JP2008005380A - Image processor and image acquisition method for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image processor and an image acquisition method for the same, the apparatus and the method providing prescribed image data by the main scanning performed by the image processor, even when a threshold for binarizing image data by prescanning cannot be determined. <P>SOLUTION: A complex processor 2 generates two-gradation image data, by scanning an image of a check 100 with a command from a host computer; however, even when a threshold for generating the two-gradation image data cannot be determined, shifts the present processing to a succeeding processing step, without having to execute error processings by the host computer 3. Processing steps include processing operation (STs 111 to 112) for obtaining image data of 256 gradations, processing operation (STs 121 to 124) for obtaining two-gradation image data, by executing binarizing processing after the sharpening processing of a main-scanned image and processing operation (STs 131 to 133) for obtaining two-gradation image data by using a preset threshold, and which processing operation is to be executed can be set. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an image acquisition method of an image processing apparatus that scans the surface of a medium to be read according to a command from a host computer, performs predetermined image processing on acquired image data, and transfers the image data to a host computer.

  In electronic payment using a check, payment processing is performed between a host computer of a store and a server of a payment institution via a communication line based on information such as an account number written on the check. For this reason, there is no need to bring the check drawn out by the customer to the clearing house, so the necessary book and endorsement are made and returned to the customer. However, if the check is returned to the customer as it is, there is no evidence in the store that the payment was made with the check. Therefore, the store scans the image of the check before returning it, and stores the obtained image data as proof of payment.

  The check scan is performed by an image processing device connected to a host computer. The image processing apparatus performs binarization processing that converts high gradation image data obtained by scanning into two gradation image data of black and white, and then transfers the data to the host computer. The image processing apparatus performs the binarization process in order to reduce the data capacity of the image data. In the store host computer to which the image data is transferred, a large number of check image data used by many customers are stored. This is because of the need to store for a long time.

In order to perform binarization processing, the image processing apparatus first pre-scans a part of a check and determines a threshold value from the obtained information. Next, a main scan is performed, and the obtained image data is converted to two-tone image data based on this threshold value. However, some checks are too dark to determine the threshold. Therefore, the image processing apparatus once transmits a result (whether there is a pre-scan error) whether or not the threshold value can be determined by pre-scan to the host computer, and the host computer that received the notification has a pre-scan error. In this case, necessary error processing is performed, and then a main scan command is issued to the image processing apparatus (see Patent Documents 1 and 2).
FIG. 5 of JP2003-150799A FIG. 4 of Japanese Patent Laid-Open No. 2003-150800

  However, the host computer checks whether there is a pre-scan error transmitted from the image processing apparatus, performs necessary error processing if a pre-scan error has occurred, and then the host computer connects to the image processing apparatus. In an image acquisition method in which a scan command is transmitted, there are problems that transactions between the host computer and the image processing apparatus increase and application error handling in the host computer becomes complicated.

  In view of the above, the present invention has been made in view of the above points. Even when the threshold value cannot be determined by prescanning, the main scan is performed without performing the prescan error processing by the host computer, and the desired image processing is performed The object is to propose an image acquisition method of an image processing apparatus for transferring image data to a host computer. Another object of the present invention is to propose an image processing apparatus that reads an image by the image acquisition method.

  In order to solve the above-described problem, an image acquisition method for an image processing apparatus according to the present invention includes a receiving step of receiving a scan start command from a host computer, and at least one on the surface of a medium to be read when the scan start command is received. The first image data is binarized on the basis of the pre-scanning step of scanning the area of the portion and acquiring the first image data with a gradation higher than two gradations, and the obtained first image data A threshold value determining step for determining a threshold value for scanning, a main scan step for scanning at least a part of the surface of the medium and acquiring second image data with a gradation higher than two gradations, and the threshold determination Two-tone image data for generating two-tone image data by binarizing the second image data based on the threshold value when the threshold value is determined in the process The second image data or the second image data when the threshold value cannot be determined in the generating step, the image data transmitting step for transmitting the two-tone image data to the host computer, and the threshold value determining step. Including a processing step of adding error information indicating that the threshold value cannot be determined to third image data obtained by performing predetermined image processing on the image data, and transmitting the error information to the host computer. To do.

