JP5298068B2 - Identification data recognition apparatus and control program thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an identification data recognition device and a control program of the same capable of correctly recognizing identification data with high reliability without being affected by incident light even if light impinging on the identification data is reflected with high brightness to enter imaging means. <P>SOLUTION: If the result of decoding by line scanning satisfies recognition conditions, the result is confirmed as the result of recognition on a bar-code. If high brightness reflection data associated with high-brightness reflection on an article is contained in the result of decoding by line scanning, the recognition conditions are corrected. <P>COPYRIGHT: (C)2012,JPO&amp;INPIT

Description

  Embodiments described herein relate generally to an identification data recognition apparatus and a control program thereof.

  There is known an apparatus that irradiates an article with identification data such as a bar code and recognizes the identification data by receiving reflected light from the article with an imaging means.

Japanese Patent Laid-Open No. 3-108084

  Due to the influence of the intensity and angle of light hitting the identification data or the material on which the identification data is printed, the light hitting the identification data may be reflected with high brightness and enter the imaging means.

  In this case, there is a possibility that the image of the identification data cannot be accurately captured and the identification data is erroneously recognized.

  The object of the embodiment of the present invention is to ensure that the identification data can be accurately recognized without being affected even when the light hitting the identification data is reflected with high brightness and enters the imaging means. An excellent identification data recognition apparatus and a control program therefor are provided.

  An identification data recognition apparatus according to an embodiment of the present invention includes a light irradiating unit that irradiates light to an article with identification data, and an imaging unit that receives reflected light from the article and outputs a signal corresponding to the amount of received light. A binarizing unit that binarizes the output of the imaging unit, an extracting unit that extracts image data of the identification data candidate region from the binarized data by the binarizing unit, and the extracting unit extracts Decoding means for decoding image data, a confirmation means for confirming the decoding result as a recognition result for the identification data when the decoding result of the decoding means satisfies a recognition condition, and the article in the decoding result of the decoding means A determination unit that determines whether or not high-intensity reflection data based on high-intensity reflection from is included, and if the determination result of the determination unit is affirmative, the recognition condition is Comprising a positive correcting means.

The external view which shows the cash register of the shop in connection with one Embodiment. The figure which shows the structure of the principal part of the embodiment. The block diagram of the control circuit of the embodiment. The time chart for demonstrating the effect | action of the embodiment. The figure which shows the example of the image data of the barcode which is the reading object of the embodiment. The figure which shows the example in which high-intensity reflective data is contained in the image data of the barcode which is the reading target of the embodiment.

  DESCRIPTION OF SYMBOLS 1 ... Cashier work area, 2 ... Checkout counter, 3 ... Cash register, 10 ... Product registration device, 11 ... Bar code recognition device, 12 ... Keyboard, 13 ... Display for operator, 14 ... Display for customer, 15 ... Reading Windows, 16, 17 ... LED light source (light irradiation means), 20 ... settlement device, 30 ... merchandise (article), 31 ... bar code (identification data), 42 ... CCD sensor (imaging means), 50 ... CPU, 52 ... Microcomputer, 61 ... ROM, 62 ... RAM

  Hereinafter, an embodiment will be described with reference to the drawings. As an identification data recognition device, a barcode recognition device used for a checkout operation of a store such as a supermarket will be described as an example.

  FIG. 1 shows the appearance of a cash register in a store according to this embodiment. In this cash register, a merchandise registration apparatus 10 and a settlement apparatus 20 are installed so as to surround a work area 1 of a cashier who is a clerk in charge of checkout work.

  The merchandise registration apparatus 10 is placed on the checkout counter 2, and the settlement apparatus 20 is placed on the cash register 3 via the drawer 4.

  The checkout counter 2 is arranged along the customer's passage. The cash register 3 is arranged at a position downstream of the checkout counter 2 in the customer's passage and at a substantially right angle to the checkout counter 2.

  The payment apparatus 20 is, for example, a POS (Point Of Sales) terminal, and includes a keyboard 21, an operator display 22, a customer display 23, a receipt printer 24, and the like as devices necessary for payment.

  The product registration apparatus 10 includes a barcode recognition device 11, a keyboard 12, an operator display 13, a customer display 14 and the like as devices necessary for product registration. The bar code recognition device 11 is erected substantially at the center in the longitudinal direction of the checkout counter 2. The keyboard 12 and the operator display 13 are attached to the upper part of the barcode recognition device 11 with the work area 1 side facing. The customer display 14 is attached to the upper part of the barcode recognition device 11 with the side opposite to the work area 1 facing.

