JP6342739B2 - Paper sheet identification apparatus, paper sheet processing apparatus, and paper sheet identification method - Google Patents

Description

  The present invention relates to a paper sheet identification device that identifies identification information such as a serial number or a unique symbol printed on a paper sheet, and in particular, a paper sheet identification device that identifies identification information having different sizes of characters and symbols, The present invention relates to a paper sheet processing apparatus and a paper sheet identification method.

  Conventionally, there are various techniques related to this field. For example, Patent Document 1 describes a technique for correcting an identification number printed in a plurality of areas when a character is recognized with a digit shift by shifting each digit to confirm matching. .

JP 2012-174132 A

  In the technique of the above-mentioned Patent Document 1, the identification numbers printed in a plurality of areas are recognized in each area, and whether the characters match for each digit between the areas, and the confirmed characters are different from each other. In this case, the data is shifted one digit at a time in the upper digit direction or the lower digit direction, and it is confirmed whether or not they match. In this confirmation, when the identification information is misaligned due to dirt on the paper sheet or printing misalignment and the character is recognized, the misalignment can be corrected. However, if the identification number of the area to be shifted is correct and the identification number of the other area serving as the reference is misaligned, the identification information on the reference side itself is misaligned. The serial number cannot be recognized with correct correction. In addition, this technique is based on the premise that there are a plurality of areas where the identification number is printed, and there is a problem that it cannot be applied when the identification number is printed only at one location.

  The present invention has been made in view of the above, and is a paper sheet identification apparatus, a paper sheet processing apparatus, and a paper sheet identification method capable of correctly recognizing identification information attached to a paper sheet. The purpose is to provide.

  In order to solve the above-described problems and achieve the object, a paper sheet identification apparatus according to the present invention includes an imaging unit that captures identification information attached to a paper sheet, and an image captured by the imaging unit. A whole cutout unit that cuts out the entire area of identification information to be cut out, a digit cutout unit that cuts out a digit area of individual identification information from the whole area cut out by the whole cutout unit, and the digit cutout unit cut out The maximum size of one or both of the recognition unit for recognizing identification information of the region and the maximum size of the region cut out by the digit cutout unit or the maximum size of the identification information recognized by the recognition unit is determined in advance. A maximum size comparison unit that determines whether or not the maximum size is within the range, and when the maximum size comparison unit determines that the size is out of the range, the region is estimated again as the maximum size digit It is recognized by the recognition unit cut configured as a paper sheet recognition apparatus according to claim.

  Moreover, this invention is a paper sheet processing apparatus which has the said paper sheet identification device. Moreover, this invention is a paper sheet identification method performed with the said paper sheet identification apparatus.

  According to the present invention, it is possible to correctly recognize identification information attached to a paper sheet.

It is a figure which shows the physical structure of the paper sheet processing apparatus carrying a paper sheet identification device. It is a figure which shows the functional structure of the paper sheet identification device shown in FIG. It is a side view which shows the example of the operation | movement at the time of imaging of paper sheets. It is a figure which shows the external appearance of paper sheets. It is a figure which shows the example of the parameter table used for serial number recognition. It is a figure which shows the example from which the starting position and size of a search area | region in a table are read. It is a flowchart which shows the process sequence of a serial number recognition process (Example 1). It is a figure which shows the example of a character area by projection distribution. It is a figure which shows the example of the position and size of a cutting-out area | region estimated to be the character of the maximum size. It is a figure which shows the example from which the arrangement | sequence of the character size of each digit differs. It is a figure which shows the structural example of the parameter table in the case shown to FIG. 10A. It is a flowchart which shows the process sequence of a serial number recognition process (Example 2). It is a figure which shows the example of the process in S32 and S37 of FIG. It is a flowchart which shows the example which recognizes a character after the area is reset and cut out. It is a flowchart which shows the process sequence of digit shift discrimination | determination processing.

  Exemplary embodiments of a paper sheet identification apparatus, a paper sheet processing apparatus, and a paper sheet identification method according to the present invention will be described below in detail with reference to the accompanying drawings.

  FIG. 1 shows a physical configuration of a paper sheet processing apparatus such as an ATM (Automated Teller Machine) equipped with a paper sheet identification apparatus according to the present invention. As shown in FIG. 1, the sheet processing apparatus 1 includes an entrance / exit 2, a temporary storage unit 3, storage units 4 </ b> A, 4 </ b> B, 4 </ b> C, a recovery unit 5, a replenishment recovery unit 6, a cassette 7, And a paper sheet identification device 8.