  According to the present invention, the image processing apparatus moves to the next processing step even when the threshold value cannot be determined by the threshold value determination step, and performs predetermined image processing on the obtained second image data or second image data. The third image data obtained by applying is transmitted to the host computer. Even if a pre-scan error occurs, the host computer moves to the next processing step without performing the error processing. Therefore, the host computer scans the error from the pre-scan error occurrence and the main scan from the occurrence of the pre-scan error. There is no transaction processing during the transition to the process. Therefore, it is possible to simplify error handling of applications installed in the host computer.

  Even when the threshold value cannot be determined, the second image data or the third image data is transmitted to the host computer, so that the host computer can always acquire an image as a result of the scan start command. Further, since error information is added to the image data transmitted to the host computer, it is convenient when the host computer uses the image data.

  Here, when the second image data having a higher gradation than the two gradations obtained in the main scanning process is transmitted to the host computer, the second image data is generated when the threshold is determined. The data capacity is large compared to the two-tone image data, but there is an advantage that the information on the surface of the medium that may be lost when binarized is retained without being lost. .

  In the present invention, the third image data is sharpened on the second image data to generate sharp image data, and the sharp image data is binarized based on a preset threshold value. The obtained second two-tone image data can be obtained. Since the second image data obtained in the main scanning process is subjected to a sharpening process for emphasizing the outline of characters and symbols written on the surface of the medium, a binarization process is performed. The second two-tone image data can be generated without losing information that may be lost when the binarization process is performed. In addition, since the third image data (second two-tone image data) is two-tone image data, the data volume of the image data transmitted to the host computer is small and suitable for storage.

In the present invention, the third image data may be third two-tone image data obtained by binarizing the second image data based on a preset threshold value. In this processing operation, the second image data is binarized with a preset threshold value to generate third two-tone image data, so that information on the medium surface is lost during the binarization process. There is a possibility of it. However, the transaction can be terminated in response to a scan start command from the host computer. In addition, since the third image data (third two-tone image data) is two-tone image data, the data capacity of the image data transmitted to the host computer is small and suitable for storage.

Further, the present invention can include a setting step for setting which of the following (1) to (3) the processing operation in the processing step is performed based on a setting command from the host computer. .
(1) Processing operation for adding the error information to the second image data and transmitting it to the host computer. (2) As the third image data, sharpening processing is performed on the second image data to generate sharp image data. Then, the second two-tone image data obtained by binarizing the sharp image data based on a preset threshold value is adopted, and the error information is added to the second gradation image data to the host computer. Processing operation to be transmitted (3) As the third image data, third two-tone image data obtained by binarizing the second image data based on a preset threshold value is adopted. , Processing operation to which the error information is added and transmitted to the host computer

  According to the present invention, the processing operation in the processing step when the threshold value cannot be determined by the threshold determination step is set as (1) to (3), and which processing operation is performed depends on the host computer. Is set based on the setting command from. In the host computer, it is possible to select in advance the processing operation to be shifted when the threshold value cannot be determined by the setting command, so that it is possible to easily construct an application mounted on the host computer.

  Here, the setting command may be received in the receiving step. In this way, it is possible to set which processing operation is to be performed together with the check image scan start command when the threshold value cannot be determined by the threshold value determination step. Since the processing operation after a scan error occurs can be set dynamically, a flexible application can be constructed.

  In the present invention, it is preferable that the first image data and the second image data are image data of 256 gradations.

  In the present invention, the medium to be read can be a check.

  Next, the image treatment apparatus of the present invention is characterized in that the reading operation of the surface of the medium to be read is performed by the above-described image acquisition method.

  According to the present invention, the image processing apparatus moves to the next processing step even when the threshold value cannot be determined by the threshold value determination step, and performs predetermined image processing on the obtained second image data or second image data. The third image data obtained by applying is transmitted to the host computer. Even if a pre-scan error occurs, the host computer moves to the next processing step without performing the error processing. Therefore, the host computer scans the error from the pre-scan error occurrence and the main scan from the occurrence of the pre-scan error. There is no transaction processing during the transition to the process. Therefore, it is possible to simplify error handling of applications installed in the host computer.

