JP2006079571A - Printer print verification inspection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inspection device for high quality printing which allows the fine inspection of printed matters per page and detects and excludes defective printed matters. <P>SOLUTION: A prescribed print character which is printed on a form and different by pages or fixed is recognized and decoded and converted to a character code, and the character code is compared and collated with a character code printed to determine whether a printed matter is good or not, and a threshold of a recognition rate, recognition strength or the like is set to the inspection device beforehand when recognizing and decoding the print character, and an unreadable code is outputted in the case that it is not a threshold designated by recognizing and decoding image data of characters or the like read from a camera. Thus characters, bar codes, and graphics which are garbled because of having dirt or fading on a character itself or therearound are excluded as defects. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a print collation inspection of a printer device that sequentially prints different data or fixed data in units of pages on a printing paper at a high speed sequentially by a laser method and an ink jet method.

  The number of characters, hiragana, katakana, English, kanji, etc., as well as one-dimensional and two-dimensional barcodes, registered graphics, etc., are increasing at a high speed sequentially for each page using a laser method or an ink-jet method. In that case, there is a defect peculiar to the laser method or the ink jet method, dirt, fading, garbled characters, malfunction of the printer device, or print paper or print data set by the person on the printer device, what is the print data that should be printed originally A large amount of defective printed matter such as different data is printed, resulting in a decrease in business efficiency, leading to a loss of trust. The laser method has a defect that easily causes stains due to whitening, and the ink jet method has a tendency to cause stains due to ink drag. Normally used barcode scanners and OCR scanners simply read and decode and convert them to normal character codes, and there are stains and smudges on the print. Even dirt and smudges are read and the original print quality inspection is hardly inspected.

  Many printing papers have similar print patterns, and many mistakes occur when humans make visual judgments. Even when different printing papers are set in the printer and printed, or when the printing data is set incorrectly, the printing end It can only be found by visual inspection by sampling, and the printed paper is different from the original print paper and different from the original print data. Occurs frequently, increasing the printing cost and wasting resources.

  The printing speed of the printing apparatus is as high as 70 m / min to 300 m / min, and it is impossible for humans to visually detect defective printing during printing. In addition, it takes a lot of time and man-hours for humans to visually inspect each page after printing, resulting in a decrease in work efficiency and an increase in cost. An object of the present invention is to provide an inspection apparatus capable of finely inspecting printed matter for each page, and detecting and eliminating defective printed matter to perform high-quality printing.

  In order to solve the above-mentioned problem, when a barcode or character printed on paper is recognized and decoded and converted into a character code, it is read with a high resolution of 1 ×, 2 × or integer multiple according to the print density. . The reason for this is that laser-type or inkjet-type digital printer devices sometimes print with one dot. If the print density of the printed matter and the reading resolution of the camera are the same, one dot may be missing depending on the state of the printer device. This is because if the resolution is not read twice or an integral multiple, the characters become faint and fine inspection cannot be performed. The image data read from the camera usually uses a lot of multi-value data called gray scale such as 8 bits per dot, and therefore, when the page-unit image data is written and expanded in the memory, a huge amount of memory is required. Therefore, rather than searching for a specific position called a character recognition field from all the usual image data memories, only the position on the specified memory where the character should be recognized is extracted. Thus, the character recognition processing speed is increased.

  Next, when performing the above character recognition decoding, normal bar code scanners and OCR scanners give priority to reading, so even if there is some dirt or blur around the characters themselves, they are read and converted into some code. This is not the original print quality inspection. The inspection apparatus sets a threshold value such as a recognition rate or a recognition strength in advance when character recognition decoding is performed, and a code indicating that the read character cannot be read if it deviates from the specified threshold value, for example,? By outputting codes, etc., the recognition accuracy of printed characters, barcodes, graphics, etc. is close to some characters or graphics, but the inspection accuracy can be improved by eliminating suspicious characters or graphics. it can.

