JP4470860B2 - Information code reader - Google Patents

Description

The present invention relates to an information code reader for reading a one-dimensional information code such as a barcode and a two-dimensional information code such as a QR code (registered trademark).

In an information code reading device, an image of a one-dimensional information code such as a bar code or a two-dimensional information code such as a QR code is acquired by an image sensor, and the information is decoded and read. In recent years, the accuracy of reading has been improved by increasing the number of pixels of an image sensor such as an image sensor and increasing the resolution of the image, but on the other hand, the amount of information to be decoded has increased and the decoding processing time has become longer. Has arisen. Furthermore, since an image with a large number of pixels is captured in the memory, the capture time is also greatly increased.

In order to cope with such a problem, Patent Document 1 discloses a two-dimensional code reading apparatus that captures a two-dimensional code image at a high resolution and stores it in a memory, reduces the image, and extracts a two-dimensional code from the reduced image. Proposed.
JP 2000-259761 A

However, since the two-dimensional code reader of Patent Document 1 captures images with high resolution and stores them in a memory, there is a problem that it takes time to capture images. In other words, the size of the cells that make up a two-dimensional code varies, and a two-dimensional code that uses fine-pitch cells may not be read unless imaged at a high resolution. For a two-dimensional code consisting of the above cells, imaging is performed at an unnecessarily high resolution, which takes time for imaging and decoding, and increases the reading time.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an information code reader capable of reading an information code reliably in a short time.

In order to achieve the above object, the invention of claim 1 is an information code reader 10 for reading an information code:
A low-resolution image acquisition unit (S12) that acquires an image of an information code at a low resolution in a substantially same imaging region, and a high resolution that acquires an image of the information code at a higher resolution than the low-resolution image acquisition unit Image acquisition means (S30);
Determining means (S18) for determining whether or not the information code can be read from the low resolution image;
When it is determined by the determination means that it can be read (S18: Yes), the information of the low resolution information code is decoded, and when it is determined that it is not possible (S18: No), the high resolution information. Decoding means (S30, S32) for decoding from a code image ;
When decoding is performed from the low-resolution information code image and decoding fails (S22: Yes), the region ER where decoding has failed is identified (S24),
The decoding that has already been completed with the low resolution image is used, and the region ER where the decoding has failed is decoded from the high resolution image to complement the decoding failure performed from the low resolution image (S28). This is a technical feature.

In claim 1, an information code image is acquired at a low resolution (S12), and it is determined whether or not the information code can be read from the low resolution image (S18). S18: Yes), decoding is performed from the low resolution information code image (S20). Since decoding is performed with an image having a low resolution, an information code can be read in a shorter time than when a high resolution image is acquired and decoded. On the other hand, when it is determined that decoding from a low-resolution information code image is impossible (S18: No), decoding is performed from a high-resolution information code image (S32). For this reason, an information code can be read reliably. In particular, in order to determine whether or not decoding with a low resolution image is possible in advance compared to decoding with a high resolution image when decoding actually fails with a low resolution image, The reading time of the information code can be shortened. Furthermore, when decoding fails with an image of a low resolution information code (S22: Yes), the region ER where decoding has failed is identified (S24). Then, the decoding that has already been completed for the low resolution image is used, and the decoding from the high resolution image is performed in the area ER, and the decoding failure performed from the low resolution image is complemented (S28). For this reason, even when decoding from an image with a low resolution information code fails and decoding from an image with a high resolution information code is performed, the decoding that has already been completed with the low resolution image is used. Since only the minimum area ER that failed to be decoded is decoded, it does not take time for decoding, and the information code can be read in a short time.

In claim 2, the area E1 where the information code exists is detected from the low resolution image (S14). Then, when decoding from an image of a high-resolution information code, the area E2 where the detected information code exists is decoded (S32). For this reason, for example, decoding from a low resolution information code image is impossible, and even when decoding from a high resolution information code image, only the minimum area E2 where the information code exists is decoded. Therefore, decoding does not take time, and the information code can be read in a short time.

According to the third aspect of the present invention, whether or not the information code can be read from the low resolution image is determined by checking whether at least one of the minimum units of the light and dark C constituting the information code in the low resolution image is equal to or more than a preset number of pixels. (S18). For this reason, it is possible to determine whether or not the information code can be read without trying to decode the image with a low resolution. As a result, it is possible to shorten the information code reading time compared to decoding with a high resolution image when decoding is actually performed with a low resolution image and decoding fails.