  Even when the threshold value cannot be determined, the second image data or the third image data is transmitted to the host computer, so that the host computer can always acquire an image as a result of the scan start command. Further, since error information is added to the image data transmitted to the host computer, it is convenient when the host computer uses the image data.

(Overall configuration of check payment system)
Embodiments of a composite processing apparatus to which the present invention is applied will be described below with reference to the drawings. FIG. 1 is an external view of a check settlement system including a composite processing apparatus according to an embodiment of the present invention. FIG. 2 is a block diagram of the check settlement system of this embodiment. FIG. 3 is a schematic cross-sectional view showing a configuration around the check conveyance path of the combined processing apparatus shown in FIG.

  As shown in FIGS. 1 and 2, the check settlement system 1 used for the check processing of this example includes a composite processing device 2 and a register device (host computer) 3. The composite processing apparatus 2 is connected to the host computer 3 with a cable and is installed at the accounting counter of the store. The host computer 3 is connected to the settlement institution server 4 via a communication line.

  The composite processing apparatus 2 has a substantially cubic shape with a resin casing, and has an insertion slot 11 for inserting a check 100 for electronic settlement on the front side portion. As shown in FIG. 3, the check 100 inserted from the insertion slot 11 is conveyed from the lower side to the upper side along the J-shaped conveyance path 12 in the composite processing apparatus 2. During the conveyance, necessary processing is performed on the check 100 according to a command from the host computer 3, and then the sheet is discharged from the discharge port 13 formed in the upper surface portion. A scanner unit 40 that scans the check 100 immediately before being discharged is located near the discharge port of the conveyance path. A roll paper discharge port 14 is formed on the rear side of the discharge port 13, and an accounting statement, an agreement necessary for electronic settlement, etc. are provided on the roll paper (not shown) stored in the rear side portion of the housing. After printing, it is discharged from here.

  The host computer 3 includes a panel unit 5, a transaction display unit 6, a storage device 7, and a credit card reader unit 8, which also serve as an input device for a store clerk to input an amount and an electronic payment instruction. Since the host computer 3 is connected to the settlement institution server 4 via a communication line, the settlement information such as the account number described in the check 100 is inquired to the settlement institution server 4 to check the validity of the issued check 100. Sex can be confirmed.

  A block configuration of the check settlement system 1 and a configuration of each processing unit will be described with reference to FIGS. The composite processing apparatus 2 includes a central processing unit (CPU) 20 and a memory 21 for storing basic software and setting information for controlling the composite processing apparatus 2, image data read by a scanner, and the like. The CPU 20 and the CPU 30 of the host computer 3 are connected so that commands and data can be transmitted and received. The CPU 20 controls the magnetic ink character reading unit 50, the end printing unit 60, the front page printing unit 65, the scanner unit 40, the roll paper printing unit 70, the check transport unit 80, and the check position detection unit 90 according to commands from the host computer 3. Then, necessary processing is performed while conveying the check 100 inserted from the insertion slot 11.

  The magnetic ink character reading unit 50 uses the magnetic ink characters printed in the MICR (Magnetic Ink Character Recognition) recording area 101 (see FIG. 1) in the lowermost column of the inserted check 100 to make payment of the account number. A MICR head 51 for reading information is provided, and is arranged at a position close to the insertion slot 11. The read settlement information is transmitted from the CPU 20 to the host computer 3.

The endorsement printing unit 60 prints items such as the identification number, date, amount of money used, etc. The front cover printing unit 65 prints matters such as the payee, date, and amount when there is no front cover on the drawn check 100. Each printing unit includes dot impact type print heads 61 and 66. The print head 61 of the endorsement printing unit 60 is arranged on the upstream side of the transport path, and the print head 66 of the cover printing unit 65 is arranged on the downstream side. . The print head 61 of the endorsement print unit and the print head 66 of the endorse print unit are arranged on opposite sides of the conveyance path 12 so that the front and back surfaces of the check 100 can be printed. Platens 62 and 67 are disposed on the opposite sides of the print heads 61 and 66 with the conveyance path 12 therebetween. As the print heads 61 and 66, other types such as an ink jet type can be used.