  Next, when recognizing and decoding one-dimensional barcodes, two-dimensional barcodes, registered graphics, etc. and normal characters, the recognition processing time per character is limited by a personal computer or a dedicated processing device. Therefore, in order to achieve consistency with the printing speed of the printing device, there are multiple inspection devices corresponding to the printing speed, and image data from the camera is sequentially distributed to multiple inspection devices in units of pages for parallel processing. By performing the above, inspection can be performed without being influenced by the printing speed of the printing apparatus.

  Next, the printing apparatus or printer apparatus often prints on continuous paper, and the printing position printed during paper conveyance is not always the same due to the meandering of the paper, and the printing position on the paper fluctuates both vertically and horizontally. Usually, the camera is fixed and the printed matter is read, so that when the paper meanders, the position called the field to be recognized of the printed matter also changes not vertically but vertically and horizontally. If this amount of fluctuation increases, characters, barcodes, figures, etc. that should be read from the field position that is originally specified by the camera are removed and cannot be read. Measures the amount of misalignment, that is, calculates the amount of vertical and horizontal fluctuations, and moves the specified amount of field in the camera image data, that is, by offsetting the XY offset, specifies the exact reading position even if there is paper meandering Therefore, the inspection accuracy can be improved.

  The feature of the present invention is different for each predetermined page printed on paper, or a fixed print character is recognized and decoded, converted into a character code, compared with the character code to be printed, and quality determination is performed. A threshold such as recognition rate or recognition strength is set in the inspection device in advance when performing recognition decoding, and if it is not the threshold specified in the recognition decoding of image data such as characters read from the camera, an unreadable code is output and characters It is an inspection device that can eliminate characters, barcodes, and figures that are garbled due to dirt or blur around itself or around the characters as defective.

  In addition, inspection can be performed regardless of digital printing apparatus or printing methods such as offset printing and gravure printing regardless of variable data and fixed data. The inspection result in the inspection apparatus is transferred to the server PC as a log, and if the log file is confirmed after the printing is completed, the quality of the printing result can be easily determined, and defective pages can be easily removed. In addition, when the inspection device detects a printing defect, it has a feature that a stop command is output to the printer device to stop printing and perform defect inspection in real time. Furthermore, by registering the print paper pattern format in advance, the operator compares the print paper set when actually printing with the pre-registered print paper and sounds an alarm if the paper is different. This is an inspection device that has the feature of preventing paper set mistakes and print data set mistakes.

  According to the printer print verification inspection apparatus of the present invention, it is possible to finely inspect printed results for printed matter in units of pages, and it is possible to identify and remove defective printed matter almost completely and to perform reliable and high-quality printing at high speed. A printer device with high performance can be provided.

  An embodiment of a printer print verification inspection apparatus of the present invention will be described with reference to FIGS. In the present embodiment, for example, a bill for a utility bill such as a telephone, electricity, gas, etc., a notification data for various individuals of a financial institution, etc. An inspection apparatus that inspects the print state of a printed matter that is printed by a printer apparatus of an ink jet system or an ink jet system and inspects whether a print result matches a print content that should be printed will be described. FIG. 1 is a diagram showing the basic principle of the entire inspection apparatus. Line sensor camera or area sensor camera 10. Distributor 15. A recognition decoder 20 for normal characters, one-dimensional barcodes, two-dimensional barcodes, graphics and the like. A character recognition engine 30 that compares the character code to be originally printed by the printer device with a normal character code obtained by recognizing and decoding image data read from the camera, and performs pass / fail judgment. A parameter 40 for transferring the recognition rate or the recognition strength as a threshold value to the recognition decoder. A server PC 50 that manages the parameters of the character recognition engine and the log data for each page from each character recognition engine. A control device 60 for the printer device to acquire character code data that should be printed in units of pages before inspection or after printing. The printer device 70 prints variable or fixed data in units of pages. Also, a control device 90 for transferring log data stored in the server PC 50 via communication such as Ethernet or via a medium such as a floppy. A controller 80 is provided for identifying a defective page found during inspection and rejecting or marking the page.