  The entrance / exit 2 accepts paper sheets input by the operator and discharges paper sheets processed by the paper sheet processing apparatus 1. The temporary holding unit 3 temporarily holds the paper sheets that are input by the operator in the deposit process and received by the paper sheet identification device 8. The storage units 4A, 4B, and 4C store the paper sheets received by the paper sheet identification device 8. The collection unit 5 is a paper sheet that is not accepted by the paper sheet identification device 8 due to feeding from the temporary storage unit 3 or a paper sheet that is not accepted by the paper sheet identification device 8 due to feeding from the storage units 4A, 4B, and 4C. Storing things.

  The replenishing and collecting unit 6 stores paper sheets that have not been received by the paper sheet identification device 8 among the paper sheets fed from the cassette 7. The paper sheet identification device 8 determines the denomination of the conveyed paper sheet, recognizes the serial number, and determines authenticity. Each of the above parts is connected by a conveyance path 9, and the sheets are conveyed one by one through the conveyance path 9. Cases that the paper sheet identification device 8 does not accept include reasons such as feeding in an oblique direction and reasons for feeding, cases where the denomination could not be determined, and cases where it was determined that the bill was not a genuine note. .

  FIG. 2 is a diagram showing a functional configuration of the paper sheet identification device 8 shown in FIG. As shown in FIG. 2, the paper sheet identification device 8 functionally includes a control unit 20, a ROM 21, a RAM 22, an imaging unit 23, a denomination determination unit 24, a cutout unit 25, and various sensors. 26 and a character recognition unit 28.

  The control unit 20 controls the paper sheet identification device 8 as a whole. The ROM 21 is composed of, for example, a non-volatile memory and stores a parameter table including a control program used by the control unit 20 and a size of an area where a serial number is written for each denomination. Specific contents of the parameter table will be described later with reference to FIG. The RAM 22 is composed of, for example, a volatile memory, and stores variables used by the control unit 20, images captured by the imaging unit 23, and the like.

  The imaging unit 23 captures an image of a paper sheet. The denomination determining unit 24 determines the denomination and direction of the paper sheet. Note that the direction is the direction of the paper sheet, and includes four directions of a combination of left-right inversion and up-down inversion. The cutout unit 25 cuts out an area including the entire serial number (hereinafter referred to as an entire cutout area) from an image of the entire paper sheet, or a character area of each digit (hereinafter referred to as a cutout area). Cut out. The character recognition unit 28 recognizes characters in the entire cutout area or an image included in the cutout area. The various sensors 26 include, for example, a magnetic sensor and a thickness sensor, and are used for authenticating paper sheets. In the following, identification information such as a serial number attached to a paper sheet is simply described as a character, but various identification information that can be a serial number such as alphanumeric characters, symbols, codes, and the like are included.

  FIG. 3 is a side view illustrating an example of an operation at the time of imaging a paper sheet. As shown in FIG. 3, the paper sheet 30 is conveyed in the direction 42. The lamp 40A irradiates the entire upper surface of the paper sheet 30, and the line sensor 41A receives the light reflected from the paper sheet 30. The image data read from the line sensor 41A is for one line, but since the image is sequentially taken as the paper sheet 30 is conveyed, a two-dimensional image can be obtained as a result. Also on the lower surface of the paper sheet 30, a two-dimensional image can be obtained by the lamp 40B and the line sensor 41B in the same manner as the upper surface. In this figure, images of both sides of the paper are taken, but it may be configured to take only one side, and even if the transport direction and the position of the lamp and line sensor are reversed (upstream lamp, downstream The line sensor in the above may be reversed). Further, a two-dimensional image sensor may be used instead of the line sensor.

  FIG. 4 is a diagram showing the appearance of the paper sheet. As shown in FIG. 4, the serial number “AB123” is printed on the surface of the paper sheet 30. This serial number has the largest leftmost character, the smaller rightmost character, and the smallest rightmost character. For example, the serial numbers of banknotes in Singapore and Malaysia have different character sizes for each digit. In FIG. 4, the characters of each digit of the serial number are arranged in the horizontal direction, but the characters of each digit may be arranged in the vertical direction. Alternatively, the rightmost character may be the largest and the leftmost character may be the smallest. In FIG. 4, the combination of alphanumeric characters is used, but the serial number is not limited to alphanumeric characters and includes various identification information such as a unique symbol that can identify the paper sheet 30.

