JP4058478B2 - Optical information reading method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a reading method for optically reading a plurality of information codes expressed for each partial data in a state where predetermined data is divided into partial data, and an optical information reading device using the method. .
[0002]
[Prior art]
Conventionally, optical information readers are widely used in POS systems, OA systems, FA systems, etc., for example, for optically reading information codes such as barcodes and two-dimensional codes printed and displayed on paper. Generally used as a device. In order to print and display such an information code on, for example, paper, it is necessary to secure a predetermined display space, and the indispensable display space is defined according to the information amount of the information code.
[0003]
Generally, the display space increases as the information amount of predetermined data expressed by an information code increases. Therefore, in recent years, in preparation for the case where such a display space is limited, predetermined data is divided into partial data, each partial data is represented by a partial information code, and the predetermined data is expressed by a plurality of partial information codes. In recent years, expression has been carried out. Note that Patent Document 1 discloses an example of an optical information reading apparatus that can prevent information on another reading target adjacent to a desired reading target from being erroneously read.
[0004]
[Patent Document 1]
JP 2001-147987 A
[0005]
[Problems to be solved by the invention]
There is provided a reading device for reading a plurality of partial information codes by placing each partial information code in a reading visual field region of the optical information reading device one by one. Reading each time is not preferable because reading and decoding time becomes longer.
[0006]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an optical information reading apparatus and a reading method thereof that can shorten the reading time for reading a plurality of partial information codes. .
[0007]
[Means for Solving the Problems]
  Claim1According to the described invention, in the case of reading a plurality of partial information codes in order to capture image data including partial information codes in the reading visual field region and collectively decode the partial information codes included in the captured image data Even so, the reading time can be shortened.
[0008]
  Moreover,When the partial information code is composed of an information pattern and a specific pattern, the specific pattern and its number are detected from the captured image data, and are included in the image data based on the number of detected specific patterns. The number of partial information codes is determined, and all partial information codes included in the reading visual field area are optically read in order to decode the partial information codes corresponding to the number determined based on the specific pattern of the partial information code. Can do.
[0009]
  According to the second aspect of the present invention, when the partial information code to be decoded corresponding to the order information of the partial information code and the information to be read is successfully decoded, other partial information is preset. When the partial information code set as the decryption target is decrypted to finish the decryption of the code, it is not necessary to decrypt all the partial information codes included in the captured image data, and the partial information code to be decrypted Can be read quickly.
  According to the invention described in claim 3, in the invention described in claim 1 or 2, when the partial information code is composed of an information pattern and a plurality of specific patterns, a plurality of images are taken from the captured image data. Extract a specific pattern, calculate parameters such as the distance between the extracted specific patterns, and perform a calculation process based on a predetermined evaluation formula for the calculated parameter to satisfy a predetermined evaluation standard In order to interpret a plurality of specific patterns extracted when it is determined that the predetermined evaluation standard is satisfied as a position reference of the partial information code, a plurality of specific patterns are included in each partial information code. Even if the reading visual field region includes a plurality of partial information codes, if a predetermined evaluation criterion is appropriately set, a plurality of specific patterns are included. Compare the over emissions extracted at random to decrypt the particular pattern as the position reference can be a successful quick decryption processing.
[0010]
According to the invention described in claim 4, in the invention described in any one of claims 1 to 3, the partial information code includes an information pattern and a specific pattern serving as a position reference for specifying the position of the information pattern. If it is, a plurality of specific patterns are detected from the captured image data, and the entire outline of the partial information code included in the image data captured based on the detected plurality of specific patterns Is detected, and the boundary between the partial information codes is detected based on the entire external shape of the detected partial information code and a plurality of specific patterns, so that it is quickly detected when the boundary of each partial information code is detected. can do.
[0011]
By the way, when partial information codes are decoded at once as described above, it is often the case that a plurality of partial information codes are taken in image data in substantially the entire reading visual field region. Therefore, for example, when image data is taken in, if there is a brightness spot in the reading visual field area due to optical characteristics on the reading device side (for example, when the end portion is darker than the center portion), all at once. Even if it is decrypted, all partial information codes are determined as decryption failures. If batch decoding fails, image data is taken in again and batch decoding is performed, but time is wasted.
[0012]
Therefore, according to the invention described in claim 5, in the invention described in any one of claims 1 to 4, the partial information code includes an information pattern and a specific pattern serving as a position reference for specifying the position of the information pattern. In addition, when the information indicated by those information patterns includes division number information and rank information of partial information codes, after any partial information code of a plurality is decoded, The position of the decoded partial information code, the information pattern division number information and the order information are stored in association with each other, and the decoding fails until all of the partial information codes included in the captured image data are successfully decoded. In such a case, the image data is taken in again, and the position of the stored partial information code is determined before re-decoding a plurality of partial information codes included in the retaken image data. , In order to read the division number information and the order information of the information pattern and to decode the partial information code other than the position of the decoded partial information code preferentially again. There is no need for decryption, and the decryption process can be performed quickly.