  The barcode recognition device 11 has a rectangular reading window 15 on the surface facing the cashier. At positions along the upper and lower edges of the reading window 15, there are light irradiating means for irradiating the product held in front of the reading window 15, for example, LED light sources 16, 17 using light emitting diodes. It is installed.

  The checkout counter 2 has a space for placing a shopping container 5 containing a product (article) 30 to be purchased by a customer and a product 30 registered by the barcode recognition device 11 at positions adjacent to the barcode recognition device 11. A space is provided for placing a shopping container 6 for storing the item.

  The cashier takes out the products 30 stored in the shopping container 5 one by one, and the surface of the barcode 31 which is identification data attached to the products 30 is placed in the reading window 15 of the barcode recognition device 11 as shown in FIG. Hold it over. Then, after the barcode recognition by the barcode recognition device 11 is completed, the cashier puts the product 30 into the shopping container 6. The above operation is repeated for every product 30 stored in the shopping container 5 for each product, and when completed, the settlement device 20 is operated to perform settlement.

  As shown in FIG. 2, the inner peripheral edge of the reading window 15 of the barcode recognition device 11 is surrounded by a frame member 41, and imaging means such as a CCD sensor 42 is arranged at a position facing the opening of the frame member 41. Yes. The CCD sensor 42 is mounted on a sensor control board 43, and the sensor control board 43 is mounted on a main control board 44 that controls the entire barcode recognition device 11.

  When the LED light sources 16 and 17 emit light, the product 30 is irradiated with the light, and the reflected light from the product 30 passes through the reading window 15 and reaches the CCD sensor 42. The CCD sensor 42 receives the reflected light from the product 30 and outputs an analog signal having a level corresponding to the amount of light received.

A control circuit mounted on the main control board 44 of the barcode recognition device 11 is shown in FIG.
A microcomputer 52, which is a control unit, is connected to the CPU 50 and the chip set 51. The microcomputer 52 includes a ROM 61 for storing programs, a RAM 62 for storing various data, an output port 63, a communication interface 64, a keyboard controller 65, and a display controller. 66, 67, the light source controller 68, and the sensor control board 43 are connected.

  A buzzer 70 is connected to the output port 63. The communication interface 64 performs data transmission / reception with the settlement apparatus 20 via a communication cable. The keyboard controller 65 controls the keyboard 12. The display controller 66 controls the operator display 13. The display controller 67 controls the customer display 14. The light source controller 68 controls the LED light sources 16 and 17. The sensor control board 43 controls the CCD sensor 42.

The microcomputer 52 has the following means (1) to (7) as main functions based on the control program in the ROM 61.
(1) Binarization means for binarizing the output of the CCD sensor 42. The binarized data is stored in the RAM 62.

  (2) Extraction means for extracting image data of a barcode candidate area (identification data candidate area) from the binarized data by the binarization means. As this extraction method, for example, a method disclosed in JP-A-9-62763 can be used.

  (3) Selection means for selecting one of a plurality of barcode candidate areas when the extraction means extracts image data of a plurality of barcode candidate areas.

  (3) Decoding means for decoding the image data extracted by the extraction means or selected by the selection means by repeating line scanning.

  (4) When the decoding result of the decoding means satisfies the recognition condition, specifically, when the decoding result of the decoding means matches over the line scan of the set number of times X, the decoding result is used as the barcode recognition result. Confirming means to confirm.

  (5) Determination means for determining whether or not the decoding result of the decoding means includes high-intensity reflection data based on high-intensity reflection from the product 30. Specifically, if a black image pattern of each bar of the barcode includes a chip (irregular shape white image pattern), the chipped portion is captured as high-intensity reflection data.

  (6) Correction means for correcting the set number of times X, which is the recognition condition, in an increasing direction when the determination result of the determination means is affirmative.

  (7) When the decoding result of the decoding means does not coincide with the set number of line scans and the line scanning by the decoding means deviates from the image data area selected by the selection means, the selection means separates Control means for selecting image data of one identification data candidate area.

Next, the operation will be described with reference to the flowchart of FIG.
When the light from the LED light sources 16, 17 strikes the barcode 31 of the product 30 and is reflected, the reflected light enters the CCD sensor 42 through the reading window 15. At this time, the CCD sensor 42 outputs an analog signal having a level corresponding to the amount of received light.