  In FIG. 4, the lower left corner of the paper sheet is set to the origin (0, 0) of the coordinate system, and there are parameters for cutting out the entire cutout area. The coordinates (X0, Y0) of the whole cutout area and the whole cutout area The horizontal size W0 and the vertical size H0 are stored in the ROM 21 for each denomination. Note that the lower left origin (0, 0) of the paper sheet is the origin of all subsequent coordinates. The parameters for cutting out the entire cutout region are called initial parameters.

FIG. 5 is a diagram illustrating an example of a parameter table used for serial number recognition. In the parameter table, for each digit of the printed serial number, the movement amount of the digit to the cutout area, the cutout area size, the character size and the character type of the digit are associated with each other in the X direction and the Y direction. It is remembered. In FIG. 5, since the serial number shown in FIG. 4 is 5 digits, the record of the parameter table is stored for 5 serial numbers of each digit.
By determining whether the maximum size of one or both of the maximum size of the cutout area or the recognized character size is within the predetermined maximum size range, the character size of that digit can be determined. Judge whether it is appropriate. However, in FIG. 5, the upper and lower size limit values in the parameter table are set in the vertical direction and the horizontal direction, but depending on the type of character font (for example, the vertical size is constant, the horizontal direction). When the size changes, the size in the horizontal direction) may be set. In FIG. 5, the movement amount of the serial number of the first digit to the cutout region in the X direction and the Y direction is the coordinates of the center position of the cutout region of the digit that recognizes the current serial number (for example, (X2, Y2)). And the difference from the coordinates (for example, X1, Y1) of the center position of the cut-out area of the digit for which the previous serial number is recognized. That is, when the center position of the segmented area of the digit whose serial number is recognized is obtained, the center position of the segmented area of the adjacent digit is obtained by adding the movement amount to the adjacent digit to the center position. Thereafter, it is repeated for all the digits.

  In addition, the sizes of the cutout areas in the X direction and the Y direction are respectively AW1 and AH1, and the upper limit of the character size lower limit in the X direction and the Y direction included in the cutout areas is CW1L or more and CW1H or less, and CH1L or more and CH1H or less, respectively. It is shown that. In addition, the character type indicates that it is an alphabetic character. The parameter table holds such a parameter set for each denomination, and is used with the coordinates inverted for the four directions. For the first digit, the movement amount from the coordinates (X0, Y0) at the center of the entire cutout area is registered. The amount of movement to the cutout area and the cutout area size in the table are read when the cutout area of the digit is cut out. For example, as shown in FIG. 6, X1-X0 and Y1-Y0, which are the movement amounts of the digit “A” having the largest character size at the left end, to the cutout area are the maximum from the coordinates of the central position of the whole cutout area. AW1 and AH1 are defined as the amount of movement of a digit including a character of a size to a cutout region, and the size of the cutout region cutout at that digit. The character size lower limit upper limit is an upper limit value and a lower limit value for confirming whether or not the size of the character is appropriate as a result of character recognition. When the upper limit value and the lower limit value are exceeded, it is determined that the character size is not appropriate. The character size is the size of a rectangle that encloses the line segment of the character that has been recognized, and is usually smaller than the size of the clipped area. The character type is also used when determining a target group for character recognition.

  In addition, the parameter table shown in FIG. 5 is arranged in the order of the character size. The reason why the parameter table is arranged in this order of the character size is that the digit having the largest size with the best recognition accuracy when characters are recognized one by one. This is because characters are recognized in order. The character size that determines the order may be the area of the cut-out character size (the product of the upper and lower limit of the character size in the X direction and the upper and lower limit of the character size in the Y direction), or the Y direction in which the difference in the size of each digit is easily understood. It may be a character size (that is, a vertical size in which the difference in size becomes significant). Next, processing (serial number recognition processing) performed by the paper sheet identification device 8 will be described.

  FIG. 7 is a flowchart showing a processing procedure of serial number recognition processing. In starting the following process, it is assumed that the denomination and direction have already been determined by denomination discrimination. That is, since the denomination is fixed, the parameter of the denomination in the parameter table can be referred to.

  As shown in FIG. 7, the cutout unit 25 first determines whether or not there is a setting of the center position of the cutout area of the digit (S10). Since it is not set at the beginning, the process proceeds to NO in S10, and the entire cutout area (for example, the dotted line area shown in FIG. 4) is cut out using the initial parameters stored in the ROM 21 (S11). The maximum size character is searched for in the cutout region cutout, the searched character is recognized, the character is fixed, and the character size is calculated (S12). As a search method of the maximum character, for example, a character included in the digit cutout region is cut out by a projection distribution as shown in FIG. 8, and the size (the character size in the X direction or the character size in the Y direction or their product) is extracted. There is a method for obtaining a character having the largest sum.

