JP2013175961A - Image reading device and image reading method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To more accurately and efficiently execute read processing of a manuscript and end portion detection processing of the manuscript.SOLUTION: A scanner unit 30 performs processing for transporting a manuscript S via a first path 11 and detecting a manuscript end portion from read image data by an end portion detection section 69. On the other hand, the scanner unit 30 performs processing for transporting the manuscript S via a second path 12 and storing the read image data as read image data 24a in a RAM 24. When detecting the manuscript end portion, the scanner unit 30 performs processing for not outputting data to the second path 12 and outputting the data to the first path 11. Thus, for example, when the read image data 24a is stored in the RAM 24, the scanner unit 30 prevents the read image data 24a from being overwritten by the image data for detecting the manuscript end portion and allows end portion detection of a subsequent manuscript S to be executed without being on standby until processing of the read image data 24a is completed.

Description

  The present invention relates to an image reading apparatus and an image reading method.

  Conventionally, an image reading apparatus has a configuration in which a light amount changing plate is inserted into and removed from a reading optical path in conjunction with a document detecting plate provided in a document conveying path, and the document detecting plate operates as the document is conveyed. Then, by canceling a change in the amount of light of a part of the read signal, an apparatus has been proposed in which the original detection unit is also used as the original reading unit without providing a dedicated original detection unit (see, for example, Patent Document 1). ). In this apparatus, the detection of the document is superimposed on the inside of the read signal, so that it can be realized with high reliability with a simple configuration without providing a dedicated document detection means.

Japanese Patent Laid-Open No. 7-264360

  By the way, in the apparatus of Patent Document 1 described above, a document is detected as a configuration in which a light amount change plate is inserted and removed, but such a configuration may be desired to be omitted. Further, there may be a case where the light amount changing plate cannot be provided. For example, how to detect a document when such a configuration is omitted has not been studied. In any case, in the image reading apparatus such as the apparatus of Patent Document 1 described above, it has been desired to more reliably and efficiently execute the document reading process and the document edge detection process.

  The present invention has been made in view of such a problem, and provides an image reading apparatus and an image reading method capable of more reliably and efficiently executing document reading processing and document edge detection processing. The main purpose.

  The present invention adopts the following means in order to achieve the main object described above.

The image reading apparatus of the present invention includes:
An image reading device that reads an image of a document conveyed by an automatic document conveyance device,
A reading unit for reading the conveyed document;
A first path which is a processing path for detecting a document edge from image data read by the reading unit;
A second path which is a processing path for storing the image data read by the reading unit in the storage unit as read image data;
A control unit that controls to output data to the first path instead of outputting data to the second path when detecting the document edge;
It is equipped with.

  In this image reading apparatus, an end portion of the original is detected from image data read by conveying the original through the first pass, and an image read by conveying the original through the second pass. When the process of storing the data as read image data is performed and the edge of the document is detected, the process of outputting the data to the first pass is performed without outputting the data to the second pass. For example, when the read image data is stored in the storage unit and the image data for detecting the document edge is output to the storage unit, the read image data may be affected. Considering this influence, it may be possible to wait for the detection of the document edge until the processing of the read image data is completed, but it is possible that the efficiency of the read processing is reduced. Here, when detecting the document edge, the data is not output to the second pass, but the data is output to the first pass, thereby preventing the influence on the read image data and the document edge. This detection process can be executed. Therefore, the document reading process and the document edge detection process can be more reliably and efficiently executed.

  In the image reading apparatus of the present invention, the control unit controls to output data to the first path and the second path when storing the read image data in the storage unit. It is good. In this way, for example, the edge detection process for detecting the edge of the document can be executed in parallel while executing the image reading process for generating the document reading data from the document. The part detection process can be executed more reliably and efficiently. The control unit may output data to the first path and the second path when detecting the trailing edge of the document.

