Identification code detection device and identification code detection method

Abstract

Provided is an identification code detection device that can accurately detect code information of a plurality of identification codes in a simple manner. 【Solution means】The identification code detection device 10 of the present invention includes an imaging unit 11 that acquires image information including an image of an identification code 4, a distance measurement unit 13 that measures the distance from the imaging unit for a plurality of identification codes 4 extracted from the image information, a distance map generation unit 14 that generates a distance map showing the relationship between the subject distance and the in-focus range using the measurement result of the distance of the identification code 4, and an identification code detection unit 15 that detects the code information of the identification code 4 using the image information acquired according to the in-focus range in the distance map.

Description

Technical Field

[0001] The present invention relates to an identification code detection device that detects an identification code assigned to a package.

Background Art

[0002] As a technology for managing packages in a warehouse, a method of managing the presence or absence and installation location of packages in the warehouse by reading an identification code assigned to the package has been implemented. For example, in Patent Document 1, a scanner reads an identification display for identifying a product to be managed and an identification display for identifying the location where the product is placed, compares the actual number data of the read product with the product data stored in a database, and a system for rewriting the product inventory record in the database has been proposed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When reading an identification code for identifying a product to be managed in a warehouse or the like with a scanner, it is necessary to read the identification codes of a large number of products to be managed during inspection at the time of incoming and outgoing shipments, and the burden of manual labor for reading the identification codes is large. Recently, a technology for simultaneously reading multiple identification codes with a high-quality camera mounted on a mobile terminal such as a smartphone has been put into practical use. However, when simultaneously photographing multiple identification codes with the camera of a mobile terminal, if the number of identification codes to be photographed is large, it is necessary to secure a certain distance between the camera and the package, so the photographing resolution deteriorates according to the distance between the camera and the package, and all the identification codes may not be accurately detected.

[0005] The present invention has been made to solve the above problems, and an object thereof is to provide an identification code detection device capable of accurately detecting code information of a plurality of identification codes in a simple manner.

Means for Solving the Problems

[0006] In order to solve the above-described problems, the identification code detection device of the present invention includes an imaging unit that acquires image information including an image of an identification code, and in first image information including a plurality of identification codes acquired by the imaging unit, an area of the identification code is extracted, and for each of the extracted areas of the identification code, a distance measurement unit that measures a distance from the first imaging unit, a distance map generation unit that generates a distance map showing the relationship between the subject distance and the focusing range using the measurement result of the distance measurement unit, and an identification code detection unit that detects the code information of the identification code using second image information acquired by the imaging unit according to the focusing range in the distance map. The imaging unit acquires the second image information including at least one of the identification codes in the focusing range including the distance of the area of the identification code according to the focus drive position determined based on the focusing range and the distance of the area of the identification code, and the identification code detection unit detects the code information of the identification code in the second image information.

[0007] Further, the distance map generation unit may generate the distance map in which the focusing range is set so that the distances of the areas of the plurality of identification codes are included in at least one of the focusing ranges, and the imaging unit may acquire the second image information including the plurality of identification codes in the focusing range set in the distance map.

[0008] In order to solve the problems as described above, the identification code detection method of the present invention is an identification code detection method executed in an identification code detection device including an imaging unit that acquires image information including an image of an identification code, a distance measurement unit that measures the distance from the imaging unit to the area of the identification code in the image information, a distance map generation unit that generates a distance map showing the relationship between the subject distance and the in-focus range using the measurement result of the distance measurement unit, and an identification code detection unit that detects the code information of the identification code using second image information acquired by the imaging unit according to the in-focus range in the distance map. The method includes: a step in which the imaging unit acquires first image information including an image of the identification code; a step in which the distance measurement unit extracts the area of the identification code from the first image information including a plurality of identification codes acquired by the imaging unit, and measures the distance from the first imaging unit for each of the extracted areas of the identification code; a step in which the distance map generation unit generates a distance map showing the relationship between the subject distance and the in-focus range using the measurement result of the distance measurement unit; and a step in which the identification code detection unit detects the code information of the identification code using second image information acquired by the imaging unit according to the in-focus range in the distance map. The imaging unit acquires second image information including at least one of the identification codes in the in-focus range including the distance of the area of the identification code according to the focus drive position determined based on the in-focus range and the distance of the area of the identification code, and the identification code detection unit detects the code information of the identification code in the second image information.