  The scanner unit 40 reads the surface of the check 100 on which the end document and the front cover are printed and the electronic payment is completed. A check 100 transported through the transport path 12 toward the discharge port 13 is scanned by a contact image sensor 41 attached in the vicinity of the discharge port 13. On the opposite side across the conveyance path 12, a feed roller 42 that conveys the check 100 in close contact with the image sensor is disposed. The scanner unit 40 first pre-scans a predetermined area in the rear portion of the MICR recording area 101 of the check 100 with 256 gradations. Then, a threshold for binarizing the image data is determined from the luminance distribution of the obtained image data (first image data). Further, the entire surface of the check 100 is scanned to obtain 256-gradation image data (second image data). When the threshold value is determined, the 256 gradation image data is binarized based on the threshold value to generate two gradation image data (first two gradation image data). The generated two-tone image data is transmitted to the host computer 3 together with the attribute information. When the threshold value is not determined, image data acquired by performing a predetermined processing operation described later is transmitted to the host computer.

  The roll paper printing unit 70 is provided with a thermal line type print head (not shown), and prints an accounting statement, a consent for electronic payment of a check, etc. from the roll paper outlet 14. Discharge. Further, the roll paper discharge port 14 is provided with an auto cutter (not shown), and when the roll paper for which necessary printing is completed is discharged, the roll paper is cut at an appropriate position.

  The check conveyance unit 80 conveys the check 100 inserted into the insertion port 11 along the conveyance path 12 to the discharge port. A pair of transport rollers 81 and 82 sandwiching the check 100 is provided, and the check 100 is transported by driving the transport rollers. Since the transport rollers 81 and 82 are rotationally controlled in both forward and reverse directions, the check 100 is transported in both the front and rear directions.

  The check position detection unit 90 detects that the check 100 conveyed by the sensors 91, 92, and 93 has reached a position where processing of each processing unit is started. As each sensor, a reflective photosensor or the like is used. When it is detected that the check 100 has reached an appropriate position, the CPU 20 starts processing by each processing unit.

(Flow of payment by check payment system)
With reference to FIG. 4, the flow of settlement by the check settlement system 1 will be described. When the customer desires electronic payment by check 100 for shopping or meal payment, the store clerk inputs the payment amount into the host computer 3 and then inputs an instruction for electronic payment. Also, enter the presence or absence of a book. When the store clerk's input is completed, the host computer 3 transmits a reading command for reading the settlement information from the check 100 to the composite processing apparatus 2 (ST1).

  When the store clerk inserts the check 100 into the insertion slot 11 of the composite processing apparatus 2 with the surface of the check 100 being swung up, the composite processing apparatus 2 that has received the reading command (ST2) removes the check 100 according to the reading command. It is conveyed to the magnetic ink character reading unit 50, and payment information such as an account number is read from the MICR recording area 101 (ST3). CPU 20 transmits the read settlement information to host computer 3 (ST4).

When the host computer 3 receives the settlement information (ST5), the host computer 3 inquires the settlement institution server 4 about the validity of the check 100 based on the settlement information (ST6). When the validity of the check 100 is confirmed (ST7), the host computer 3 performs a settlement process (ST8) and transmits a print command for printing a necessary endorsement on the back side of the check 100 to the composite processing apparatus 2. To do. In addition, if there is an input indicating that there is no book on the check surface in advance, a print command for printing the necessary book is transmitted based on the payment amount entered in the host computer 3. Further, in order to save the surface image of the check 100 as evidence of electronic payment by the check 100, a scan start command for scanning and discharging the check 100 is transmitted (ST9). If the validity of the check 100 is not confirmed, the host computer 3 transmits a check discharge command to the composite processing apparatus 2, and the check 100 is discharged from the composite processing apparatus 2 (not shown).