According to the fifth aspect, when it is determined that the information code cannot be read in the low resolution image (S18: No), the information code image is acquired at the high resolution (S30). That is, when an information code image is acquired at a low resolution and it is determined that the information code can be read from the low resolution image, the information code image is decoded from the low resolution image, and a high resolution image is obtained. Since it is not acquired, the information code can be read in a short time.

In claim 6, whether the information code is a one-dimensional code or a two-dimensional code is identified (S 29), and when the information code is identified as a one-dimensional code (S 29: Yes), the information code is displayed with high resolution only in the horizontal direction. An image is acquired (S31), and only when it is identified as a two-dimensional code (S29: No), an image of the information code is acquired with high resolution in the horizontal and vertical directions (S30). That is, for a one-dimensional code that does not require high resolution in the vertical direction, an image is acquired with a high resolution only in the horizontal direction, so that the one-dimensional code can be read in a short time.

[First embodiment]
Hereinafter, a first embodiment of an information code reader according to the present invention will be described with reference to the drawings. First, a configuration outline of the information code reading apparatus 10 according to the present embodiment will be described with reference to FIGS. 1 and 2.
As shown in FIG. 1, the information code reader 10 is mainly accommodated in a vertically long, substantially rectangular box-shaped housing 11, a circuit portion 20 accommodated in the housing 11, and the housing 11. And a battery 49 for supplying driving power to the circuit unit 20.

The housing 11 is a molded part made of synthetic resin such as ABS resin, for example, and is provided with a reading port 11a having a “neck bend shape” at one end thereof so as to tilt forward toward the back surface of the housing 11. The reading port 11a is an opening through which incident light incident on a light receiving sensor 23 of the circuit unit 20 described later can be introduced. On the other hand, an unillustrated battery box capable of accommodating the battery 49 is formed on the other end side of the housing 11. In addition, an opening to which the liquid crystal display 46 can be attached is formed on the front surface side of the housing 11 so that the user of the information code reading device 10 can visually grasp the display contents displayed on the liquid crystal display 46. It is composed.

The circuit unit 20 is configured by various electronic components 18 and the like mounted on the printed wiring boards 15 and 16 housed in the housing 11. That is, the circuit unit 20 mainly includes an optical system such as an illumination light source 21, a light receiving sensor 23, and an imaging lens 27, and a microcomputer such as a memory 35, a control circuit 40, an operation switch 42, and a liquid crystal display 46 (hereinafter, “ And a power supply system such as a power switch 41 and a battery 49. These are mounted on the printed wiring boards 15 and 16 or are housed in the housing 11.

Here, the configuration of the circuit unit 20 will be described later with reference to FIG. As shown in FIG. 2, the optical system constituting the circuit unit 20 includes an illumination light source 21, a light receiving sensor 23, a marker light source 25, an imaging lens 27, and the like. Although the illumination light source 21 is not described in FIG. 1, it functions as an illumination light source capable of emitting illumination light. For example, a red LED and a diffusing lens, a condensing lens, and the like provided on the emission side of the LED are provided. It is composed of In the present embodiment, illumination light sources 21 are provided on both sides of the light receiving sensor 23, and configured to be able to irradiate the illumination light Lf toward the reading object R through the reading port 11 a of the housing 11.

In the present embodiment, a red LED is used, but illumination of a two-dimensional barcode reader (optical information reader) that can read the two-dimensional code Q with various emission colors such as blue and white. You may match with the luminescent color of the light Lf. Thereby, the illumination light Lf can be irradiated from the illumination light source 21 in a state close to the light emission state of the illumination light of the two-dimensional barcode reader.

The light receiving sensor 23 is configured to receive the reflected light Lr irradiated and reflected on the reading object R or the two-dimensional code Q. For example, the light receiving sensor 23 is a solid-state image pickup device such as a C-MOS or CCD. This corresponds to an area sensor arranged two-dimensionally in m rows and n columns, and has 640 × 480 pixels. The light receiving sensor 23a of the light receiving sensor 23 is configured to be externally visible from the outside of the housing 11 through the reading port 11a. The light receiving sensor 23 receives incident light incident through the imaging lens 27. It is mounted on the printed wiring board 15 so that it can receive light at 23a.

The marker light source 25 functions as a marker light source capable of emitting marker light Mf for notifying the user of the information code reading device 10 of an appropriate reading position. For example, the marker light source 25 is provided on the laser diode and on the emission side of the laser diode. It comprises a diffusing lens, a condensing lens, a slit disk that can form a pattern such as a center mark MX and a corner mark ML by marker light Mf, an imaging lens, and a diaphragm.