  In FIG. 8, the total value of the area SX of the pixel value VX when projected in the X direction and the area SY of the pixel value VY when projected in the Y direction is obtained. Is divided by the above-mentioned total value of characters having a predetermined reference size, a character size normalized with the reference character size can be obtained. For example, when the standard character size is defined as the character size of the smallest character written at the right end, and the total value for the character is divided by the total value for the character that can be recognized, The above total values for characters are all 1 or more. Among them, the character with the maximum total value can be determined as the character with the maximum size. Therefore, it is determined that the character having the maximum normalized character size is the maximum size character. In addition, when the character is misaligned, the area where the serial number is actually printed does not necessarily match the entire cutout area defined by the initial parameters. In that case, the character recognition unit 28 determines that the character included in the cutout area adjacent to the cutout area including the character recognized as the maximum size character is the character that should be recognized as the maximum size originally. For example, even if the character of the maximum size is recognized as “B” in FIG. 4, if the edge position of the pixel is at the position of “A” next to it, “A” is set as the character of the maximum size. to decide. Specific processing of this determination will be described later.

  Then, the character recognition unit 28 determines whether or not the maximum size character calculated by the cutout unit 25 has been recognized (S15), and determines that the maximum size character calculated by the cutout unit 25 has been recognized (S15). YES), it is further determined whether or not the character size is within a predetermined size range (S16). Whether or not the character size is within a predetermined size range is determined by whether or not the character size is within the upper limit of the character size lower limit in the X direction and Y direction of the parameter table shown in FIG. If the character recognition unit 28 determines that the character size is within the predetermined size range (S16; YES), the character recognition unit 28 corresponds to the recognized maximum size character and the character size read with reference to the parameter table. The center position of the cutout area to be stored is stored (S17). The center position of the cutout area is obtained as the center coordinates of each of EX1 and EX2 and EY1 and EY2 cut out by the projection distribution shown in FIG.

  On the other hand, when it is determined that the maximum size character calculated by the cutout unit 25 has not been recognized (S15; NO), or even when the character has been recognized, it is determined that the character size is not within the predetermined size range. (S16; NO), the process proceeds to S18 without storing the recognized character and the center position of the cutout area.

  The character recognition unit 28 determines whether or not the character of the maximum size digit in the parameter table (the first record in the table in the example shown in FIG. 5) has been determined (S18), and the maximum size digit in the parameter table. When it is determined that the character of the digit has been confirmed (S18; YES), the cutout unit 25 sets the center position of the cutout area of the next digit in the parameter table at the center position of the cutout area of the currently recognized digit stored in S17. The center position of the cutout area of the next digit is obtained by adding the amount of movement to, and stored together with the cutout area size of that digit (S19). The value obtained by adding half of the cutout area size from this center position is the upper end (right end) of the cutout area of that digit, and the value obtained by subtracting half of the cutout area size from this center position is the digit. This is the lower end (left end) of the cutout area.

  Then, the character recognition unit 28 determines whether or not all digits in the parameter table have been recognized (S22), and determines that all digits in the parameter table have not been recognized (S22; NO). Returning to S10, the subsequent processing is executed to sequentially recognize the character having the next maximum size from the remaining digits.

  As described above, when the character with the maximum size digit is determined, the center position of the cutout area of the next digit is determined in S19, so that the center position of the cutout area of the digit is set. It is determined (S10; YES), and the process proceeds to S13. The cutout unit 25 cuts out the set cutout area (S13), and calculates the character size included in the cutout cutout area (S14). Returning to the description, in S18, the character recognition unit 28 determines that the character of the maximum size character in the parameter table is not fixed (S18; NO), and further determines NO in S18 for the first time. It is determined whether or not (S20).

  When the serial number is printed without positional deviation, the maximum size character recognized in each processing from S10 to S17 is the maximum size character set in the parameter table. However, if the serial number is misaligned, the maximum size character recognized in the above processes does not necessarily become the maximum size character set in the parameter table. For this reason, the center position of the cutout area of the maximum size character and the cutout area size are estimated by performing processing described later.

