be joined with the binary image of, even if the first and second binary images have an image shift, the image after the stitching has a smooth image with no noticeable image shift. It is possible to perform stitching, and it is possible to realize accurate stitching of images.

In the first step, the first mixing ratio applied to the density data of each pixel in each pixel row in the connecting direction of the first binary image belonging to the composite area is set to the second binary value. The pixel weight on the image side is set to be small, and the first mixture ratio is applied to the density data of each pixel in each pixel row in the joining direction of the first binary image belonging to the composite area. The result and the second mixture ratio that acts on the density data of each pixel in each pixel row in the connecting direction of the second binary image belonging to the composite area are set so that the weight of the pixel on the first binary image side is small. The density data of each pixel belonging to the composite area in the pixel row in the joint direction of the second binary image corresponding to the pixel row in the joint direction of the first binary image is set to Since the result of applying the mixture ratio is added and combined for each corresponding pixel, the first and second pixels are combined. Distortion of the optical system of the input device that has read the images can be reduced, and the corresponding pixel rows in the joining direction of the first and second binary images can be combined, and the joining accuracy of the images can be improved. You can

According to the second aspect of the present invention, it is possible to realize an image stitching processing apparatus that preferably implements the image stitching processing method of the first aspect.

According to the third aspect of the invention, it is possible to cause a computer to execute the image connecting process according to the method invention of the first aspect.

[Brief description of drawings]

FIG. 1 is a functional block diagram showing a configuration of an image stitching processing device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a specific hardware configuration of the image stitching processing device shown in FIG.

FIG. 3 is a processing conceptual diagram for explaining an image stitching processing method according to the present invention.

FIG. 4 is a processing conceptual diagram for explaining the first step of the image stitching processing method according to the present invention.

FIG. 5 is a diagram showing first and second mixing ratios.

FIG. 6 is a diagram for explaining smoothing processing.

FIG. 7 is a diagram showing a processing example in which the processing result of the conventional method and the processing result of the present invention are compared.

8 is a diagram showing the density data of each pixel of the first and second binary images in the processing example of FIG.

FIG. 9 is a diagram showing density data of each pixel of a binary image after joining which has been processed by the conventional method in the processing example of FIG.

10 is a diagram showing first and second mixing ratios used in the first step of the image joining process of the present invention in the processing example of FIG.

11 is a diagram showing density data of each pixel as a result of performing the first step of the image joining processing of the present invention in the processing example of FIG.

FIG. 12 is a diagram showing density data of each pixel as a result of performing the second step of the image joining processing of the present invention in the processing example of FIG.

13 is a diagram showing the density data of each pixel as a result of performing the third and fourth steps of the image joining processing of the present invention in the processing example of FIG.

FIG. 14 is a diagram showing a distorted state of an image by an optical system in the input device at the time of reading first and second binary images.

FIG. 15 is a diagram in which the image stitching process according to the present invention can be applied 2
It is a figure which shows the example of a value image.

FIG. 16 is a diagram in which the image stitching process according to the present invention can be applied 2
It is a figure which shows the other example of a value image.

FIG. 17 is a diagram showing an example of an input device for reading the first and second binary images to be joined.

FIG. 18 is a processing conceptual diagram for explaining a conventional image stitching processing method.

[Explanation of symbols]

1: Image stitching processing device 12: Synthetic means 13: smoothing processing means 14: Threshold processing means 15: Image stitching means 21: CPU 22: Memory 24: Storage medium NGA: first binary image NGB: second binary image WA: Overlapping part of the first and second binary images SA: Synthetic area MRA: first mixing ratio MRB: Second mixing ratio

─────────────────────────────────────────────────── --- Continuation of the front page (56) References JP-A-6-141228 (JP, A) JP-A-10-13769 (JP, A) JP-A-9-330396 (JP, A) JP-A-7- 298053 (JP, A) JP-A-9-321972 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H04N 1/38-1/393 G06T 3/00

Claims (3)

(57) [Claims] 1. The first and second binary images are synthesized by combining the first and second digital binary images having an arrangement relationship and having adjacent layouts with each other. Value image and second
An image joining process for joining the binary image of the first binary image belonging to a composite area including at least a part of the overlapping portion with respect to the density data of each pixel in the pixel row in the joining direction. As a result of applying a first mixture ratio that reduces the weight of the pixel on the side of the second binary image,
The weight of the pixel on the side of the first binary image with respect to the density data of each pixel belonging to the composite area in the pixel row in the connecting direction of the second binary image corresponding to the pixel row in the connecting direction of the value image And a result of applying a second mixture ratio for which each pixel becomes smaller, a process of adding and synthesizing corresponding pixels for each pixel column in the joining direction, and a synthesizing process in the first process. A second step of performing a smoothing process on the density data of each pixel in each pixel row in the connecting direction that belongs to the above-described combining region, and belongs to the combining region that is subjected to the smoothing process in the second step. A third step of binarizing the density data of each pixel in each pixel column in the connecting direction by binarization, and a first step including the binarization result of the third step A fourth step of joining the binary image and the second binary image, and An image stitching method characterized by: 2. The first and second binary images, which are adjacent to each other and have a digital arrangement and which have an overlapping portion, are combined to form the first and second binary images. Value image and second
An image joining processing device for joining the binary image of the first binary image belonging to a composite area including at least a part of the overlapping portion to the density data of each pixel in the pixel row in the joining direction. As a result of applying a first mixture ratio that reduces the weight of the pixel on the side of the second binary image,
The weight of the pixel on the side of the first binary image with respect to the density data of each pixel belonging to the composite area in the pixel row in the connecting direction of the second binary image corresponding to the pixel row in the connecting direction of the value image And a result obtained by applying a second mixture ratio for which each pixel becomes smaller, for each pixel corresponding to each other, a synthesizing unit performing the synthesizing for each pixel column in the connecting direction, and the synthesizing region synthesized by the synthesizing unit. Smoothing processing means for performing a smoothing process on the density data of each pixel in each pixel row in the connecting direction belonging to, and each of the connecting direction belonging to the composite area subjected to the smoothing processing by the smoothing processing means. Threshold processing means for performing threshold processing on the density data of each pixel in the pixel array to perform binarization, and first binarization including the result binarized by the threshold processing means. Image stitching that stitches an image and a second binary image Image connecting processing apparatus characterized by comprising: a Align means. 3. The first and second binary images are synthesized by synthesizing the overlapping parts of the first and second digital binary images having an arrangement relationship adjacent to each other and having an overlapping portion. Value image and second
A storage medium storing a program for causing a computer to execute an image stitching process for stitching a binary image of the first binary image belonging to a synthesis area including at least a part of the overlapping portion. The result of applying a first mixture ratio that reduces the weight of the pixel on the second binary image side to the density data of each pixel in the pixel row of
The weight of the pixel on the side of the first binary image with respect to the density data of each pixel belonging to the composite area in the pixel row in the connecting direction of the second binary image corresponding to the pixel row in the connecting direction of the value image And a result of applying a second mixture ratio for which each pixel becomes smaller, a process of adding and synthesizing corresponding pixels for each pixel column in the joining direction, and a synthesizing process in the first process. A second step of performing a smoothing process on the density data of each pixel in each pixel row in the connecting direction that belongs to the above-mentioned combination region, and belongs to the above-mentioned combination region that is subjected to the smoothing process in the second step. A third step of binarizing the density data of each pixel in each pixel row in the joining direction by binarization, and a first step including the binarization result of the third step A fourth step of joining the binary image and the second binary image together; A storage medium in which a program for causing a computer to execute is recorded.