[0013]
In the invention according to any one of claims 2 to 5, as in the invention according to claim 6, the specific pattern comprises a geometric pattern or a light / dark pattern located at a predetermined location of the partial information code. If it is, it can be suitable as a position reference for locating the partial information code. It should be noted that the geometric pattern includes a pattern composed of a square, a triangle, a rhombus, a polygon, a circle, an L shape, a U shape, and a combination of the patterns.
[0014]
According to the invention described in claim 7, in the invention described in any one of claims 1 to 6, the partial information code includes an information pattern and a specific pattern serving as a position reference for specifying the position. In this case, two specific patterns are sequentially detected from the captured image data, and the partial information code not detected based on the measured distance interval or the position of the specific pattern of the partial information code is estimated. In particular, when three or more partial information codes are included in the captured image data, a partial information code or a specific pattern of the partial information code can be searched at the estimated existence estimated position, and a partial Information codes can be searched.
[0016]
  Claim8According to the described invention, claims 1 to7If a plurality of partial information codes cannot be decoded by the optical information reading method described in any of the above, information such as the order information of the decoded partial information codes and information on the object to be read is output, so that the information can be decoded. The information indicated by the partial information code can be output. Moreover, since it is notified that there is a partial information code that has not been decoded, it is possible to notify the operator that the partial information code has not been decoded.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
Hereinafter, a first embodiment in which the present invention is applied to a two-dimensional code reader will be described with reference to FIGS.
FIG. 2 schematically shows an electrical configuration of the two-dimensional code reader.
A two-dimensional code reading device (hereinafter referred to as a reading device main body) 1 as an optical information reading device has a two-dimensional information code B such as a QR code configured by arranging cells of a light and dark pattern in a two-dimensional matrix. It is for optical reading. In this embodiment, an embodiment for reading a QR code will be described.
[0018]
The reading device body 1 includes a power supply circuit 2, a control circuit 3, a memory 4 as a storage unit, an operation unit 5, an illumination drive circuit 6, an irradiation unit 7, an imaging unit 8, a sensor drive circuit 9, an optical sensor 10, and a waveform. A shaping unit 11, an external interface unit 12, and a display unit 13 as notification means are provided. The control circuit 3 functions as the decoding means and the taking-in means of the present invention. The power supply circuit 2 is configured by, for example, an AC / DC converter, and converts AC power supplied from the outside into DC and supplies DC power to all the components of the reader main body 1.
[0019]
The control circuit 3 is constituted by, for example, a microcomputer, and electrically controls the reading apparatus main body 1 based on a control program. The operation unit 5 is provided with various operation setting keys such as a trigger key and a numeric key. For example, when the trigger key is operated by an operator or the like, an operation signal is given to the control circuit 3, and the control of the control circuit 3 is performed. The reading apparatus main body 1 operates based on the above. The illumination drive circuit 6 gives a drive signal to the irradiation unit 7 based on the control of the control circuit 3. The irradiation unit 7 is configured by, for example, an LED or the like, and irradiates the reading object A with light when a driving signal is given from the illumination driving circuit 6.
[0020]
The image forming means 8 is constituted by, for example, a lens, forms an image of the light irradiated and reflected from the irradiation unit 7 onto the reading object A, and guides the reflected light to the optical sensor 10. The optical sensor 10 is also referred to as an area sensor, for example. Light receiving elements such as CCDs are arranged on a two-dimensional plane, and photoelectrically convert reflected light reflected on the reading object A. The exposure time for exposure by the optical sensor 10 is configured to be set by the control circuit 3.
[0021]
The sensor driving circuit 9 is configured to give a clock for outputting a pixel signal from the light receiving element of the optical sensor 10 to the optical sensor 10, and the control circuit 3 passes the optical sensor through the sensor driving circuit 9. When driving 10 is controlled, the optical sensor 10 provides the waveform shaping unit 11 with a photoelectrically converted signal.
[0022]
The waveform shaping unit 11 amplifies the signal photoelectrically converted by the optical sensor 10 and gives a signal of a luminance level to the control circuit 3. The amplification factor of the waveform shaping unit 11 is configured to be set by the control circuit 3. The external interface unit 12 inputs and outputs data between the control circuit 3 and an external device (not shown).
[0023]
<About partial information code>
Here, the partial information code that is read by the reading device main body 1 will be described. FIG. 3 shows an example of the two-dimensional information code. The two-dimensional information code BB includes an information pattern B1 and a positioning pattern (specific pattern) B2 serving as a position reference. Generally, the display space D increases as the information amount of all data that needs to be expressed by the two-dimensional information code B increases. For example, in the case of the QR code, small black and white (bright and dark) square cells are arranged in the vertical and horizontal directions and are formed in a certain predetermined square, so that the display space D has a rectangular shape and should be expressed by the QR code. When the amount of information of all data is large, there is a case where one QR code including all data information is formed and cannot be displayed even if it is displayed in the display space D (see FIG. 3A). Therefore, all data is divided into partial data, and each partial data is expressed by a partial information code B and displayed in the display space D (see FIG. 3B). Such a partial information code is also called a concatenated code.