The imaging lens 27 can function as an imaging optical system capable of condensing incident light incident from the outside via the housing 11 and forming an image on the light receiving sensor 23a of the light receiving sensor 23. For example, the lens barrel And a plurality of condensing lenses housed in the lens barrel. Although not shown in FIG. 2, as shown in FIG. 1, a reflecting mirror 26 that changes the optical path of the reflected light Lr reflected by the two-dimensional code Q or the like and incident on the reading port 11a is provided in the reading port 11a. Is provided.

Next, an outline of the configuration of the microcomputer system will be described. As shown in FIG. 2, the microcomputer system includes an amplifier circuit 31, an A / D conversion circuit 33, a memory 35, an address generation circuit 36, a synchronization signal generation circuit 38, a control circuit 40, an operation switch 42, an LED 43, a buzzer 44, and a liquid crystal. It comprises a display 46, a communication interface 48, and the like. As the name suggests, this microcomputer system is composed mainly of a control circuit 40 and a memory 35 that can function as a microcomputer (information processing apparatus). The image signal of the two-dimensional code Q imaged by the optical system described above. Etc. can be processed by hardware and software. The control circuit 40 also performs control related to the entire system of the information code reader 10. The liquid crystal display 46 constitutes a viewfinder that displays an image captured by the above-described light receiving sensor 23 of 640 × 480 pixels at 320 × 240 pixels.

The image signal output from the light receiving sensor 23 of the optical system is amplified by a predetermined cause by being input to the amplification circuit 31, and then converted from an analog signal to a digital signal when input to the A / D conversion circuit 33. . When the digitized image signal, that is, image data is input to the memory 35, it is stored in a predetermined input buffer. The synchronization signal generation circuit 38 is configured to generate a synchronization signal for the light receiving sensor 23 and the address generation circuit 36. The address generation circuit 36 is based on the synchronization signal supplied from the synchronization signal generation circuit 38. The storage address of the image data stored in the memory 35 can be generated.

The memory 35 is a semiconductor memory device, and corresponds to a reading object RAM (DRAM, SRAM, etc.) and a reading object ROM (EPROM, EEPROM, etc.), for example. The RAM of the memory 35 is configured to be able to secure a predetermined buffer area and a work area used by the control circuit 40 for each processing such as arithmetic operation and logical operation. The ROM stores in advance a predetermined program and a system program that can control each hardware such as the illumination light source 21, the light receiving sensor 23, the marker light source 25, and the like.

The control circuit 40 is a microcomputer capable of controlling the entire information code reader 10, and includes a CPU, a system bus, and an input / output interface. The control circuit 40 constitutes an information processing apparatus together with the memory 35 and has an information processing function. The control circuit 40 is configured to be connectable to various input / output devices (peripheral devices) via a built-in input / output interface. In the present embodiment, the power switch 41, the operation switch 42, the LED 43, A buzzer 44, a liquid crystal display 46, a communication interface 48, and the like are connected. Thereby, for example, monitoring and management of the power switch 41 and the operation switch 42, turning on / off the LED 43 functioning as an indicator, turning on / off the buzzer 44 capable of generating a beep sound and an alarm sound, and further reading the two-dimensional Screen control of the liquid crystal display 46 capable of displaying the evaluation result of the code Q, communication control of the communication interface 48 enabling serial communication with an external device, and the like are enabled. The operation switch 42 includes the trigger switch 14 that instructs the illumination light source 21 to irradiate the illumination light Lf.

The power supply system is configured by a power switch 41, a battery 49, and the like. By turning on / off the power switch 41 managed by the control circuit 40, the drive voltage supplied from the battery 49 to each device and each circuit described above is set. Continuity and interruption are controlled. The battery 49 is a secondary battery that can generate a predetermined DC voltage, and corresponds to, for example, a lithium ion battery.

Next, information code reading processing by the information code reading device 10 of the first embodiment will be described with reference to FIGS. 3 (A), 5, and 7.
FIG. 3A is a schematic diagram of resolution switching in the information code reading apparatus 10 of the first embodiment, and FIG. 5A is an explanatory diagram of a QR code imaged by switching the resolution.
The information code reader 10 according to the first embodiment is configured to be able to capture an image by switching between a low resolution (320 × 240) and a high resolution (640 × 480). The information code reader 10 first captures a QR code at a low resolution, determines whether the QR code can be decoded at the low resolution, and if it can be decoded, decodes the QR code from the captured low resolution image. To start. On the other hand, when it is determined that decoding is impossible at low resolution, the QR code is imaged at high resolution, and the QR code is decoded from the high resolution image. Here, when it is determined that decoding is impossible at a low resolution, an area E1 where the QR code Q exists is specified in the low resolution image as shown in the left diagram of FIG. When decoding from a high resolution image, the corresponding area E2 in the high resolution image is decoded as shown in the right diagram of FIG. 5A, thereby narrowing the decoding range and shortening the decoding time. ing.