  When the print command and the scan start command are received (ST10), the CPU 20 of the combined processing apparatus 2 conveys the check 100 to the endorsement printing unit 60 and prints the necessary endorsement in accordance with these commands (ST11). If a book print command has been received, the check 100 is conveyed to the book print unit 65 to print a necessary book (ST11).

  When printing is completed, the CPU 20 conveys the check 100 to the scanner unit 40 in accordance with a scan start command, and starts scan processing (ST12). In the scanner unit 40, first, a predetermined area of the check 100 is pre-scanned with 256 gradations (ST100), and 256-gradation pre-scan image data (first image data) is obtained. Then, an attempt is made to calculate a threshold value for binarizing the image data obtained by scanning the entire surface of the check 100 from the pre-scan image data. In this example, the CPU 20 calculates the luminance distribution of each pixel from the prescan image data, and determines an appropriate threshold value from the characteristics of the luminance distribution (ST101). A known algorithm can be used to determine the threshold value.

  Here, the threshold value may not be determined from the luminance distribution. For example, when the feature cannot be determined from the luminance distribution, for example, when the background pattern of the check is dark, the CPU 20 cannot determine an appropriate threshold value. In this case, the CPU 20 generates a pre-scan error (ST102). The processing when the CPU 20 generates a pre-scan error will be described later.

  If an appropriate threshold is determined and no pre-scan error occurs, the signature, payee, date, amount on the check surface will be displayed even if the image data obtained by performing the main scan of the check 100 is binarized. Therefore, it is determined that there is no loss of information that is proof of settlement such as an account number, and that the information can be discriminated even from the two-tone image data. Therefore, the scanner unit 40 performs a main scan that scans the entire surface of the check 100 (ST103). Image data of 256 gradations (second image data) is obtained by the main scan.

  Next, the CPU 20 binarizes the obtained 256-gradation image data based on the threshold value determined in ST101, and generates 2-gradation image data (first 2-gradation image data). (ST104). When the two gradation image data is generated, the CPU 20 transmits the generated two gradation image data to the host computer 3 (ST105). In this embodiment, together with the generated two-tone image data, the two-tone image data is provided with attribute information indicating that the pre-scan error does not occur and is processed “normally” in the host computer 3. Send. The check 100 for which the scanning process (ST12) is completed is conveyed as it is and discharged from the discharge port 13 (ST13).

  The host computer 3 that has received the two-tone image data and the attribute information (ST14) records them together with the settlement data such as the account number and amount of the check 100 in the storage device 7 (ST15). Then, an accounting statement and consent issuance command are transmitted to the composite processing apparatus 2 (ST16).

The CPU 20 of the composite processing apparatus 2 that has received the issue command (ST17)
The roll paper printing unit 70 is allowed to issue a bill of accounting and two consent forms (ST18). At the store, the account statement and two consent forms are delivered to the customer together with the discharged check 100. After receiving the shopper's signature on the positive consent form, collect it and store it at the store. This completes the electronic payment procedure using the check 100.

(When a pre-scan error occurs)
In the scan process (ST12), when an appropriate threshold value is not determined from the information obtained from the prescan and a prescan error occurs (ST102), processes performed after that will be described below.

  The fact that the CPU 20 cannot determine an appropriate threshold value from the image data obtained by pre-scanning means that, when the image data obtained by the main scanning is binarized, evidence of the settlement written on the check surface This means that there is a high possibility that a part of the information will be lost. Therefore, in the conventional composite processing apparatus, the generated prescan error is transmitted to the host computer, and the host computer (application) performs error processing. In addition, after the error processing, the host computer waits for a command for a main scan with new settings to be sent.

  However, even if a pre-scan error occurs, the composite processing apparatus 2 according to the present embodiment moves to the next processing step without performing error processing by the host computer 3. In addition, a plurality of processing operations are defined in advance as processing operations of processing steps to be shifted after the occurrence of a pre-scan error, and it is possible to set which processing operation is performed.