  Next, FIG. 2 is a basic configuration diagram and a connection configuration diagram of a control device called a distributor for controlling image data from the camera. This distributor has a function of specifying a character recognition field designated from camera image data to greatly reduce the memory amount and distributing image data reduced in units of pages to each character recognition engine. The printing density of the printer device is specified by the printer device. For example, if printing is performed at a resolution of 240 dpi, the reading resolution of the camera is read at a resolution of 480 dpi, which is equal to or twice as high as 480 dpi, or 960 dpi, which is equal to 4 times. Camera unit 100. A camera interface 110 for controlling transfer of image data from the camera. Toggle buffer memory # 1 120 corresponding to the reading speed of image data from the camera, and also toggle buffer memory # 2 130. A field buffer memory 140 for significantly extracting image data by specifying and extracting a character recognition field designated in advance from the read camera image data. A parameter interface 150 for transferring parameters for designating the XY offset movement amount, which is the amount of paper meandering, from the camera image data to the toggle buffer memory, operation parameters to the field buffer memory and the white balance controller; A white balance controller 160 for smoothing the lens aberration of the camera and the reading light source. A character recognition engine 170 for performing character recognition decoding from image data transferred from the field buffer memory and converting it into a normal character code. A server PC 180 for managing parameter transfer management to the distributor and threshold data for recognition decoding for the character recognition engine, character recognition result code log data from the character recognition engine, and the like. It has an Ethernet or parallel processing interface 190 which is a communication means for exchanging data such as a distributor, a character recognition engine, and a server PC.

  Next, FIG. 3 is a basic principle diagram of a distributor for extracting a character recognition field specified and specified from camera image data. Line sensor or area sensor camera 200. Image data 210 scanned and read by a camera. Represents a memory address called a pointer, which is a position in the field designated memory of each field of the camera image data 220. Represents the position information and size designated by the field from 220. 230. Field for recognizing the character designated by 230. Represents a memory reduction by 240. The memory size of the character recognition field extracted from 240 is represented by 250. The maximum printable range of a normal printing apparatus, high-speed laser printer, or inkjet printer is 17 inches wide and 17 inches long per page. If the reading resolution of the camera is 240 dpi vertically and horizontally, and the reading output of the camera is 8 bits (1 byte) per dot, which is multi-valued data, the camera dot is used to read 17 inches in the scanning direction (horizontal). The number needs 4096 dots, and the memory size corresponds to 4096 bytes per line. Further, the paper transport direction (vertical) corresponds to 4080 lines if 17 inches are read. A memory area size of 17 inches × 17 inches corresponds to approximately 16 megabytes per page. If this memory size is read and written as a memory called a normal RAM, an average of 50 ns per byte is required, and if it is 16 megabytes, approximately 800 ms are required per page. If the paper conveyance speed is set to 300 m / min (5 m / sec), the 17-inch paper conveyance vertical passage time is 864 ms, and it can be seen that the limit of writing image data from the camera is almost the limit. Since the paper is sequentially conveyed, the next 17-inch reading is started, and therefore, if there is no memory for at least two pages, the next camera image data is overwritten, so toggle buffer memory # 1 120, # in FIG. 130 which is 2 is required. In other words, if one of the memories is being written, it is necessary to prevent the camera image data for each page from being missed, which is used for reading and sequentially conveyed. Taking FIG. 3 as an example, if 210 indicates the relationship between the camera scan and the memory and 220 indicates the two fields for character recognition and decoding, the 16 megabyte toggle buffer memory of the page unit memory indicates the field position and size therein. Field buffer memory 240 in which 230 is extracted from page unit memory 220 and rearranged. In this example, the actual memory size of the two fields is 954 horizontal dots, that is, 954 bytes and 572 vertical lines, so the memory size 250 corresponds to about 0.54 megabytes and is reduced to 1/30 of the original 16 megabytes. That's right. In other words, instead of looking for a field for character recognition in the page unit memory that is camera image data, character recognition decoding is performed by rearranging only the specified character recognition field from the page unit memory and reducing the memory size. Therefore, the processing time required for the processing can be greatly reduced, and the speed of the character recognition processing can be increased. Then, the position of the print reference mark is read by the camera interface 110 from the camera image data in page units, and the amount of fluctuation up and down and left and right from the original predetermined print reference position is calculated. When the camera image data is transferred to 130, which is 2, the XY offset amount, which is the calculated fluctuation amount, is transferred as the image data that has been moved, so that the image data that has a meandering paper and deviates from the original position is originally predetermined. By returning to the position, the reading position accuracy is guaranteed, and the recognition accuracy when recognizing characters can be remarkably improved.