The output signal of the CCD sensor 42 is binarized, and the binarized data is stored in the RAM 62. Then, the image data of the barcode candidate area (identification data candidate area) is extracted from the binarized data in the RAM 62 (step 101). If the image data of the barcode candidate area is not extracted (NO in step 102), the process ends as it is.
Examples of image data to be extracted are shown in FIGS.

  When one image data is extracted as a barcode candidate area (YES in step 102), the image data is selected as it is (step 103). If there are a plurality of extracted image data (YES in step 102), one of the image data is selected (step 103).

A process of measuring the bar length D is performed on the extracted and selected barcode image data (step 104). Further, the number N of line scans L11, L12... L16 that can be executed in the measured length D is obtained, and the mutual interval S between the line scans L11, L12. Step 105). S = L / N
Line scanning is also referred to as decoding scanning. The direction of line scanning is referred to as main scanning, and the direction in which this line scanning proceeds is referred to as sub-scanning. If the x coordinate of the first pixel of the first line scan L11 is x11 and the y coordinate is y11, the x and y coordinates (x12, y12) of the first pixel of the second line scan L12 are the first pixel of the line scan L11. It can be obtained as a coordinate value (x11, y12 + S) obtained by adding the calculated mutual interval S as an offset value of the y coordinate based on the x, y coordinate (x11, y11). The x and y coordinates of the first pixel of the subsequent line scan can be similarly obtained with reference to the immediately preceding line scan. The nth pixel from the head on each line scan following the x, y coordinates (x11, y11) of the head pixel of the line scan L11 can be obtained by rotating the coordinate value (x11 + n, y11).

  The extracted and selected barcode image data is decoded by line scanning (step 106). That is, the first line scan L11 is performed on the barcode image data in the direction orthogonal to each bar, and thereby the barcode is decoded.

  If the decoding result is appropriate (YES in step 107), it is determined whether or not the decoding result includes high-intensity reflection data based on the high-intensity reflection from the product 30 (step 108). If the high-intensity reflection data is not included as shown in FIG. 5 (NO in step 108), the set number X of recognition conditions such as “3” is held as it is (step 110). Then, it is determined whether or not the decoding result is consistent over the line scanning for the set number of times X (step 112). In this case, since it is still the first line scan, the determination result is negative (NO in step 112), and the next line scan L12 is designated (step 114).

  Based on this designation, decoding by the next line scan L12 is executed (step 106). If the decoding result is appropriate (YES in step 107), whether or not the high luminance reflection data is included in the decoding result. Is again determined (step 108). If high brightness reflection data is not included (NO in step 108), the set number X is held at the same value X (step 110). Then, it is determined whether or not the decoding result is consistent over the line scanning for the set number of times X (step 112). In this case, since it is still the second line scan, the determination result is negative (NO in step 112), and the next line scan L13 is designated (step 114).

  Based on this designation, decoding by the next line scan L13 is executed (step 106), and if the decoding result is appropriate (YES in step 107), whether or not the high luminance reflection data is included in the decoding result. Is again determined (step 108). If high brightness reflection data is not included (NO in step 108), the set number X is held at the same value X (step 110). Then, it is determined whether or not the decoding result is consistent over the line scanning for the set number of times X (step 112). If a determination result of X coincidence is obtained in the third line scanning (YES in step 112), it is determined that decoding is established, and the decoding result is determined as a recognition result for the barcode 31 (step 113). This completes barcode recognition.

  If the decoding result by the line scan L13 is not appropriate due to some cause such as noise (NO in step 107), the next line scan L14 is designated (step 114). Based on this designation, decoding by the next line scan L14 is executed (step 106). If the decoding result is appropriate (YES in step 107), whether or not the high luminance reflection data is included in the decoding result. Is again determined (step 108). If high brightness reflection data is not included (NO in step 108), the set number X is held at the same value X (step 110). Then, it is determined whether or not the decoding result is consistent over the line scanning for the set number of times X (step 112). If a determination result of X coincidence is obtained in the fourth line scan (YES in step 112), it is determined that decoding is established, and the decoding result is determined as a barcode recognition result (step 113). This completes barcode recognition.

  If all the decoding results for the line scans L13 to L16 are not appropriate, or if the decoding results do not coincide over the set number of line scans even after the final line scan L16 is completed, Therefore, the line scan specified in (1) deviates from the area of the barcode image data (YES in step 115). In this case, if there is a plurality of image data of the extracted barcode candidate area, another image data different from the previous recognition target is selected as a new recognition target (YES in step 102, step 103). Then, the barcode recognition process similar to the above is executed on the selected image data.