  Which processing operation is to be performed is determined by transmitting a setting command for setting the processing operation of the image processing device 2 in advance in the step (ST9) in which the host computer 3 transmits a scan start command to the composite processing device 2. Can be set. Further, it can be set in advance by a setting command transmitted from the host computer 3 to the image processing apparatus 2 when the check settlement system 1 is initialized. In this embodiment, the following three are defined as processing operations.

  In the first processing operation, after the pre-scan error occurs, the entire check is scanned in 256 gradations (ST111), and the obtained 256 gradation image data (second image data) is not subjected to image processing. Is transmitted to the host computer 3 (ST112). Further, when transmitting image data to the host computer 3, the attribute information indicating that “the pre-scan error has occurred and the setting has been changed and scanned” is added and transmitted.

  In the first processing operation, the binarization process is not performed on the image data of 256 gradations obtained in the main scan (ST111). Accordingly, the data capacity of the image data is larger than that of the two gradation image data. However, since it is possible to avoid the loss of information that is evidence of settlement that may be lost if binarization processing is performed, the image data transmitted to the host computer 3 is used as evidence of the settlement by the check 100. Can be adopted.

  In the second processing operation, after the pre-scan error occurs, the entire check is subjected to main scanning with 256 gradations (ST121), and the obtained 256 gradation image data (second image data) is sharpened (ST122). ) And binarization processing (ST123) are performed in this order to generate two-tone image data (third image data: second two-tone image data). The generated two-tone image data is transmitted to the host computer 3 together with attribute information indicating that “the pre-scan error has occurred and the setting has been changed and scanned” (ST124).

Here, the sharpening process is an image process in which an edge region such as an outline of a character or a pattern written on the surface of a check is highlighted. An edge region is a region where a difference in pixel value (luminance) between a target pixel and surrounding pixels is equal to or greater than a predetermined threshold. For the sharpening process, for example, a method disclosed in Japanese Patent Application Laid-Open No. 2004-54510 can be employed.

  If the image data of 256 gradations obtained by the main scan is sharpened, the background of the dark tone is removed as a whole, and sharp image data in which the contours of characters and the like written on the surface of the check 100 are emphasized is obtained. It is done. Therefore, if binarization processing is performed on this sharp image data, information that is evidence of settlement that may be lost when image data in a normal state is binarized is lost. Bi-level image data can be generated without being binarized. In addition, since two-gradation image data is finally obtained, the data capacity is small, and it is suitable for transfer and storage of image data. The threshold value for the binarization process is a setting threshold value that is set in advance in the composite processing apparatus 2, but the value of the setting threshold value is set to a desired value depending on the value of an argument of the command for the setting command or the scan start command. You may make it changeable.

  The third processing operation is performed by performing the main scan and binarization processing without changing the reference setting value preset in the memory 21 of the composite processing apparatus 2 after the pre-scan error occurs. The gradation image data is transmitted to the host computer 3. Referring to FIG. 4, the main scan is performed with 256 gradations, which is a reference gradation set in advance in the composite processing apparatus 2 (ST131), and the obtained 256 gradation image data (second image). The image data) is binarized based on a preset reference threshold value (ST132), and two-tone image data (third image data: third two-tone image data) Is generated. The generated two-tone image data is transmitted to the host computer 3 together with attribute information indicating that “a pre-scan error has occurred, but scanning has been performed without changing the setting” (ST133).

  According to the third processing operation, there is a possibility that information as evidence of settlement cannot be determined from the generated two-tone image data. However, the image data obtained by scanning the surface of the check 100 is necessary only when a trouble occurs due to electronic payment, and from such an empirical rule that it is not necessary in many cases, such processing is necessary. Can be selected. In response to a scan start command from the host computer 3, the composite processing apparatus 2 can transmit two-gradation image data with a small data capacity and terminate the transaction.

  Note that the check 100 for which the scanning process (ST12) has been completed is discharged from the discharge port 13 (ST13). Further, the check settlement process after ST14 in which the host computer 3 receives the image data and attribute information transmitted by the multi-processing apparatus 2 is the same as the process when no pre-scan error occurs.