[0024]
In the case of a QR code as shown in FIGS. 3A and 3B, the positioning pattern (specific pattern) B2 is combined with an outer frame (dark spot), a middle frame (bright spot), and an inner frame (dark spot). The ratio of the light-dark pattern is defined as 1 (dark spot): 1 (light spot): 3 (dark spot): 1 (light spot): 1 (dark spot), and the partial information code Used as a position reference for locating B (see FIG. 3).
[0025]
In the case of the partial information code B based on the QR code, the data of the information pattern B1 portion included in each partial information code B includes a connection mode identifier, code number information, division number information, a parity part, and a data part.
[0026]
Among these, the connection mode identifier is a partial information code (that is, a partial information code) expressed for each partial data in a state where predetermined data is divided, or one independent information code. The identification part (flag) for discriminating whether it is is shown. The code number information indicates number information that functions as order information of the partial information code, and indicates an identification unit for determining which number of partial information code the partial information code is. The division number information indicates an identification unit for determining how many pieces of the information pattern are divided. Furthermore, the parity part is an identification part provided so that the same code is allotted to each of the series of partial information codes and is not mistakenly distinguished from other information codes. The data portion includes an original data value and an error correction code for error correction.
[0027]
The operation of the above configuration will be described with reference to FIG.
When the trigger switch of the operation unit 5 is operated by the operator in a state where a plurality of partial information codes are included in the reading visual field area A (see FIG. 2) of the reading apparatus body 1, the control circuit 3 is given a reading instruction signal, and the reading apparatus main body 1 starts a batch decoding process of a plurality of partial information codes as shown in FIG. At this time, the control circuit 3 sets exposure conditions in S1 (S1). This exposure condition indicates the exposure time of the optical sensor 10 and the amplification factor of the amplification circuit in the waveform shaping unit 11, and is set based on the control of the control circuit 3.
[0028]
The control circuit 3 captures image data in the reading visual field area A of the optical sensor 10 (S2). As described above, when the control circuit 3 takes in the image data for one image area from the waveform shaping unit 11, the brightness level is detected for each pixel, and the brightness level equal to or higher than a predetermined first threshold value is set. A point (white), a luminance level equal to or lower than a predetermined second threshold value is converted into binarized data so as to correspond to a dark point (black) (converted to a digital value representing a light point or a dark point), Image data is taken in by storing binary data of image data in the memory 4 for each pixel. Then, the control circuit 3 cuts out the partial information code from the image data stored in the memory 4.
[0029]
<About partial information code extraction processing>
This information code cutting process indicates a process of cutting out a partial information code by separating an information code included in the image data of the reading visual field area A from a background image. In the information code cutout process of the present embodiment, the control circuit 3 also performs a process of dividing a plurality of partial information codes included in the captured image data into individual partial information codes. The processing contents will be described below with reference to FIG.
In FIG. 4, the control circuit 3 searches and detects the positioning pattern B2 from the captured image data (T1). At this time, the control circuit 3 counts and detects the number of positioning patterns B2 included in the captured image data (T2). The control circuit 3 determines the number of partial information codes B included in the image data based on the number including the positioning pattern B2. Specifically, in the case of the QR code shown in FIG. 3, since the positioning pattern B2 is located at three positions, the upper left part, the upper right part, and the lower left part of the entire partial information code B, the positioning pattern B2 is included in the image data. In the case where the number of exists is 9, it can be determined that 9/3 = 3.
[0030]
The control circuit 3 detects the entire outer shape of the positioning pattern B2 from the image data stored in the memory 4, and also detects the boundary between the partial information codes B based on the plurality of positioning patterns B2. Specifically, the control circuit 3 calculates a boundary between each partial information code B by proportional calculation, and cuts out each partial information code B2 at this boundary (T4 to T6). A detailed example of this is shown in FIG. In FIG. 5A, the control circuit 3 detects the corner of the positioning pattern B2. The control circuit 3 detects corners on one side and the other side where the positioning patterns B2 are arranged in a straight line (refer to the C1 to C2 and C3 to C4 portions in FIG. 5A). Further, the control circuit 3 detects the position of the corner of another positioning pattern B2 (including, for example, the portion C5 in FIG. 5A and other corners).
[0031]
Then, the control circuit 3 calculates the distance between the corners. For example, the distances between C1 and C5, between C5 and C2, and between C3 and C4 are calculated. Thereafter, by searching for a distance between corners that is substantially the same distance as the distance between corners C3 and C4 on one side, corners C1 and C5 are estimated as corresponding corners on the other side as corners corresponding to corners C3 and C4. To do.
[0032]
The control circuit 3 detects the outer shape of the partial information code B using the proportional relationship between the corresponding corners. That is, using the fact that (distance between C1 and C5) :( distance between C5 and C2) = (distance between C3 and C4) :( distance between C4 and C6), the position of corner C6 is calculated by proportional calculation. Thus, the entire outer shape of the plurality of partial information codes B is detected.