FIG. 7 is a flowchart showing a QR code reading process by the information code reading device 10.
First, an image of QR code Q is acquired with a low resolution (320 × 240) (S12). As this low-resolution image, an image for the liquid crystal display 46 constituting the viewfinder can be used. Then, the rough position of the QR code (area E1 in the left diagram of FIG. 5A) and the module (cell) size are confirmed in the low-resolution image (S14). Here, a technique disclosed in Japanese Patent Laid-Open No. 2000-353210 is used for searching for a rough position of the QR code. On the other hand, the module size means the size of the module (cell) C constituting the QR code shown in FIG. 5B. Specifically, the information code reader 10 has the cell C (B). None (W) is identified as dark (cell present) or light (cell absent), and the size is confirmed by the number of pixels corresponding to the cell C at the low resolution (320 × 240). Next, it is determined whether the QR code is sufficient to be decoded in the image, that is, whether the QR code is properly captured by the operator and the QR code exists in the image (S16). Here, if the QR code is not properly captured (S16: No), the process is temporarily terminated.

When the QR code is sufficient to be decoded in the image (S16: Yes), is the module size confirmed in S14 described above, that is, whether the QR code can be decoded from the low resolution image? It is determined whether or not (S18). Here, it is determined whether the size of one module C shown in FIG. 5B is 4 pixels or more. Here, the size of the module C can be determined based on the presence of the module (dark B), the determination based on the absence of the module (bright W), or a combination of both.

When the module size is 4 pixels or more that can be decoded, that is, when the QR code can be decoded from the low resolution image (S18: Yes), the QR code is decoded from the low resolution image (S20). When the decoding is successful (S22: No), the decoding is terminated, the reading result is output (S34), and the process is terminated.

On the other hand, when the decoding at the low resolution fails (S22: Yes), as shown in the left diagram of FIG. 5C, the failed area ER is specified (S26). Then, an image is acquired with a high resolution (640 × 480) (S26), and the region ER that has failed to decode in the low resolution image is decoded (see the right figure in FIG. 5C), and the low resolution is finished. By complementing the decoding, the decoding is completed (S28). Then, the reading result is output (S34), and the process is terminated.

On the other hand, when it is determined that the QR code cannot be decoded from the low-resolution image of S18 described above (S18: No), the image is acquired at a high resolution (640 × 480) (S30), and the low-resolution image is converted at S32. Then, the area E2 that identifies the presence of the QR code is decoded (see the right figure in FIG. 5A). Then, the reading result is output (S34), and the process is terminated.

In the information code reading apparatus 10 of the first embodiment, the QR code position (area E1) is specified at a low resolution, and only the area E2 is decoded in the high resolution image, as shown on the left side of FIG. In addition, the position of the QR code is specified at a low resolution, and only the region E3 where the QR code exists (for example, 320 × 240 pixels, which is the same as the low resolution) is displayed at a high resolution as shown on the right side of FIG. It is also possible to capture an image (equivalent to 640 × 480).

In the information code reader 10 of the first embodiment, it is determined whether or not the information code can be read from the low-resolution image. When it is determined that the information code can be read, the information code is decoded from the low-resolution information code image. . Since decoding is performed with a low-resolution image, the information code can be read in a shorter time than when a high-resolution image is acquired and decoded. On the other hand, when it is determined that decoding from an image with a low resolution information code is impossible, decoding is performed from an image with a high resolution information code. For this reason, an information code can be read reliably. In particular, in order to determine whether or not decoding with a low-resolution image is possible in advance compared to decoding with a high-resolution image when decoding actually fails with a low-resolution image and decoding fails, The reading time of the information code can be shortened.

Further, the information code reading device 10 detects an area E1 where an information code exists from a low resolution image. Then, when decoding from the high-resolution information code image, the area E2 where the detected information code exists is decoded. For this reason, for example, it is impossible to decode a low-resolution information code from an image, and even when decoding from a high-resolution information code image, only the minimum area E2 where the information code exists is decoded. Therefore, decoding does not take time, and the information code can be read in a short time.