  If there is one image data of the extracted barcode candidate area (NO in step 102), the process ends without completing barcode recognition.

  On the other hand, since each bar of the barcode 31 is a black image pattern, it should originally have little reflected light. However, depending on the material of the printing surface of the barcode 31 (such as glossy one), high-brightness reflection occurs regardless of the black image pattern of each bar and the white image pattern between the bars, as shown in FIG. As described above, a part of the black image pattern of each bar is missing (irregularly shaped white image pattern P).

  When the barcode image data is decoded by each line scan, an irregularly shaped white image pattern P existing in a part of the black image pattern of each bar is detected as high-intensity reflection data (step). 108 YES). Accompanying this detection, the set number X (for example, “3”) of the recognition condition is corrected in an increasing direction by a predetermined number α (for example, “2”) (step 111).

  When the decoded result matches over the number of line scans corresponding to the set number of times X (= “5”) after correction (YES in step 112), it is determined that decoding is established, and the decoded result is determined as a recognition result for the barcode 31. (Step 113). This completes barcode recognition.

  As described above, when the high-intensity reflection data is included in the barcode image data, the recognition condition is tightened by correcting the set number X in the increasing direction, so that the barcode 31 portion of the product 30 can be used. Even when high-brightness reflection occurs and the reflected light enters the CCD sensor 42, the barcode 31 can be accurately recognized without being affected by the reflection. This greatly improves the reliability of barcode recognition.

In the above-described embodiment, the case where the identification data is a barcode has been described as an example. However, not only the barcode but also other identification data can be similarly recognized. In addition, “3” is used as the set number X as a recognition condition and “2” is used as the predetermined number α for correction. The set number X and the predetermined number α are the barcode size, the resolution of the CCD sensor 42, and the like. It may be selected appropriately according to the situation.
In addition, this invention is not limited to each said embodiment, A various deformation | transformation implementation is possible in the range which does not change a summary.

Claims (6)

A light irradiating means for irradiating the article with the identification data;
Imaging means for receiving reflected light from the article and outputting a signal corresponding to the amount of light received;
Binarization means for binarizing the output of the imaging means;
Extracting means for extracting image data of the identification data candidate area from the binarized data by the binarizing means;
Decoding means for decoding the image data extracted by the extracting means;
When the decoding result of the decoding means satisfies the recognition condition, a confirmation means for determining the decoding result as a recognition result for the identification data;
A determination unit that determines whether or not the decoding result of the decoding unit includes high-intensity reflection data based on high-intensity reflection from the article;
A correction unit that corrects the recognition condition when the determination result of the determination unit is affirmative;
An identification data recognition apparatus comprising: The identification data is a barcode,
The decoding means decodes the image data extracted by the extracting means by repeating line scanning,
The determination means determines the decoding result as a recognition result for the barcode when the decoding result of the decoding means coincides over a set number of line scans,
The correction means corrects the set number of times in an increasing direction when the determination result of the determination means is affirmative;
The identification data recognition apparatus according to claim 1. Selection means for selecting one of the plurality of identification data candidate areas when the extraction means extracts image data;
The identification data recognition apparatus according to claim 2, further comprising: The decoding means decodes the image data extracted by the extracting means or selected by the selecting means by repeating line scanning,
The identification data recognition apparatus according to claim 3. When the line scanning by the decoding means deviates from the area of the image data selected by the selection means while the decoding result of the decoding means does not coincide over the set number of line scans, another one is selected by the selection means. Control means for selecting the image data of the identification data candidate area;
The identification data recognition apparatus according to claim 4, further comprising: In an identification data recognition device comprising a light irradiation means for irradiating an article with identification data, an imaging means for receiving reflected light from the article and outputting a signal corresponding to the amount of received light, and a computer,
In the computer,
A function of binarizing the output of the imaging means;
A function of extracting the image data of the identification data candidate area from the binarized data by the binarization;
A function of decoding the extracted image data;
When this decoding result satisfies a recognition condition, a function of determining the decoding result as a recognition result for the identification data;
A function of determining whether or not high-intensity reflection data based on high-intensity reflection from the article is included in the decoding result;
A function of correcting the recognition condition when the determination result is affirmative;
A control program for an identification data recognition apparatus, characterized in that

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