  Next, FIG. 4 shows the difference in the page unit forms printed by the printer device, and shows that the white portion in the page unit form is identified and the stain is detected 300 and 310. As an example, 300 is a telephone bill, and 310 is an electricity bill. 320 shows the printing order and printing direction of the printer device. Usually, a printer device often prints on a continuous paper using roll paper or fanfold paper with perforations, and a print cue mark is printed as a page unit. In other words, when the telephone bill 300 and the electricity bill 310 in FIG. 4 are one page, different data or the same data is printed in the same picture format for each cue mark. Each form is usually printed with a unique printed pattern such as a company mark in advance, or the printed pattern is variable or fixed on white paper on which nothing is printed, such as on-demand printing that has increased in recent years. In many cases, information is printed. In this case, a company mark or the like of a unique print pattern is read and coded by a camera and registered. If the paper is set incorrectly, the company mark, which is a unique print pattern for each page of the loaded paper, is read by the camera, which is different from the company mark registered in advance. By ringing, it is possible to inform the user that a mistake has occurred and minimize waste of paper. If the print data is set incorrectly and printed, the print data that should be printed after page-by-page printing is compared with the read data to make a pass / fail judgment. If there is no character specification or the specified format is different from the specified format such as there is a barcode even though it is character specification, continuous reading errors occur. In this case as well, if you inform the operator with a light and buzzer as above Similarly, waste of paper can be eliminated. Also, the normal form has a white portion that is neither printed nor printed. The white portion can be detected by designating a plurality of areas as well as the size of the stain.

  Next, FIG. 5 is an overall configuration diagram of the printer print collation inspection apparatus. Line sensor camera or area sensor camera 400. Distributor 410 for significantly reducing memory by extracting only the designated character recognition field from the camera image data. A plurality of character recognition engines 420 and 430 for inspecting in units of pages corresponding to the printing speed. A server that controls the specification of character recognition fields, threshold parameters for recognition decoding, reading log data control for each page from the character recognition engine, and storage of print character codes that should be printed in advance or after printing in page units. PC440. A printer management host 450 that controls the printer device and manages print data to be originally printed. It has an Ethernet communication means or a parallel processing system interface 460 that controls the exchange of log data and parameter data between the devices.