Further, in the information code reading device 10 of the first embodiment, whether or not the QR code can be read from the low resolution image is determined based on whether the module C constituting the QR code in the low resolution image has a preset pixel. Judgment is made based on whether the number is 4 or more. For this reason, it is possible to determine whether or not the QR code can be read without trying to decode a low-resolution image.

Furthermore, in the information code reader 10 of the first embodiment, when decoding fails with an image of a low resolution information code, the region ER where decoding has failed is specified. Then, the decoding from the high resolution image is performed in the failed area ER, and the decoding failure performed from the low resolution image is complemented. For this reason, even when decoding from an image with a low resolution information code fails and decoding from an image with a high resolution information code, the decoding that has already been completed with the low resolution image is used. Since only the minimum area that failed to be decoded is decoded, it takes no time for decoding, and the information code can be read in a short time.

In the first embodiment described above, the low-resolution image and the high-resolution image are acquired at different timings. However, it is also possible to acquire them simultaneously from the high-resolution image captured in advance. It is also possible to generate an image.

[Second Embodiment]
An information code reading apparatus 10 according to the second embodiment will be described with reference to FIGS. 3B and 6B.
The information code reader 10 of the second embodiment reads the information code at a high resolution when reading at a low resolution is not possible as in the first embodiment described above. However, in the second embodiment, when the information code is identified as a barcode or a QR code, when the barcode is identified as a barcode (one-dimensional code), an image of the barcode is acquired with high resolution only in the horizontal direction. Only when it is identified as a QR code (two-dimensional code), an image of the QR code is acquired with high resolution in the horizontal and vertical directions. In other words, for barcodes that do not require high resolution in the vertical direction (one-dimensional code), the barcode can be read in a short time by acquiring an image with high resolution only in the horizontal direction. Yes.

A barcode and QR code reading process by the information code reader 10 of the second embodiment will be described with reference to a flowchart shown in FIG.
The processes from S12 to S28 are the same as those in the first embodiment described above with reference to FIG. Here, when it is determined whether the size of the module in S18 can be decoded, that is, whether the information code can be decoded from the low-resolution image, it is determined that the information cannot be decoded at the low resolution (S18: No). ) Based on the information code shape (square or rectangular), it is determined whether it is a bar code or a QR code (S29). When it is determined that the barcode is used (S29: Yes), as shown in FIG. 6B, an image is captured at a high resolution (640 × 240) in which the resolution is increased only in the horizontal direction (S31). ). Here, it is assumed that the operator is imaging the barcode in such a manner that the horizontal direction of the barcode and the horizontal direction of the information code reading device 10 substantially coincide. However, if it is determined that the barcode direction is the vertical direction in an image with a low resolution, an image with a high resolution in the vertical direction may be captured.

On the other hand, when it is determined that the code is a QR code (S29: No), as shown in FIG. 6C, an image is captured at a high resolution (640 × 480) in which the resolution in the horizontal and vertical directions is increased ( S30). Since the subsequent processing is the same as that of the first embodiment, description thereof is omitted.

[ Reference example ]
An information code reader 10 according to a reference example will be described with reference to FIG.
The information code reader 10 according to the first and second embodiments can capture images at two resolutions, low resolution and high resolution. On the other hand, as shown in FIG. 4, in the embodiment of the reference example , low resolution (320 × 240), medium resolution (640 × 480), high resolution (1280 × 960), and high high resolution (2560 × 19200). 4 resolutions can be switched, the resolution required for reading is determined based on the low resolution (320 × 240) image, and the information code is captured with the minimum necessary resolution. Read.

The QR code reading process by the information code reading device 10 of this reference example will be described with reference to the flowchart shown in FIG.
First, an image of QR code Q is acquired with a low resolution (320 × 240) (S52). Then, whether or not the size of the module C can be decoded, that is, whether or not the QR code can be decoded from the low-resolution image, is determined based on whether the size of the module C (see FIG. 5B) is 4 pixels or more. (S54). When the size of the module C is 4 pixels or more that can be decoded, that is, when the QR code can be decoded from the low resolution image (S54: Yes), the QR from the low resolution (320 × 240) image is displayed. The code is decoded (S66).

On the other hand, when the size of the module C is less than 4 pixels, that is, when the QR code cannot be decoded from the low resolution (320 × 240) image (S54: No), the size of the module C is less than 4 pixels and 3 pixels. That is, it is determined whether decoding is possible with 3 pixels and medium resolution (640 × 480) (S56). Here, when the QR code can be decoded from the medium resolution image (S56: Yes), the medium resolution (640 × 480) image is acquired (S60), and the QR code is decoded from the acquired medium resolution image. Perform (S66).