[0033]
As described above, since the position of the positioning pattern B2 in the QR code is determined in advance as described above, the corner where the positioning pattern B2 exists is detected by a corner where the positioning pattern B2 does not exist (for example, Compared with the detection of the corner C6 at the lower right of the outer shape of the partial information code B), it can be detected without taking time. Therefore, the entire outer shape of the plurality of partial information codes B can be quickly detected by using proportional calculation as described above.
[0034]
Hereinafter, a method for cutting out each partial information code B will be described with reference to FIG. After detecting the entire outer shape of the partial information code B, the control circuit 3 detects the boundaries of the individual partial information codes B. Specifically, the control circuit 3 detects the corners C7 and C8 of the positioning pattern B2 on the upper side (other side) of the positioning pattern B2, and detects the corners C9 and C10 where the positioning pattern B2 of the partial information code B does not exist. The position is calculated by proportional calculation in the same manner as described above. Thereby, the boundary between the partial information codes B and B can be calculated and detected by proportional calculation, and when the boundary of each partial information code B is detected and cut out, it can be performed quickly. When the control circuit 3 detects the entire outer shape of the partial information code B and the boundaries between the individual partial information codes B and B, the control circuit 3 ends the extraction process of the partial information code B.
[0035]
Returning to FIG. 1, when the cutting process of the partial information code B is completed, the control circuit 3 decodes one of the partial information codes B using the positioning pattern B2 detected correspondingly as a position reference (S4). Since this decoding process is the same as the conventional decoding (decoding) process of the information code, its description is omitted. Here, when the decoding process of the partial information code B fails (S5: NO), the control circuit 3 repeats the process from the exposure condition setting process of S2 again, but if the decoding is successful (S5: YES), it is decoded. It is determined whether or not the information code is the partial information code B.
[0036]
Specifically, the control circuit 3 determines whether or not it is the partial information code B by determining the connection mode identifier in the information pattern B1 of the decoded partial information code B. At this time, the control circuit 3 ends if it is a single information code, but if it is determined that it is the partial information code B, the processing from S7 is performed.
[0037]
In S7, the control circuit 3 stores the decoded position of the partial information code B in the built-in memory. For example, in FIG. 5, when the control circuit 3 decodes the partial information code B located at one end (for example, the left end) in the reading visual field area A, the corners C1, C3, C8 of the calculated partial information code B are obtained. , C10 is stored. Further, the control circuit 3 stores the division number information and the code number information in the memory (S8), and stores the decoded data (S9).
[0038]
Then, the control circuit 3 decodes the next partial information code B (S10). At this time, the control circuit 3 decodes, for example, the partial information code B included in the central portion of the image data in the reading visual field area A. When the next partial information code B is successfully decoded, the control circuit 3 determines whether or not all the code number information is prepared, and if not, repeats the process from S7. In S11, if the decoding is not successful, the control circuit 3 sets the exposure condition again (S13), fetches the image data (S14), and determines whether or not the difference between the brightness levels of the bright and dark spots is greater than or equal to a predetermined level. (S15).
[0039]
The processing of S15 will be described in detail. When the image data for one image area is given from the waveform shaping unit 11, the control circuit 3 has a luminance level assumed to be a bright point in the entire image data. The minimum value is compared with the maximum value of the luminance level assumed to be a dark spot, and it is determined whether or not the difference is greater than or equal to a predetermined level. This is performed in order to determine whether or not the exposure conditions are properly set and whether or not the partial information code B is included in the image data. That is, if the difference is not greater than or equal to the predetermined level, the control circuit 3 determines that the exposure condition is not set appropriately or the partial information code B is not included in the image data, and returns to S13 to perform the process again. . Conversely, if the difference is greater than or equal to the predetermined level, the control circuit 3 determines that the partial information code B is included in the image data, and proceeds to S16. Then, the control circuit 3 performs a cutting process of the partial information code B other than the stored position (S16).
[0040]
Specifically, the control circuit 3 reads the division number information and the code number information of the decoded partial information code B, and cuts out the partial information code B other than the position of the decoded partial information code B. For example, when the control circuit 3 cuts out the partial information code B at the center, in FIG. 5B, from the positions of the corners C1, C3, C2, C6 and the position of the corner C7 of the plurality of partial information codes. The position of the corner C9 is calculated, and only the partial information code B at the center is cut out. That is, the cutting process is performed without calculating the positions of the corners C8 and C10. Thereby, the cutting-out process of the partial information code B can be performed quickly.
[0041]
Then, the control circuit 3 preferentially decodes the partial information code B at the center in the reading visual field area A (S17). At this time, without decoding the partial information code B located at the one end, the central partial information code B is preferentially decoded, so that the partial information code B once successfully decoded is not decoded again, The decoding process can be performed quickly.
[0042]
If the control circuit 3 succeeds in decoding, the process proceeds to S12. If the decoding is not successful, the process returns to S13 and repeats the process. These S7 to S18 are repeated until all the code number information is obtained (S12: YES). That is, as shown in FIG. 5, when a plurality of partial information codes B are included in the image data taken in the control circuit 3 of the reading device body 1, the control circuit 3 has one end portion, a central portion, If the three partial information codes B located at the other end are successfully decoded, the code number information is obtained.