  An example of the above-described printer print collation inspection apparatus according to the embodiment of the present invention will be described. If the printed picture used for printing read from the camera 400 in FIG. 5 before the inspection is, for example, the telephone bill 300 and the electricity bill payment handling slip 310 in FIG. 4, the company shows the characteristics of each company. The mark portion is registered and stored in each memory of character recognition engine # 1 420 and character recognition engine # 2 430 in FIG. The company mark or the like indicating the characteristics of the paper in the registered printed pattern is given a number or name as a form format, and communication such as Ethernet connected to each character recognition engine on the hard disk of the server PC 440 in FIG. The transfer management is stored through the means. As a matter of course, the form format can register and store paper types to be used. Here, the form format stored and registered in the server PC 440 in FIG. 5 is called from the hard disk, and the reading field and the dirt to be recognized for the print format of the telephone bill 300 or the electricity bill payment handling form 310 in FIG. A stain inspection area for detection, a stain detection size, and threshold data for character recognition decoding are designated. In the dirt inspection area, it is possible to specify and specify a plurality of white portions around the area other than the character recognition field. The server PC 440 in FIG. 5 registers and stores the specified character recognition field, dirt inspection area data, and character recognition decode threshold data as form format file data on the hard disk of the same server PC 440 in FIG. A paper type is selected and transferred to 420 and 430 which are character recognition engines # 1 and # 2 connected to the server PC 440 in FIG. 5 via communication means such as Ethernet. The transferred data is registered and stored in a memory provided in each character recognition engine as a form format for identifying a form type such as a company mark, character recognition and dirt inspection. The address specified and specified in the form identification field such as the company mark, the character recognition field, and the dirt inspection field is transferred and stored in the distributor 410 in FIG. 5 as the address pointer 230 in FIG. At the same time, the threshold parameter and the dirt inspection parameter which are the recognition rate or the recognition strength are transferred and stored in 420 and 430 which are the character recognition engines # 1 and # 2 in FIG. Here, the operator sets paper in the printer device to start printing, and at the same time, makes the inspection device usable. At the same time, the character code for each page to be printed is transferred from the printer management host in FIG. 5 in advance or after printing in page units to the server PC 440 in FIG. 5 or 420 as the character recognition engine # 1 and 430 as the character recognition engine # 2. Keep it. When the paper is conveyed and the print queue mark of the first page is read and input by a sensor equipped in the printer device as indicated by 320 indicating the printing state in FIG. 4, the reading of the camera is started and the image data is sequentially transferred. 2 is input to the toggle buffer memories # 1 and # 2 120 and 130 via the camera interface 110 from the camera 100 in FIG. 2 in a predetermined unit that takes into account the XY offset amount that is the paper meandering amount. Transfer the changed camera image data to. Company image identification field and character recognition field indicating the characteristics of the paper already set by the server PC 440 of FIG. 5 and transferred via the parameter interface 150 of FIG. 2 from the camera image data transferred alternately from the toggle buffer memory. Only a specific position is extracted from the dirt inspection field for detecting dirt and transferred to the field buffer memory 140 for storage. Transferred sequentially from the field buffer memory 140 in which the memory amount of each transferred page unit is reduced to the character recognition engines 420 and 430 of FIG. 5 in page units, and this character recognition engine matches forms such as company marks. Checking the consistency between the character code to be printed obtained in advance or after printing in page units and the character code decoded from the camera image data specified in the character recognition field and converted into the normal code and specified Contamination inspection in the contamination inspection field is sequentially performed in units of pages and mismatches, and regardless of the coincidence, log data as reading inspection results in units of pages from each character recognition engine to the server PC via communication means such as Ethernet. Server as inspection result log data from transfer to printing completion And stores it in the C of the hard disk.

  Next, the form format such as the company mark, which is the form format, or the character code to be printed obtained in advance or after page-by-page printing, and the normal character code that has been recognized and decoded by the reading field to the image data from the camera, Mismatch or unreadable? When there is a discrepancy due to the code, or when a stain larger than the specified size in the stain inspection field is detected, the light is turned on and the operator is notified by the buzzer sounding to minimize waste of paper. Since continuous printing is often used in normal printing, it goes without saying that it may be a form format consistency inspection for inspecting the consistency of a pattern format such as a company mark of about one page or two pages from the start of inspection. However, if the sheet is a cut sheet, the operator may mistakenly set a different form in the bundle, so it is possible to specify whether the total number or the set number is set in the parameter setting of the server PC.

  According to the printer print collation inspection apparatus of the present invention, it is possible to perform a fine inspection of a print result for a printed product in units of pages, and it is possible to almost completely identify and remove a defective printed material, a paper set difference, a print data set error, etc. It is possible to provide a highly reliable printed matter that can prevent an erroneous operation by a human and can perform accurate and high-quality printing at high speed.