On the other hand, when the size of the module C is less than 3 pixels, that is, when the QR code cannot be decoded from the medium resolution (640 × 480) image (S56: No), the size of the module C is less than 3 pixels and 2 pixels. That is, it is determined whether or not decoding is possible with two pixels and high resolution (1280 × 960) (S58). Here, when the QR code can be decoded from the high-resolution image (S58: Yes), the high-resolution (1280 × 960) image is acquired (S62), and the QR code is decoded from the acquired high-resolution image. Perform (S66).

On the other hand, when the size of the module C is less than two pixels, that is, when decoding cannot be performed even with a high resolution (1280 × 960) image (S58: No), a high high resolution (2560 × 1920) image is acquired ( In S64, the QR code is decoded from the acquired high-resolution image (S66).

In the information code reader 10 of the reference example , since the resolution required for reading is determined based on the low-resolution image, the information code can be reliably read, and the information code is read with the minimum necessary resolution. It is possible to shorten the reading time of the information code. In the reference example , four levels of resolution are prepared. However, any number of levels can be applied as long as the number is three or more.

It is sectional drawing of the information code reader which concerns on 1st Embodiment of this invention. It is a block diagram which shows the structure outline | summary of the circuit part of the information code reader which concerns on 1st Embodiment of this invention. FIG. 3A is a schematic diagram of resolution switching in the information code reader of the first embodiment, and FIG. 3B is a schematic diagram of resolution switching in the information code reader of the second embodiment. It is a schematic diagram of the resolution switching in the information code reader of a reference example . FIGS. 5A and 5C are explanatory diagrams of QR codes captured by switching the resolution with the information code reader according to the first embodiment, and FIG. 5B is a module (FIG. 5B) that configures the QR codes. It is explanatory drawing of a cell. FIG. 6A is an explanatory diagram of a QR code imaged by switching the resolution with an information code reader according to another example of the first embodiment, and FIG. 6B is an information code reader of the second embodiment. FIG. 6C is an explanatory diagram of a QR code imaged with the resolution switched by the information code reader according to the second embodiment. It is a flowchart which shows the reading process of QR code by the information code reading apparatus which concerns on 1st Embodiment. It is a flowchart which shows the reading process of the barcode and QR code by the information code reader which concerns on 2nd Embodiment. It is a flowchart which shows the reading process of QR Code by the information code reader which concerns on a reference example .

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Information code reader 20 Circuit part 23 Light reception sensor 35 Memory 40 Control circuit

Claims (5)

An information code reading device for reading an information code comprising:
Low resolution image acquisition means for acquiring an image of an information code at a low resolution in a substantially same imaging region, and high resolution image acquisition means for acquiring an image of the information code at a higher resolution than the low resolution image acquisition means When;
Determining means for determining whether or not an information code can be read from the low resolution image;
Decoding means for decoding from the low resolution information code image when it is determined to be readable by the determination means, and decoding from the high resolution information code image when it is determined impossible; equipped with a,
The decoding means includes
When decoding is performed from the image of the information code of the low resolution and decoding fails, an area where decoding has failed is identified,
The decoding which has already been completed with the low resolution image is used, the decoding failure area is decoded from the high resolution image, and the decoding failure made from the low resolution image is complemented. Information code reader. A presence region detecting means for detecting a region where an information code is present from the low resolution image;
2. The decoding unit according to claim 1, wherein when the decoding unit performs decoding from an image of the high-resolution information code, the decoding unit decodes a region where the information code detected by the presence region detection unit exists. Information code reader. The determination means determines that the information code can be read when at least one of the minimum units of light and dark that constitute the information code in the low resolution image is equal to or more than a preset number of pixels. The information code reading device according to claim 1 or 2. When it is judged unreadable by the determining means, the high at resolution image acquisition means higher resolution any one of claims 1 to 3, characterized in that to obtain the image of the information code Information code reader. An information code identifying means for identifying whether the information code is a one-dimensional code or a two-dimensional code;
When identified as a one-dimensional code, the high-resolution image acquisition means acquires an image of the one-dimensional code at a high resolution only in the horizontal direction,
5. The information code reading apparatus according to claim 4 , wherein when the image is identified as a two-dimensional code, the high-resolution image acquisition means acquires the image of the two-dimensional code at a high resolution in the horizontal and vertical directions.

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