  In S20, when the character recognition unit 28 determines NO in S18 for the first time (S20; YES), the character recognition unit 28 sets the center position and cutout area size of the cutout area estimated to be the maximum size character (S21). As the area of the maximum size character, a range as shown by a solid line in FIG. 9 is set when the end of the character string of the serial number has the maximum size. FIG. 9 shows a state in which “B” is recognized as the maximum size character in each process of S10 to S17, but a part of the character is recognized next to it. That is, although the maximum size character is recognized in S10 to S17, the maximum size character is not the maximum size character set in the parameter table in S18. If it is more than the range, it is recognized as a part of the character, the character including the pixel is determined to be the maximum size character, and the first record in the parameter table shown in FIG. The amount of movement to the cutout area and the cutout area size set in are read out and set as the cutout area of the maximum size character.

  FIG. 9 shows that the serial number “AB123” is shifted to the left from the initial position shown in FIG. 5 as a whole, and the deposit X such as dirt is present on the right side in the entire cutout region. . In the following, an example in which the sizes of all the digits are all different is described, but it is not necessary that the sizes of characters and symbols are all different, and includes cases where the sizes of some characters and symbols are different. Note that the area indicated by the dotted line in FIG. 9 corresponds to the entire cut-out area indicated by the dotted line in FIG. In this example, a part of the maximum size character (less than the right half) is included in the entire cutout area set by the initial parameters, while the other part (approximately the left half) is outside the range. Yes, printing misalignment has occurred. In this case, when “B” is recognized as the maximum size character, the character size of “B” is outside the range of the first digit character size in the table of FIG. 5 and within the second digit character size range. Therefore, the character recognition unit 28 determines that the character is the second digit character, reads the movement amount to the second digit cutout area of the table, and subtracts it from the center position of “B”. Thus, the coordinates of the center position of the first digit cutout area are obtained, and the coordinates and size (AW1, AH1) of the first digit center position are set as the maximum size cutout area. On the other hand, the character recognizing unit 28 determines that the character with the maximum character size in the parameter table has not been determined (S18; NO), and has not determined NO in S18 for the first time. If it is determined that this step is not the first time (S20; NO), it is determined as an error and the serial number recognition process is terminated. If the character recognition unit 28 determines that the character recognition of all the digits registered in the parameter table has been completed (S22; YES), it ends the serial number recognition process.

  Next, how the serial numbers shown in FIG. 9 are processed in the flowchart shown in FIG. 7 will be specifically described. Since there is no setting of the center position of the cutout region and the cutout region at the beginning of the process (S10; NO), the cutout unit 25 cuts out the entire cutout region indicated by the dotted line in FIG. 9 with reference to the initial parameters (S11). The character recognition unit 28 recognizes the character having the maximum size in the entire cutout region as “B” (S12, S15; YES), but the character size of the character recognized as the maximum size (in the X direction and the Y direction). Character size lower limit upper limit) is smaller than the character size of the first record in the parameter table (character size lower limit upper limit in the X direction and Y direction) (S16; NO). Not remembered.

  At this time, the character of the first record of the parameter table has not been determined (S18; NO), but since it is still the first process (S20; YES), it is shown in FIG. The solid line area is set as the cut-out area of the maximum size character (S21). At this stage, the recognition of all the digits has not been completed yet (S22; NO), and the center position and size of the cutout area have already been set (S10; YES). The cutout area is cut out (S13), and the characters included in the cutout area are recognized (S14). In this case, the character recognition unit 28 recognizes “A” on the left side of “B” (S15; YES), and the character size is within the predetermined range (S16; YES). And the center position of the cutout area corresponding to the character size is stored (S17).

  Since “A” is the maximum size character, the character of the first record of the parameter table is fixed (S18; YES), and the cutout unit 25 sets the center position of the cutout region of the next digit of the parameter table (S19). ). At this stage, since recognition of all the digits has not been completed yet, a cutout area including the set center position is cut out (S13), and characters included in the cutout area are recognized (S14). As described above, when the characters “A”, “B”, “1”, “2”, and “3” can be recognized, the character recognition of all digits is completed (S22; YES), and the serial number recognition processing is finished. To do.

  In the present embodiment, since such processing is performed, for example, as shown in FIG. 9, there is a case where the character “X” is recognized due to dirt or the like on the right side of “3” at the right end of the serial number. Even if there is a character, the serial number recognition process is terminated without recognizing the character, so even if the character is mistakenly recognized due to dirt or misprinting, each digit is recorded from the serial number printed in one place. It becomes possible to recognize the number correctly.