[0009] Further, the distance map generation unit may generate the distance map in which the in-focus range is set so that the distances of the areas of a plurality of the identification codes are included in at least one of the in-focus ranges, and the imaging unit may acquire second image information including a plurality of the identification codes in the in-focus range set in the distance map.

Advantages of the Invention

[0010] According to the present invention, it is possible to provide an identification code detection device that can accurately detect code information of a plurality of identification codes in a simple manner.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention can be implemented in various embodiments and is not limited to the embodiments of the invention described below.

[0013] <Configuration of the Baggage Management System> FIG. 1 is an example of a system configuration including an identification code detection device according to an embodiment of the present invention. The identification code detection system 1 in FIG. 1 acquires a baggage image in a state where a baggage 2 with an identification code 4 attached is placed on a pallet 3, and uses the acquired baggage image to detect code information of the identification code attached to the baggage 2. The identification code detection system 1 includes an identification code detection device 10 and an identification code management server 20 that manages the code information of the identification code detected by the identification code detection device 10.

[0014] Recently, a technology for simultaneously reading multiple identification codes with a high-quality camera mounted on a mobile terminal such as a smartphone has been put into practical use. However, when simultaneously photographing multiple identification codes with the camera of a mobile terminal, if the number of identification codes to be photographed is large, it is necessary to secure a certain distance between the camera and the luggage. Therefore, depending on the distance between the camera of the mobile terminal and the luggage, the shooting resolution may deteriorate and it may not be possible to accurately detect all the identification codes.

[0015] In this embodiment, when detecting the code information of a plurality of identification codes 4 attached to the luggage 2 placed at different positions, the imaging unit 11 acquires image information (first image information) including the plurality of identification codes 4, extracts the identification codes 4, measures the distance between the extracted identification codes and the imaging unit 11, generates a distance map showing the relationship between the subject distance and the focusing range using the measured distance, determines the focus drive position of the imaging unit 11 according to the focusing range in the generated distance map, and detects the code information of the identification code 4 using the image information (second image information) of the identification code 4 acquired at the determined focus drive position.

[0016] By determining the focus drive position of the imaging unit 11 according to the focusing range in the distance map created according to the distance between the imaging unit 11 and the identification code 4, it is possible to acquire images of a plurality of identification codes in a focused state included in one focusing range. Therefore, it is possible to detect the code information of a plurality of identification codes 4 at different positions with fewer focus drive operations without performing a focus drive operation for each individual identification code.

[0017] <Configuration of the Identification Code Detection Device> FIG. 2 is an example of a functional block of an identification code detection device according to an embodiment of the present invention.

[0018] The identification code detection device 10 includes an imaging unit 11 for acquiring a captured image including the identification code 4, a distance sensor unit 12 for measuring the distance to the identification code 4, a central processing unit that measures the distance to the identification code 4 using the distance sensor unit 12 to generate a distance map, and detects the code information of the identification code 4 using the generated distance map, a storage unit 16 for storing various information, etc., an input unit 17 for the photographer to input information, a display unit 18 for displaying the detection status of the identification code 4, and a wireless unit 19 for transmitting information to the identification code management server 20.

[0019] The central processing unit functions as a distance measurement unit 13 that measures the distance to the identification code 4 using the distance sensor unit 12, a distance map generation unit 14 that generates a distance map showing the relationship between the subject distance and the focusing range using the measurement result of the distance measurement unit 13, and an identification code detection unit 15 that detects the code information of the identification code 4 using the image information acquired by the imaging unit 11 according to the focusing range in the generated distance map.