[0043]
Then, the control circuit 3 combines the data of the partial information codes B (S19) and ends. In this manner, the control circuit 3 can take in the image data including the plurality of partial information codes B and collectively decode the plurality of partial information codes. The control circuit 3 desirably decodes a plurality of partial information codes B included in the reading visual field area A at a time.
[0044]
According to the present embodiment, image data including a plurality of partial information codes B is taken in, and a plurality of partial information codes included in the captured image data are collectively decoded. It can be shortened.
[0045]
The control circuit 3 takes in image data including a plurality of partial information codes B, decodes one partial information code B, and if the next partial information code is not successfully decoded, the position of the decoded partial information code Since the partial information code cutting process and decoding process other than the above are performed, the reading time can be shortened.
[0046]
(Second Embodiment)
FIG. 6 and FIG. 7 are for explaining the second embodiment of the present invention. The difference from the first embodiment resides in the partial information code cutting processing operation. The same parts as those in the first embodiment are denoted by the same reference numerals and the description thereof is omitted.
In FIG. 6 schematically showing the cutting process of the partial information code B, the control circuit 3 detects the positioning pattern B2 from the captured image data (U1) as in the first embodiment, The number of positioning patterns B2 is detected (U2). The control circuit 3 determines the number of partial information codes B (U3). At this time, the control circuit 3 appropriately extracts the three positioning patterns B2 included in the partial information code B (U4). The positioning pattern B2 is appropriately extracted from the detected positioning pattern B2. Thereafter, the control circuit 3 calculates the distance and angle (corresponding to the parameters) between the positioning patterns B2 (U5), and sequentially stores the evaluation values in the memory in correspondence with the positions of the positioning patterns B2 (U6). This evaluation value f is expressed as in equation (1).
[0047]
f = α · abs (θ−90 °) + β · abs (x / y−1) (1)
This expression (1) corresponds to a predetermined evaluation calculation expression of the present invention. Here, abs represents an absolute value function, α and β are positive coefficients, θ is an angle formed between the centers of the three extracted positioning patterns B2, and x and y are distances between the positioning patterns B2. Represents.
[0048]
The evaluation value f is such that a smaller value is obtained as the angle θ approaches 90 °, and a smaller value is obtained as the distance x approaches the distance y, with 0 being the best value. At this time, the control circuit 3 determines whether or not the evaluation standard is satisfied by determining whether or not the evaluation value f is equal to or less than a threshold value (within an allowable error range) (U7). When the evaluation value f is equal to or less than the threshold value, the control circuit 3 performs the cutting process at this boundary (U8).
[0049]
This process will be specifically described below. For example, referring to FIG. 7, when three positioning patterns B2 of XYD are extracted from the positioning patterns B2, the distance c between XY and the distance b between X-D are the same even if the vertex is X. Therefore, the evaluation value f is relatively large. Therefore, the cutting process and the decoding process are not performed with the three positioning patterns B2 of XYD.
[0050]
When the three positioning patterns B2 of XYZ are extracted from the positioning pattern B2, when the vertex is X, the distance c between XY and the distance a between X and Z are substantially the same, and θ = ∠ Since YXZ = approximately 90 °, the evaluation value f is approximately 0. In addition, when the vertex is set to Y or Z, a large evaluation value f is obtained. That is, if three positioning patterns B2 of XYZ are extracted and the value of the evaluation value f satisfies the evaluation criteria, the XYZ positioning pattern B2 is cut out in a two-dimensional plane range positioned at the outer frame end.
[0051]
In this case, in the case of the QR code, when the three positioning patterns B2 are extracted, the two-dimensional plane range where the three positioning patterns B2 are positioned at the outer frame end is determined. The cut-out process is performed in the plane range within the outer frame end. Therefore, the control circuit 3 extracts the Y and Z positioning patterns B2 having X as the apex, and performs the cutting process.
[0052]
In particular, in the case of cutting out a QR code, it has been confirmed that if the extracted position specifying pattern B2 is randomly extracted and the QR code is cut out and decoded, the processing requires a lot of time. Thus, after it is determined that the predetermined evaluation standard is satisfied, the extraction processing time and the decoding time can be shortened by performing the extraction processing based on the extracted three positioning patterns B2.
[0053]
When the cut-out process is performed in U8, the control circuit 3 determines whether or not all the partial information codes B2 have been cut out (U9). If the cut-out process for all the partial information codes B2 has not been completed, the control circuit 3 again returns to U4. Repeat the process.
[0054]
On the other hand, when it is determined in U7 that the evaluation value f exceeds the threshold value, the control circuit 3 determines whether there is another combination for extracting the positioning pattern B2 (U10). That is, the control circuit 3 appropriately extracts three positioning patterns B2 in U4, but determines whether there are other combinations of the positioning patterns B2. If it is determined that there is another combination (U10: YES), the control circuit 3 returns to U4 again and repeats the process.