  Further, even when characters are recognized larger or smaller than the original character size due to dirt or printing misalignment, the error can be detected. Also, in order from the largest character to the smallest character, the position of the next character is determined based on the position of the larger character and the character recognition of each digit is performed. It is possible to obtain a reference, determine a cut-out area for the next character at a relative position from the reference position, and prevent dirt from being mistakenly recognized as a character. Furthermore, when the largest character size of the character size of each digit character recognized is not within the appropriate range, an area including an area where the clipping area has not yet been cut out (for example, a solid line portion in FIG. 9) Therefore, even if there is a printing misalignment, it is possible to prevent characters from being misaligned and to recognize characters and maintain the character recognition performance.

  In the above-described embodiments, the case has been described in which the leftmost or rightmost character is the largest and becomes smaller as it proceeds to the right or left digit. However, the character at either end is not necessarily the maximum size. Therefore, an example in which the arrangement of character sizes of each digit is different will be described with reference to FIGS. 10A and 10B. In the following, the center “1”, which is the third digit, is the largest, and the character size decreases as it goes to the end. In the parameter table, the third digit is registered as the first record. Since the character size of the second digit and the fourth digit is the same, it is registered as the next record. Furthermore, since the first digit and the fifth digit are the same, it is registered as the next record. Either the 2nd digit and the 4th digit, and the 1st digit and the 5th digit may be registered first, but if the digit with the smaller number of digits is registered first, the 3rd digit, the 2nd digit The fourth digit, the first digit, the fifth digit, and the fifth digit are registered. In addition, the parameter table at this time has a tree-like data configuration in the order of character size so as to decrease in order from the maximum size, as shown in FIG. 10B. Further, in order to obtain such a data structure on the tree, the parameter table shown in FIG. 5 includes the movement of the next digit number based on the center position of the cutout region of the digit having the maximum character size. It is necessary to obtain a plurality of amounts (for example, movement amounts to the second and fourth digit cutout regions) from the center position of the digit having the maximum character size.

  In the flowchart shown in FIG. 7, if digits having the same character size are registered in the plurality of parameter tables, the plurality of cutout areas are set (S19). For example, since the parameter table is configured on the tree shown in FIG. 10B, after recognizing the 3rd digit character which is the maximum size, the center position of the 2nd and 4th digit cutout regions and the cutout region size Is set (S19), the cutout area of the digit is cut out (S13), and the character is recognized (S14). By performing such processing, the serial number recognition process can be executed even when the character of the maximum size is not at the right end or the left end, and each digit of the serial number shifted in position can be recognized correctly. it can. Although the case where the maximum size character is in the middle has been described here, the present invention can be similarly applied regardless of the position of the maximum size character.

  Next, Example 2 will be described. In the second embodiment, since FIG. 1 to FIG. 10 are all the same except for FIG. 7, the same components are denoted by the same reference numerals and the description thereof is omitted. In FIG. 7, after cutting out characters one digit at a time and recognizing the cut out character, it is determined whether or not the digit of the character of the maximum size has been recognized, and then the next cutout region is determined. However, when there are a large number of digits in the serial number, it may take a long time to recognize characters one by one after recognizing the character of the maximum size. Therefore, in preparation for such a case, the second embodiment is different from the first embodiment in that the cut-out area of all the digits is cut out and the character of the maximum size and the digits are recognized at that stage. Furthermore, when there is a digit that has not been properly recognized including character size confirmation, the cutout area is reset and the character recognition process is executed again.

  With reference to FIG. 11, the processing procedure of the serial number recognition processing in the second embodiment will be described. As shown in FIG. 11, in the serial number recognition process according to the second embodiment, first, the cutout unit 25 cuts out the entire cutout region with reference to the initial parameters (S30). The character recognizing unit 28 cuts out the cutout region of each digit using a method such as the projection distribution shown in FIG. 8, recognizes the character included in the cutout region (S31), and checks the character size that can be recognized (S31). S32).

  The character recognition unit 28 determines whether or not the character of the maximum size among the checked character sizes is within the range of the character size upper and lower limits stored in the first record of the parameter table (S33). When it is determined that it is not within the range (S33; NO), similarly to the case of the first embodiment, the cutout region indicated by the solid line in FIG. In S34, the characters included in the cutout area are recognized (S35). On the other hand, if the character recognition unit 28 determines that the character of the maximum size is within the range (S33; YES), it proceeds to the next step.