  In the image reading apparatus according to the aspect of the invention, the control unit outputs data to the first path without outputting data to the second path when the reading unit finishes the reading process of one original. It is good also as what controls. In this way, the read image data can be further protected, and the document reading process and the document edge detection process can be more reliably and efficiently performed. Alternatively, the control unit may not output data to the second path when the read image data is stored in the storage unit. In this way, the read image data can be further protected, and the document reading process and the document edge detection process can be more reliably and efficiently performed.

  In the image reading apparatus according to the present invention, the automatic document feeder may not include the document detection sensor. In this way, document detection can be executed with a simpler configuration.

  An image reading apparatus of the present invention acquires image data read by the reading unit through the first path, and detects an end portion of a document based on the image data, and the reading unit The read image data is acquired via the second pass, and the storage unit that stores the image data as the read image data, and the first pass and the second pass are switched by the control of the control unit. And a path switching unit.

  In the image reading apparatus according to the aspect of the invention including the edge detection unit and the storage unit, the edge detection unit may detect the leading edge of the document based on the image data. In this way, the document reading process and the document leading edge detection process can be executed more reliably and efficiently. Alternatively, the edge detection unit may detect the trailing edge of the document based on the image data.

  In the image reading apparatus according to the aspect of the invention including the edge detection unit and the storage unit, the edge detection unit temporarily stores image data for detecting the edge of the document. It is good also as what is equipped with. In this way, the image data can be held in the storage unit, so that the edge detection of the document can be more reliably performed.

The image reading method of the present invention includes:
An image reading method using an image reading apparatus provided with a reading unit for reading an original conveyed by an automatic original conveying apparatus,
When detecting the edge of the document, the image data is output to a first path which is a processing path for detecting the edge of the document from the image data read by the reading unit, and is read by the reading unit. The second path which is a processing path for storing the image data as read image data in the storage unit includes a process of not outputting the image data.

  In this image reading method, similarly to the above-described image reading apparatus, when detecting the document edge, data is not output to the second pass, but data is output to the first pass, thereby reading the read image. Since the influence on the data is prevented and the document edge detection process can be executed, the document reading process and the document edge detection can be more reliably and efficiently executed. In this image reading method, various aspects of the above-described image reading apparatus may be adopted, and steps for realizing each function of the above-described image reading apparatus may be added.

FIG. 2 is a configuration diagram illustrating an outline of a configuration of a multifunction printer 20. 6 is a flowchart illustrating an example of a document edge detection reading process routine.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram showing an outline of a configuration of a multifunction printer 20 according to an embodiment of the present invention. The multi-function printer 20 according to the present embodiment includes a controller 21 that controls the entire apparatus, a network interface (I / F) 26 that communicates with an external device, a display unit, and an operation unit. An operation panel 28 that can perform image reading, a scanner unit 30 that optically reads a document to generate image data, and a printer unit 70 that prints an image on a print medium.

  The controller 21 is configured as a microprocessor centered on the CPU 22, and includes a flash memory 23 that stores various processing programs, various data, various tables, and the like, and a RAM 24 that temporarily stores scan data and print data. . The controller 21 inputs various operation signals and various detection signals from the scanner unit 30 and the printer unit 70 and inputs operation signals generated in response to a touch operation on the operation panel 28. Further, the controller 21 outputs a command to the scanner unit 30 to read a document as image data based on a scan command from the operation panel 28, and outputs a command to the printer unit 70 to execute printing of image data. To do.

  The operation panel 28 includes a display unit disposed in the center and an operation unit configured to include the display unit. The display unit is configured as a touch panel type liquid crystal display, and a mode button for selecting a mode, a selection / setting button for selecting a menu or an item by touching according to guidance displayed on the display, scanning or copying, A start button for starting printing is displayed and a touch operation is accepted.

  The scanner unit 30 includes a scanner ASIC 31 that controls the scanner engine 32 and a scanner engine 32 having a contact image sensor module (CISM) 34 and the like. The scanner engine 32 uses a flatbed portion 40 that optically reads a document placed on the glass table 41 and a document set by the document guide 39 and set in the ADF insertion port 37a as an ADF reading region. An ADF unit 44 that automatically conveys to the contact glass 42, and a CIS module (CISM) 34 that reciprocates by driving the belt 52 spanned between the carriage motor 51a and the driven roller 51b by the carriage motor 51a.