[0055]
On the other hand, if the control circuit 3 determines in U10 that there is no other combination of the positioning pattern B2, the minimum value (that is, the best) is obtained from the evaluation values f stored in the memory in U6. The selected three positioning patterns B2 are selected (U11), and a cutting process is performed at the boundary of the selected positioning patterns B2. When the control circuit 3 cuts out all the partial information codes B2 in U9, the partial information code B cut-out process is terminated. When the cut-out process is completed, the control circuit 3 interprets the three positioning patterns B2 extracted and cut out in this way as the position reference of the partial information code B. The other parts are substantially the same as those of the above-described embodiment, and the description thereof is omitted.
[0056]
According to the present embodiment, three positioning patterns B2 are extracted from the captured image data, and parameters of distance and angle between the extracted three positioning patterns B2 are calculated. Since the extracted three positioning patterns B2 are regarded as the position reference of the partial information code B on the condition that the evaluation value f of the expression (1) is equal to or less than the threshold value based on the angle and the angle, the decoding is performed. Processing can be done quickly.
[0057]
(Third embodiment)
FIG. 8 and FIG. 9 are for explaining the third embodiment of the present invention, and the difference from the first embodiment is in the batch decoding process. Only the parts different from the first embodiment will be described below.
The data code (corresponding to the partial information code B) is also called a DataMatrix code. As shown in FIG. 9, an example of the pattern is an information pattern B1 made up of cells called timing cells, An L-shaped positioning pattern (specific pattern) B2 is provided. The reader main body 1 can decode the data code using the positioning pattern B2 as a position reference by detecting the L-shaped positioning pattern B2.
[0058]
This operation will be described below with reference to FIG. The control circuit 3 sets exposure conditions (V1). Then, the control circuit 3 takes in the image data including the plurality of partial information codes B in the reading visual field area A (V2), and searches for the dark spot from the image data, thereby the L of the partial information code B from one end (left end) side. After detecting the letter-shaped positioning pattern B2, the partial information code B is decoded by cutting it out, detecting the next central L-shaped positioning pattern B2, and then cutting out the detected partial information code B. Then, processing is performed until the decoding is completed (V3 to V8).
[0059]
When the detection of the two L-shaped positioning patterns B2 is sequentially performed in this way, the control circuit 3 measures the distance L between the dark spots of the end B2a constituting the L-shaped positioning pattern B2 (V9). ), A distance L measured in the extending direction from the end B2a of the partial information code B detected at the left end (previous) to the end B2a of the partial information code B detected at the center (next) The existence position of the L-shaped partial information code B is estimated in the vicinity of the position separated by only (V10). At this time, the control circuit 3 sets a search area E where the positioning pattern B2 exists.
[0060]
This search area E indicates the existence estimation range of the L-shaped positioning pattern B2 located at the right end that is not detected (see FIG. 9). The control circuit 3 searches and detects the dark spot of the positioning pattern B2 and the L-shaped positioning pattern B2 in the search area E (V11).
[0061]
Thereafter, the control circuit 3 cuts out and decodes the partial information code B from which the positioning pattern B2 has been detected (V12). The control circuit 3 determines whether or not the code number information obtained when decoding the information pattern B1 is complete (V13). If not, the control circuit 3 returns to V10 and further performs a process of estimating the presence position. The control circuit 3 combines the data when the code number information is complete (V14), outputs the data, and ends.
[0062]
In this case, when searching for the partial information code B at the right end, the control circuit 3 searches only for the search area E where the existence position of the positioning pattern B2 is estimated. Therefore, as shown in FIG. Even if the dirty portion F is included in the image data between the position of the partial information code B at the center and the position of the partial information code B at the right end when The partial information code B at the right end can be detected without detecting the dirty portion F as a dark spot. Thereby, the partial information code B can be searched and detected quickly.
[0063]
(Fourth embodiment)
FIGS. 10 to 14 are for explaining a fourth embodiment of the present invention, and show an embodiment in which a partial information code is read and decoded on an inspection line of a factory or the like. In FIG. 10 showing a schematic configuration of this inspection line, the reader main bodies 1... 1 are installed on both sides of the inspection line Z for each of the four steps (1) to (4). A computer 14 that performs overall control of these devices is connected to each of these reading device bodies 1...
[0064]
A label X on which four partial information codes B... B are printed is affixed to the inspection object Y flowing on the inspection line Z. FIG. 11 schematically shows the contents of the label X. The data value of the information pattern B1 of the four partial information codes B ... B printed on the label X includes the product number information of the inspection object Y, the lot number information of the inspection object Y, and the manufacture of the inspection object Y, respectively. Reading object information such as date information and manufacturing place information of the inspection object Y is included and expressed.