  The character recognition unit 28 determines whether or not characters corresponding to the number of digits registered in the parameter table have been recognized (S36), and the number of digits registered in the parameter table (5 in the example shown in FIG. 5). If it is determined that only characters (digits) have been recognized (S36; YES), the serial number recognition process is terminated. On the other hand, if the character recognition unit 28 determines that the characters corresponding to the number of digits registered in the parameter table cannot be recognized (S36; NO), the character recognition unit 28 resets and cuts out the digit cutout region, and cuts out the cutout. The characters included in the area are recognized again (S37). Here, the resetting area to be reset is defined by the center position and the size of the clipping area of the corresponding digit in the parameter table, and in the same manner as in the first embodiment, a digit having a size larger than that digit is specified. The actual cutout area is relatively determined by the amount of movement of the digit from the center position of the cutout area where the character is recognized to the cutout area. That is, as in the case of the first embodiment, the center position of the cutout area of the corresponding digit and the center position of the cutout area of the next digit are obtained from the movement amount to the next digit, and the central position and the cutout area size of the digit are obtained. Set the cutout area. Of course, conversely, the cutout area may be determined by the amount of movement from the center position of the cutout area where a character with a size smaller than that digit is recognized to the cutout area of that digit.

  Here, the processing in S32 and S37 in FIG. 11 will be described with reference to FIG. In FIG. 12, it is assumed that the third digit from the left is soiled and the character originally “1” is recognized as “7”. Since the character size of “7” is larger than the character size of the corresponding digit in the parameter table, “7” is not stored (S32). As a result, the cutout area is reset (S37), but the cutout area as shown by the solid line in FIG. 12 of the size registered in the parameter table is reset with reference to the larger second digit “B”. In order to recognize the character that is cut out and included in the cut-out area, the character is recognized as “1”. By performing such processing, if the character size is not within the proper range, the area to be cut out is set again, and the cutout area is cut out with a size different from the size when erroneously recognized. Even if the character is recognized as another character having a different character size, the character can be properly recognized. Further, even when the number of digits is large, it is possible to quickly recognize characters of all digits.

  Next, Example 3 will be described. In Example 3, since FIG. 1 to FIG. 10 are all the same except for FIG. 7, the same components are denoted by the same reference numerals and the description thereof is omitted. In Examples 1 and 2, after recognizing the position of the maximum size character, other characters (smaller characters, characters that could not be recognized) were recognized. However, if the position of the maximum size character is known in advance, it takes extra time to recognize the maximum size character. Therefore, in preparation for such a case, in the following, it is predetermined that either the left end or the right end of the serial number is the maximum size, the character at the end is recognized first, and then the characters are recognized sequentially. explain. Note that processing for recognizing characters by cutting out the entire cutout region (S40, S41) and processing for resetting the cutout region (S45, S46) are the same as in the second embodiment.

  When the processing of S41 is executed, it is determined whether or not the recognized character size of the left or right digit is within the range of the character size of the parameter table (character size lower limit upper limit in the X direction and Y direction) (S42). ), If it is not within the range (S42; NO), the cutout region indicated by the solid line in FIG. 9 including the character adjacent to the left (or right) is cut out (S43) as in the case of the second embodiment (S43). ), The characters included in the cutout area are recognized (S44). On the other hand, if the character recognition unit 28 determines that the character of the maximum size is within the range (S42; YES), the process proceeds to S45. By performing such processing, even when the position of the character of the maximum size is determined in advance, it is possible to quickly recognize characters of all digits.

  Further, before recognizing the serial number as in the first to third embodiments, the serial number is determined to be misaligned. If a misalignment occurs, an error or that fact (which digit is misaligned) Or information on the position, denomination, character type, etc.) may be displayed on the display unit of the apparatus. In this case, the misalignment can be quickly grasped, and the misalignment can be easily recognized.

  For example, as shown in FIG. 14, the misalignment determination process may be executed before the processes shown in the first to third embodiments are executed. FIG. 14 is a flowchart showing a processing procedure for digit shift determination processing. As shown in FIG. 14, in the misalignment determination process, first, the size of characters included in the cutout region (the size of characters recognized by the character recognition unit 28) is compared with the character size stored in the parameter table. (S1401), it is determined whether or not the difference between the recognized character size and the stored character size is greater than or equal to a certain value for at least one character (including a case where the characters do not match each other) (S1402). If it is determined that the difference is greater than or equal to a certain value (S1402; Yes), error processing is executed (S1403). On the other hand, if it is determined that the difference is not greater than or equal to a certain value (S1402; No), the digit misalignment determination process ends without doing anything. The error process is a process of outputting error information including a position that is misaligned, a denomination, a character type, and a digit misalignment, and displaying the error information on a display unit such as a display. By performing such processing, it is possible to grasp the digit shift before the serial number recognition processing shown in the first to third embodiments. Further, by repeatedly executing such processing, it is possible to grasp how much digit deviation has occurred statistically. Further, it is possible to grasp the printing accuracy with respect to the serial number misalignment.