  As described above, according to the present embodiment, even when a prescan error occurs, the host computer 3 does not process the generated error, and the image processing apparatus 2 performs the next processing step (ST111-112, ST121-124, ST131- 133), the second image data or the third image data is generated and transmitted to the host computer 3. Since error processing and transaction processing accompanying the occurrence of a prescan error are eliminated, error handling of an application installed in the host computer 3 can be simplified.

  In the composite processing apparatus 2, a plurality of processing operations are defined in advance as processing steps to be shifted when a pre-scan error occurs, and can be set in the step (ST9) in which the host computer 3 transmits a scan start command. It is like that. In addition, it can be set by a setting command transmitted from the host computer 3 when the check settlement system 1 is initialized. Therefore, even if a prescan error occurs, the host computer 3 can always acquire image data that has undergone desired image processing. Therefore, it is easy to construct an application installed in the host computer 3.

1 is an external view of a check settlement system including a composite processing apparatus to which the present invention is applied. It is a block block diagram of a check settlement system. It is a schematic sectional drawing which shows the structure around the conveyance path of the check of a composite processing apparatus. It is a flowchart which shows the flow of a process of a check payment system.

Explanation of symbols

1. Check payment system 2. Compound processing device 3. Register device (host computer) 4. Settlement server 5. Panel unit 6. Accounting display unit 7. Storage device 8. Credit card reader unit 20, 30 CPU, 21 memory, 40 scanner unit, 50 magnetic ink character reading unit, 60 endorsement printing unit, 65 cover printing unit, 70 roll paper printing unit, 80 check transport unit, 90・ Check position detection unit, 100 ・ Check, 101 ・ MICR recording area

Claims (8)

A receiving step of receiving a scan start command from the host computer;
When receiving the scan start command, a pre-scan process of scanning at least a part of the surface of the medium to be read and acquiring the first image data with a gradation higher than two gradations;
A threshold value determining step for determining a threshold value for binarizing the first image data based on the obtained first image data;
A main scanning step in which at least a part of the surface of the medium is scanned to acquire second image data with a gradation higher than two gradations;
A two-tone image data generating step for generating first two-tone image data by binarizing the second image data based on the threshold value when the threshold value is determined in the threshold value determining step. When,
An image data transmission step of transmitting the first two-tone image data to the host computer;
When the threshold value cannot be determined in the threshold value determination step, the threshold value cannot be determined for the second image data or the third image data obtained by performing predetermined image processing on the second image data. An image acquisition method for an image processing apparatus, comprising: a processing step of adding error information indicating that the error has occurred and transmitting the error information to the host computer. In claim 1,
The third image data is a second image obtained by sharpening the second image data to generate sharp image data, and binarizing the sharp image data based on a preset threshold value. An image processing method for an image processing apparatus, characterized in that the image data is two-tone image data. In claim 1,
The third image data is third two-tone image data obtained by binarizing the second image data based on a preset threshold value. Image acquisition method. In claim 1,
An image acquisition method for an image processing apparatus, comprising: a setting step for setting which of the following (1) to (3) a processing operation in the processing step is performed based on a setting command from the host computer .
(1) Processing operation for adding the error information to the second image data and transmitting it to the host computer. (2) As the third image data, sharpening processing is performed on the second image data to generate sharp image data. Then, the second two-tone image data obtained by binarizing the sharp image data based on a preset threshold value is adopted, and the error information is added to the second gradation image data to the host computer. Processing operation to be transmitted (3) As the third image data, third two-tone image data obtained by binarizing the second image data based on a preset threshold value is adopted. , Processing operation to which the error information is added and transmitted to the host computer In claim 4,
An image acquisition method for an image processing apparatus, wherein the setting command is received in the reception step. In any one of claims 1 to 5,
The image acquisition method for an image processing apparatus, wherein the first image data and the second image data are image data of 256 gradations. In any one of claims 1 to 6,
An image acquisition method for an image processing apparatus, wherein the medium to be read is a check. By the image acquisition method according to any one of claims 1 to 7,
An image processing apparatus for performing a reading operation on a surface of a medium to be read.

Images