[0065]
At this time, while moving the inspection object Y on the inspection line Z, it is possible to set a work line process for decoding the partial information code B... B printed on the label X for each process (1) to (4). (See FIGS. 12 and 14). That is, the memory 4 of each reading device body 1 stores each reading object information (part number information, lot number information, manufacturing date information, manufacturing location information) to be decoded in each step (1) to (4). When each control circuit 3 collectively decodes the partial information code B included in the reading visual field area A, the partial information code B to be decoded set for each reading apparatus body 1 based on this information. Decipher. The details of the batch decoding are the same as those in the above-described embodiment, and thus description thereof is omitted.
[0066]
Therefore, in the process (1), the partial information code B indicating the product number information is decoded, in the process (2), the partial information code B indicating the lot number information is decoded, and in the process (3), the partial information indicating the manufacturing date information. The code B is decoded, and in the step (4), the partial information code B indicating the manufacturing location information is decoded. Therefore, only the necessary partial data is generated as the partial information code B in each step (1) to (4), printed on the label X having a predetermined display space, and affixed to the inspection object Y. The control circuit 3 of the reading device main body 1 1 to 4 can reliably decode the necessary partial information code B.
[0067]
Further, as shown in the flowchart of a part of the flow of the control operation in FIG. 13, when decoding the partial information code B corresponding to the code number information and the reading object information set in the reading device body 1, When it is determined that the partial information code B has been successfully decoded, the partial information code B may be immediately decoded.
[0068]
Specifically, the process shown in S20 may be inserted between S9 and S10 described in the above embodiment. In this case, since the processes in S1 to S19 are the same as those in the above-described embodiment, the detailed description thereof is omitted. However, the data decoded in S9 is stored, and in S20, the control circuit 3 causes the reading device body 1 to If the partial information code B to be decoded corresponding to the code number information and the reading object information stored in the memory 4 is decoded (YES), the partial information code B to be decoded is not decoded ( NO), the next partial information code B is decoded in S10. Therefore, when the partial information code B to be decoded is decoded, it is not necessary to decode all the partial information codes B included in the captured image data, and the reading can be completed quickly.
[0069]
FIGS. 14A and 14B show an example of the reading visual field region state.
When the partial information code B is read and decoded, the partial information code B cannot be read and decoded as long as the entire partial information code B is not included in the reading visual field area A. Therefore, as shown in FIG. 14, when the area of the reading visual field area A is extremely small, it may be difficult to put all the partial information codes B into the reading visual field area A (FIG. 14A). reference). In FIG. 14, among “1/5”, “5” indicates division number information, and “1” indicates a code number.
[0070]
Therefore, the control circuit 3 displays the information (for example, code number information, division number information, decoded data, etc.) of the decoded partial information code B after decoding the partial information code B included in the captured image data. Display on the unit 13. The control circuit 3 transmits the information to the computer 14 via the external interface unit 12, and the computer 14 displays this information on the display. FIG. 10 shows an example in which the code number information and the division number information are displayed on the display unit 13 and the display.
[0071]
That is, the reading apparatus main body 1 in step (3) will be described as an example. As shown in FIG. 14A, the code number “2, 3” of the partial information code B divided by the division number “5” is shown. , 4 "enters the reading visual field area A, the control circuit 3 can decode these partial information codes B, so that the code number" 2, 3, 4 "and the division Number information “5” is displayed on the display unit 13. Then, an operator who operates the reading device main body 1 understands that the partial information code B having the code number “1” does not enter the reading visual field region A by looking at the display unit 13. Therefore, when the operator causes the reading device main body 1 in step (3) to read the partial information code B having the code number “1”, the operator moves the position of the inspection object Y or checks the inspection line Z. , The partial information code B having the code number “1” can be decoded by the control circuit 3 of the reading apparatus main body 1. In this case, the control circuit 3 displays the code number information “1, 2, 3, 4” and the division number information “5” of the decoded partial information code B on the display unit 13.
[0072]
In this way, when all of the plurality of partial information codes B cannot be decoded, the code number of the decoded partial information code B is displayed on the display unit 13 and the division number information is displayed on the display unit 13. Therefore, since there is a notification that there is a partial information code B that has not been decoded, it is possible to notify the operator that at least a part of the partial information code B has not been decoded, thereby improving convenience. be able to.
[0073]
As shown in FIG. 10, when the computer 14 is configured to collectively manage the information (code number information, division number information) of each reading device body 1... 1, the computer 14 displays the information on the display. Therefore, it is possible to notify the operator of the computer 14 that at least a part of the partial information code B has not been decoded. In this case, the display unit 13 of each reading apparatus main body 1 may be provided as necessary.
[0074]
(Other embodiments)
The present invention is not limited to the embodiment described above, and can be expanded or modified as follows, for example.
You may apply to the optical information reader which reads one-dimensional code, such as a barcode.
[0075]
In the third embodiment, an embodiment in which three partial information codes B are searched is shown. However, four or more partial information codes may be searched.
Although an embodiment in which the information is displayed on the display unit 13 as a notification means has been described, a buzzer or the like may be sounded.
[0076]
Although the embodiment applied to a QR code or a data code has been shown, it may naturally be applied to other two-dimensional codes or a one-dimensional code such as a barcode.
[Brief description of the drawings]
FIG. 1 is a flowchart showing the operation of a first embodiment of the present invention.