  Although not specifically described in the above-described embodiments, the paper sheets include various paper sheets with identification information such as serial numbers, such as gift certificates and securities, in addition to banknotes. . Further, the paper sheet identification device may not have the authenticity identification function. Furthermore, since character recognition itself is a general technique, details thereof will not be described here. However, character recognition may be performed by treating it as a binary image, or may be performed by treating it as a multi-value image. Further, character recognition may be performed by image template matching, or character recognition may be performed based on the length and direction of each line segment forming the character. Further, the imaging unit may be divided into an imaging unit that images the entire banknote and an imaging unit that images only the serial number region.

DESCRIPTION OF SYMBOLS 1 ... Paper sheet processing apparatus 2 ... Entrance / exit 3 ... Temporary storage part 4 ... Storage part 5 ... Collection part 6 ... Replenishment collection part 7 ... ··· Cassette 8 ··· Sheet identification device 9 ··· Transport path 20 ··· Control unit 21 ··· ROM
22 ... RAM
23 ... Imaging unit 24 ... Denomination determining unit 25 ... Cutting out unit 26 ... Various sensors 28 ... Character recognition unit 30 ... Paper sheets 40 ...・ Lamp 41 ・ ・ ・ ・ Line sensor.

Claims (7)

An imaging unit that captures the identification information attached to the paper sheet;
An overall cutout unit that cuts out the entire area of identification information included in the image captured by the imaging unit;
Among the entire area cut out by the whole cutout unit, a digit cutout unit that cuts out an area of digits of individual identification information, and
A recognition unit for recognizing identification information of an area cut out by the digit cutout unit;
Determine whether one or both of the maximum size of the area cut out by the digit cutout unit and the maximum size of the identification information recognized by the recognition unit is within a predetermined maximum size range A maximum size comparison unit,
The paper sheet identification apparatus, wherein when the maximum size comparison unit determines that the range is out of the range, a region estimated to be the maximum size digit is extracted again and recognized by the recognition unit. The digit cutout unit cuts out the identification information region of the maximum size from the identification information region of each digit as one identification information region,
The recognition unit identifies the next size of the identification information of the maximum size based on the position determined when the identification information region of the maximum size can be recognized and the region information including the identification information of other digits. Determine the position of the identification information area of each digit in order from the information area.
The paper sheet identification apparatus according to claim 1. The recognizing unit determines whether or not the size of the one identification information area cut out by the cutout unit is in a predetermined range, and a range in which the size of the one identification information area is predetermined If it is determined that the digit is not present, it is determined that the recognition result of the digit is invalid.
The paper sheet identification device according to claim 2. The cut-out unit cuts out the identification information area of each digit, and when there is a digit that the recognition unit cannot recognize in the cut-out identification information area of each digit, an area including identification information of a predetermined digit Based on, again cut out the identification information area of that digit,
The recognizing unit recognizes the identification information of the digit that has been cut out again.
The paper sheet identification device according to any one of claims 1 to 3, wherein In the recognition unit, a difference between the size of the identification information area of at least one digit out of the identification information area of each digit cut out by the cutout unit and a predetermined size of the identification information area of the digit is more than a certain value If it is
The paper sheet identification apparatus according to any one of claims 1 to 4, wherein   A paper sheet processing apparatus comprising the paper sheet identification apparatus according to claim 1. An imaging step of imaging the identification information attached to the paper sheet;
A whole cutout step of cutting out the entire area of the identification information included in the image taken in the imaging step;
Of the whole area cut out in the whole cutout step, a digit cutout step of cutting out a digit area of individual identification information, and
A recognition step for recognizing the identification information of the region cut out in the digit cutout step;
It is determined whether one or both of the maximum size of the area extracted in the digit extraction step and the maximum size of the identification information recognized in the recognition step is within a predetermined maximum size range. A maximum size comparison step to
A paper sheet identification method characterized in that, when it is determined that the maximum size comparison step is out of the range, an area estimated to be the maximum size digit is cut out again and recognized in the recognition step.

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