[0020] The identification code detection unit 15 determines the focus drive position of the imaging unit 11 according to the focusing range in the distance map showing the relationship between the subject distance and the focusing range, which is generated using the distance measured by the distance measurement unit 13, and detects the code information of the identification code 4 using the image information of the identification code 4 acquired by the imaging unit 11 at the determined focus drive position.

[0021] As a result, it is possible to acquire the images of the plurality of identification codes 4 included in one focusing range in a focused state. Therefore, without performing a focus drive operation for each individual identification code 4, it is possible to detect the code information of the plurality of identification codes 4 at different distances with fewer focus drive operations.

[0022] The memory unit 16 stores the measured distance information of the identification code 4 and the distance map generated using the measured distance information. The identification code detection unit 15 determines the focus drive position of the imaging unit 11 according to the in-focus range in the distance map stored in the memory unit 16, and can detect the code information of the identification code 4 using the image information of the identification code acquired by the imaging unit 11 at the determined focus drive position.

[0023] As the imaging unit 11, a general-purpose RGB camera can be used. As the identification code detection device 10 equipped with the imaging unit 11, for example, a digital camera equipped with an RGB camera, a smartphone, or the like can be used. As the distance sensor unit 12, a general-purpose distance measuring sensor such as a TOF (Time of Flight) sensor or a LiDAR sensor can be used.

[0024] The identification code detection device 10 can be configured by a computer equipped with a CPU, a memory, and an interface for connecting to external devices.

[0025] <Measurement of the Distance of the Identification Code> FIG. 3 is a diagram for explaining the measurement of the distance of the identification code in the embodiment of the present invention. In the example of FIG. 3, a plurality of packages 2 with the identification code 4 are placed on the pallet 3.

[0026] The identification code detection device 10 extracts the region of the identification code 4 from the image information including a plurality of identification codes 4 acquired by the imaging unit 11, and measures the distance (L1-L5) from the imaging unit 11 for each of the extracted regions of the identification code 4.

[0027] In the example of FIG. 3, image information including a plurality of images of the identification code 4 assigned to the package 2 is acquired, and the area of the identification code 4 is detected in the acquired image information. The extraction of the area of this identification code 4 is sufficient if the position where the identification code exists can be specified on the image even if the identification code itself cannot be read. The detection of the identification code area can be realized, for example, by detecting the frequency component of the identification code. The area of the identification code may be estimated using the result of learning the identification code 4.

[0028] <Generation of distance map> In the present embodiment, when detecting the code information of a plurality of identification codes 4 assigned to packages 2 placed at different distances, the distance between the imaging unit 11 and the identification code 4 is measured, and a distance map showing the relationship between the subject distance and the focusing range is generated using the measured distance. FIGS. 4 and 5 are diagrams for explaining examples of distance maps in the embodiments of the present invention.

[0029] The distance maps in FIGS. 4 and 5 are distance maps showing the relationship between the subject distance and the focusing range. The imaging unit 11 has a focusing range (depth of field) centered on the focusing position, and the imaging unit 11 has a focusing range (depth of field) corresponding to the focus drive position.

[0030] FIG. 4 is an example of a distance map having five focusing ranges (F1 - F5). The focus drive position of the imaging unit 11 is determined based on the focusing range in the distance map and the distance to the identification code 4.

[0031] In FIG. 4, by setting the focus drive position of the imaging unit 11 at the focus positions D1 - D3 of the focusing ranges F3 - F5 that include the distances L1 - L5 of the identification code 4 among the five focusing ranges (F1 - F5), the identification code 4 can be detected.

[0032] FIG. 5 is an example of a distance map in which two focusing ranges (F1, F2) are set according to the distances L1 - L5 of the identification code 4. The focus drive position of the imaging unit 11 is determined based on the focusing range in the distance map and the distance to the identification code 4.

[0033] In FIG. 5, by setting the focus drive position of the imaging unit 11 to the focus positions D1 and D2 of the in-focus ranges F1 and F2 including the distances L1 - L5, the identification code 4 can be detected.