[Fig. 2] Electrical configuration diagram
3A is a diagram showing an arrangement relationship of information codes with respect to a display space, and FIG. 3B is a diagram showing an arrangement relationship of partial information codes with respect to a display space.
FIG. 4 is a flowchart showing information code cutting processing;
FIGS. 5A and 5B are explanatory diagrams of partial information code cutting processing; FIG.
FIG. 6 is a view corresponding to FIG. 4 showing a second embodiment of the present invention.
FIG. 7 is an explanatory diagram of the evaluation criteria when extracting a specific pattern
FIG. 8 is a view corresponding to FIG. 1, showing a third embodiment of the present invention.
FIG. 9 is a diagram illustrating a method for estimating the position of a specific pattern of a partial information code.
FIG. 10 is a diagram showing a reading state of a partial information code in the fourth embodiment of the invention.
FIG. 11 is a diagram showing an example in which data is divided into partial information codes and displayed.
FIG. 12 is a diagram showing an example applied to a work line process
FIG. 13 is a flowchart showing additional processing.
FIGS. 14A and 14B are diagrams showing states of partial information codes included in a reading visual field region. FIGS.
[Explanation of symbols]
1 is a reader main body (optical information reader), 3 is a control circuit (decoding means, taking means), 4 is a memory (storage means), 10 is an optical sensor, 13 is a display unit (notification means), A Is a reading visual field area, B is a partial information code, B1 is an information pattern, and B2 is a positioning pattern (specific pattern).

Claims (8)

In a method of optically reading a plurality of partial information codes expressed for each partial data and displayed in a reading visual field area in a state where predetermined data is divided into partial data,
The partial information code is composed of an information pattern and a specific pattern serving as a position reference for specifying the position of the information pattern,
Capture image data including partial information code in the reading field area,
Detect specific patterns and their numbers from the captured image data,
Based on the number of detected specific patterns, determine the number of partial information codes included in the image data,
A method for reading optical information, comprising: collectively decoding the determined number of partial information codes included in captured image data using a specific pattern of the partial information code as a position reference . In a method of optically reading a plurality of partial information codes expressed for each partial data and displayed in a reading visual field area in a state where predetermined data is divided into partial data,
Capture image data including partial information code in the reading field area,
Partially decode the partial information code included in the captured image data ,
The decoding of the other partial information code is terminated when the partial information code to be decoded corresponding to the order information of the partial information code and the information to be read is successfully decoded. A method for reading optical information. The method for reading optical information according to claim 1 or 2,
The partial information code is composed of an information pattern and a plurality of specific patterns serving as a position reference for specifying the position of the information pattern,
Extracting a plurality of specific patterns from the captured image data;
Calculating a parameter such as a distance between a plurality of extracted specific patterns;
A step of performing arithmetic processing based on a predetermined evaluation arithmetic expression for the calculated parameter and determining whether or not a predetermined evaluation criterion is satisfied;
An optical information reading method comprising: deciphering the plurality of extracted specific patterns as position references of partial information codes when it is determined that the predetermined evaluation standard is satisfied. . The method for reading optical information according to any one of claims 1 to 3,
The partial information code is composed of an information pattern and a specific pattern serving as a position reference for specifying the position of the information pattern,
Detecting a plurality of specific patterns from the captured image data;
Detecting the entire outer shape of the partial information code included in the image data captured based on the plurality of detected specific patterns;
And a step of detecting a boundary between the partial information codes based on the entire outer shape of the partial information code being detected and a plurality of specific patterns. The method for reading optical information according to any one of claims 1 to 4,
The partial information code is composed of an information pattern and a specific pattern serving as a position reference for specifying the position of the information pattern,
The information indicated by the information patterns of the plurality of partial information codes includes division number information and rank information of the partial information codes,
After the partial information code of any of the plurality is decoded, the step of storing the position of the decoded partial information code, the division number information of the information pattern and the rank information in correspondence with each other;
If the decoding fails before all the partial information codes included in the captured image data are successfully decoded, the step of capturing the image data again;
Before re-decoding a plurality of partial information codes included in the re-captured image data, reading the stored partial information code position, information pattern division number information and order information,
A step of preferentially re-decoding the partial information code other than the position of the decoded partial information code. The method for reading optical information according to any one of claims 1 to 5,
The method for reading optical information, wherein the specific pattern is a geometric pattern or a light / dark pattern located at a predetermined location of a partial information code. The method for reading optical information according to any one of claims 1 to 6,
Each of the partial information codes includes an information pattern and a specific pattern serving as a position reference for specifying the position of the information pattern,
Detecting two specific patterns sequentially from the captured image data;
Measuring a distance between two detected specific patterns;
And a step of estimating a position of a partial information code not detected based on a measured distance interval or a specific pattern of the partial information code. 8. If a plurality of partial information codes cannot be decoded by the optical information reading method according to claim 1, information such as order information of the decoded partial information codes and reading object information is output. And steps to
And a step of notifying that there is a partial information code that has not been decoded .

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