  In the printer print verification inspection apparatus according to the embodiment of the present invention, a character code obtained by converting a one-dimensional bar code, a normal character, a two-dimensional bar code, a figure or the like from image data from a camera by character recognition decoding and the printer device in advance. Or, it is a basic principle diagram of a character recognition engine that determines the quality of a character code by comparing and collating it with a character code acquired after page unit printing.   When writing image data from the camera to the toggle buffer memory in units of pages, an XY offset for aligning the read field to be recognized by paper meandering, and for reducing the memory by identifying the read field from the toggle buffer memory It is a basic principle figure of a distributor.   It is a basic operation principle diagram for reducing the XY offset and memory of the distributor.   FIG. 4 is a diagram illustrating a type of a form printed by a printer device, a difference between forms, and a printing direction.   1 is a diagram showing an overall configuration of a printer print verification inspection apparatus according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... High-resolution camera, 15 ... Distributor, 20 ... Character recognition decoder, 30 ... Character code comparison collation pass / fail judgment memory, 40 ... Character recognition decoding judgment threshold memory, 50 ... Character Code comparison verification result log data management server PC 60 ... print character code storage control device 70 ... printer device 80 ... defective page removal device 90 ... inspection result log data transfer device 100 ..High resolution camera, 110... Camera interface, 120... Toggle buffer memory # 1, 130... Toggle buffer memory # 2, 140... Field buffer memory, 150. ..White balance controller, 170 ... Character recognition engine, 180 ... Sir -PC, 190 ... Communication means such as Ethernet, 200 ... High-resolution camera, 210 ... Camera image data toggle buffer memory write state diagram, 220 ... Toggle buffer memory XY offset and read field state diagram 230 ... Toggle buffer memory reading field position quantification state diagram, 240 ... Field buffer memory amount reduction state diagram, 250 ... Field buffer memory amount reduction quantification state diagram, 300 ... Form format reference diagram 310 ... Form format reference diagram, 320 ... Printing direction diagram, 400 ... High resolution camera, 410 ... Distributor, 420 ... Character recognition engine # 1, 430 ... Character Recognition engine # 2, 440 ... Server PC, 45 ... printer management host, communication means, such as 460 ... Ethernet.

Claims (6)

  Ordinary characters, bar codes, graphics, etc., which are printed at a high speed sequentially with different print data for each page or fixed print data for each page in a printer or printing device, are read and decoded with a line sensor camera or area sensor camera. Means for converting to the character code, means for comparing and comparing the read and converted character code with the character code to be printed that has been acquired in advance or after printing, and log data that is the result of the pass / fail determination An inspection apparatus having means for storing and easily searching for a defective page, and means for marking or rejecting a detected defective page.   Using the amount of memory of all image data by specifying the area to extract the necessary part from the image data read by the line sensor camera or area sensor camera from the print data printed in units of pages in the inspection device and to identify and decode the character An inspection apparatus having means capable of speeding up the character recognition processing by reducing the processing time for performing the character recognition processing by converting the memory amount to the minimum necessary amount without doing so.   Inspect the area other than the printing area by designating the white area inspection area other than the printing position of characters, barcodes, graphics, etc. that should be printed within the inspection area specified in page units in the inspection device. An inspection apparatus having means capable of detecting a stain of a specified size or more that is a printing defect.   In the recognition of characters, barcodes, figures, etc. read in page units in the inspection device, a threshold is set for the recognition rate or recognition strength instead of converting the read characters into some character code. An inspection apparatus having means for outputting a code that cannot be recognized except for the recognition rate or the recognition strength.   In the inspection apparatus, the page unit reference mark on the paper conveyed by the printing device or the printer device is read by a camera, the reference mark position is measured in page unit, and the amount of paper meandering that is a fluctuation amount from the original position An inspection apparatus having means for automatically correcting an accurate reading position by moving a meandering amount obtained by measuring the positions of characters, barcodes, figures, and the like to be recognized by calculating.   In the above inspection device, the position of characters, barcodes, graphics, etc. to be printed in a predetermined page unit and the pattern on the printing paper are specified and registered in advance, so that the paper is incorrectly set in the printer device at the time of actual printing. An inspection apparatus having means for detecting a difference in print data set by a human.

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