[0034] <Detection of Identification Code> The identification code detection device 10 determines the focus drive position of the imaging unit 11 according to the in-focus range in the generated distance map, and detects the code information of the identification code 4 using the image information of the identification code 4 acquired at the determined focus drive position.

[0035] In FIG. 4, the distance L3 of the identification code 4 is included in F3, the distance L5 of the identification code 4 is included in F4, and the distances L1, L2, and L4 of the identification code 4 are included in F5. Therefore, by adjusting the focus drive position of the imaging unit 11 to D1, D2, and D3, the identification code 4 arranged at the distances L1 - L5 can be detected.

[0036] Here, since the distances L1, L2, and L4 of the identification code 4 are included in the in-focus range F5, by adjusting the focus drive position of the imaging unit 11 to F5, three identification codes 4 can be detected.

[0037] In FIG. 5, the distances L3 and L5 of the identification code 4 are included in F1, and the distances L1, L2, and L4 of the identification code 4 are included in F2. Therefore, by adjusting the focus drive position of the imaging unit 11 to D1 and D2, the identification code 4 arranged at the distances L1 - L5 can be detected.

[0038] Here, since the distances L3 and L5 of the identification code 4 are included in the in-focus range F1, and the distances L1, L2, and L4 of the identification code 4 are included in the in-focus range F2, compared with the distance map in FIG. 4, five identification codes 4 can be detected with fewer focus drive positions.

[0039] In this way, by determining the focus drive position of the imaging unit 11 according to the in-focus range in the distance map created according to the distance between the imaging unit 11 and the identification code 4, it is possible to obtain images of a plurality of identification codes 4 in a focused state included in one in-focus range. Therefore, it is possible to detect the code information of a plurality of identification codes 4 at different distances with fewer focus drive operations without performing a focus drive operation for each individual identification code 4.

[0040] <Operation Flow of Identification Code Detection Device> Using FIG. 6, the operation of the identification code detection method executed in the identification code detection device 10 will be described. FIG. 6 is an example of the operation flow of the identification code detection method according to an embodiment of the present invention.

[0041] Each step of the identification code detection method is executed in an identification code detection device 10 including an imaging unit 11 that acquires image information including an image of an identification code, a distance measurement unit 13 that measures the distance from the imaging unit to the area of the identification code in the image information, a distance map generation unit 14 that generates a distance map showing the relationship between the subject distance and the in-focus range using the measurement result of the distance measurement unit, and an identification code detection unit 15 that detects the code information of the identification code using the image information acquired by the imaging unit 11 according to the in-focus range in the distance map.

[0042] The imaging unit 11 of the identification code detection device 10 acquires image information including an image of an identification code (S1-1).

[0043] The distance measurement unit 13 of the identification code detection device 10 extracts the area of the identification code from the image information including a plurality of identification codes acquired by the imaging unit 11 (S1-2).

[0044] The distance measurement unit 13 of the identification code detection device 10 measures the distance from the imaging unit 11 for each of the extracted areas of the identification code using the distance sensor unit 12 (S1-3).

[0045] The distance map generation unit 14 of the identification code detection device 10 generates a distance map showing the relationship between the subject distance and the in-focus range using the measurement result of the distance measurement unit 13 (S1-4).

[0046] The identification code detection unit 15 of the identification code detection device 10 determines the focus drive position based on the in-focus range of the distance map and the distance of the area of the identification code (S1-5).

[0047] The imaging unit 11 of the identification code detection device 10 acquires image information including the identification code in the in-focus range including the distance of the area of the identification code according to the determined focus drive position (S1-6).

[0048] The identification code detection unit 15 of the identification code detection device 10 detects the code information of the identification code using the image information acquired by the imaging unit 11 according to the in-focus range in the distance map (S1-7).

[0049] The focus drive and the detection of the identification code information are repeated until the identification code is detected at all the determined focus drive positions (S1-8).

[0050] In the present embodiment, when detecting the code information of a plurality of identification codes 4 attached to the packages 2 placed at different distances, the imaging unit 11 acquires image information (first image information) including the plurality of identification codes 4, extracts the identification codes 4, measures the distance between the imaging unit 11 and the extracted identification codes, generates a distance map showing the relationship between the subject distance and the in-focus range using the measured distance, determines the focus drive position of the imaging unit 11 according to the in-focus range in the generated distance map, and detects the code information of the identification code 4 using the image information (second image information) of the identification code 4 acquired at the determined focus drive position.

[0051] According to this embodiment, by determining the focus drive position of the imaging unit 11 according to the in-focus range in the distance map created according to the distance between the imaging unit 11 and the identification code 4, it is possible to acquire images of a plurality of identification codes in a focused state included in one in-focus range. Therefore, without performing a focus drive operation for each individual identification code, it becomes possible to detect the code information of a plurality of identification codes 4 at positions with different distances with fewer focus drive operations.

[0052] According to this embodiment, it becomes possible to provide an identification code detection device that can accurately detect the code information of a plurality of identification codes in a simple manner.

Explanation of Reference Numerals

[0053] 1... Identification code detection system, 2... Luggage, 3... Pallet, 4... Identification code, 10... Identification code detection device, 11... Imaging unit, 12... Distance sensor unit, 13... Distance measurement unit, 14... Distance map generation unit, 15... Identification code detection unit, 16... Storage unit, 17... Input unit, 18... Display unit, 19... Wireless unit, 20... Identification code management server.

Claims

1. an imaging unit for acquiring image information including an image of an identification code; a distance measurement unit that extracts areas of the identification codes from first image information including a plurality of identification codes acquired by the imaging unit, and measures a distance from the imaging unit to each of the extracted areas of the identification codes; a distance map generating unit that generates a distance map indicating a relationship between a subject distance and a focusing range using a measurement result of the distance measuring unit; an identification code detection unit that detects code information of the identification code by using second image information acquired by the imaging unit according to the focusing range in the distance map; Equipped with The imaging unit includes: acquiring the second image information including at least one of the identification codes in the focusing range that includes the distance of the identification code area, in accordance with a focus driving position determined based on the distance between the focusing range and the identification code area; The identification code detection unit Detecting code information of the identification code in the second image information. Identification code detection device.

2. The distance map generation unit generating the distance map in which the focus range is set so that at least one of the focus ranges includes the distances of a plurality of the identification code regions; The imaging unit includes: The second image information including the plurality of identification codes is acquired within the focusing range set in the distance map.

2. The identification code detection device according to claim 1.

3. an identification code detection method executed in an identification code detection device including an imaging unit that acquires image information including an image of an identification code; a distance measurement unit that measures a distance from the imaging unit to an area of ​​the identification code in the image information; a distance map generation unit that generates a distance map indicating a relationship between a subject distance and a focusing range using a measurement result of the distance measurement unit; and an identification code detection unit that detects code information of the identification code using the image information acquired by the imaging unit in accordance with the focusing range in the distance map, acquiring, by the imaging unit, first image information including an image of the identification code; a step of the distance measurement unit extracting an area of ​​the identification code from first image information including a plurality of identification codes acquired by the imaging unit, and measuring a distance from the imaging unit to each of the extracted areas of the identification code; a step of generating a distance map indicating a relationship between a subject distance and a focusing range by the distance map generating unit using a measurement result of the distance measuring unit; the identification code detection unit detects code information of the identification code by using second image information acquired by the imaging unit in accordance with the focusing range in the distance map; having The imaging unit includes: acquiring the second image information including at least one of the identification codes in the focusing range that includes the distance of the identification code area, in accordance with a focus driving position determined based on the distance between the focusing range and the identification code area; The identification code detection unit Detecting code information of the identification code in the second image information. Identification code detection method.

4. The distance map generation unit generating the distance map in which the focus range is set so that at least one of the focus ranges includes the distances of a plurality of the identification code regions; The imaging unit includes: The second image information including the plurality of identification codes is acquired within the focusing range set in the distance map.

4. The method of claim 3.

Images