  The CISM 34 is a module for reading a document placed on the glass table 41 or a document S conveyed to the contact glass 42. The light source unit 35 for irradiating light and the light reflected from the document by a light receiving element are charged. And a CIS 36 for reading a document by storing as. The light source unit 35 has three color light sources, a red LED that turns on red light, a green LED that turns on green light, and a blue LED that turns on blue light. 42 is irradiated. The CIS 36 is configured such that a plurality of light receiving elements (for example, CMOS image sensors) for one line are arranged in the main scanning direction, and color is obtained by reading reflected light one by one while sequentially switching on / off the LEDs of each color. Generate image data. In addition, the CISM 34 has a function of outputting the average value of the entire CIS 36 in addition to outputting the charge of each light receiving element individually. The CISM 34 is configured to execute an edge detection process for detecting an edge of the document S and an image reading process that is a main scan of the document S. The CISM 34 includes a detection sensor for the document S, an image reading sensor for the document S, and the like. Doubles as

  The ADF unit 44 is configured as an automatic document feeder that transports the document S along the transport path 45 to the contact glass 42 readable by the CISM 34. The ADF unit 44 automatically drives a plurality of transport rollers 46 arranged in the transport path 45 by the transport motor 53 to take the originals set in the ADF insertion port 37a one by one on the transport path 45. Transport. The ADF unit 44 faces the contact glass 42, and a support member 48 that supports the conveyed document S is disposed at a position where the conveyed document S passes between the ADF unit 44 and the CISM 34. The support member 48 may be formed in a color having little influence on document reading, for example, an achromatic color, and is formed in gray here. In the ADF unit 44, for example, a non-contact type (for example, optical) or contact type paper detection sensor is omitted, and a process of detecting an end portion of the conveyed document S by reading the document S by the CISM 34. Is set to run.

  The scanner ASIC 31 is an integrated circuit that controls the scanner engine 32. Upon receiving a scan command from the controller 21, the scanner ASIC 31 reads the document S on the glass table 41 or the document S conveyed by the ADF unit 44 as image data. The engine 32 is controlled. The scanner ASIC 31 includes a reading processing unit 61 including a control unit 62 that controls each device and a shading correction processing unit 63 that performs shading correction on the read data. The scanner ASIC 31 receives a control signal from the reading processing unit 61, a motor driving unit 64 that drives the carriage motor 51a and the conveyance motor 53, an LED driving unit 65 that individually turns on and off each color LED, and a CIS 36. An A / D conversion unit 66 that inputs the generated analog signal through an amplifier (not shown) and converts it into a digital signal is provided. The shading correction process uses the white reference data W and the black reference data K to remove density unevenness that occurs for each pixel due to variations in light emission of the light source unit 35 and variations in sensitivity characteristics of each light receiving element ( (Shading correction). A white reference plate 43 for white shading correction is provided at an end of the glass table 41 in the sub-scanning direction, that is, at a position different from the background member 48. The black reference data K is an output voltage obtained by the light receiving element when all the light sources are turned off and the white reference plate 43 is scanned, and the white reference data W is scanned with the LEDs of each color turned on. This is sometimes the output voltage obtained by the light receiving element.

  The scanner ASIC 31 also connects the first path 11 that is a processing path for detecting a document edge from image data that is connected to the reading processing unit 61 and read by the CISM 34, and image data that is connected to the reading processing unit 61 and read by the CISM 34. A second path 12, which is a processing path for storing the read image data 24a in the RAM 24, and a path for outputting data to the first path 11 without outputting data to the second path 12 when detecting the edge of the document S. A switching unit 67. In addition, the scanner ASIC 31 acquires the image data read by the CISM 34 via the first path 11 and temporarily stores the image data in the monitor unit 68 as an end detection storage unit, and the image data stored in the monitor unit 68. And an edge detection unit 69 for detecting the edge of the document S based on the document. The path switching unit 67 outputs the image read by the CISM 34 only to the first pass 11 side according to the processing content of the scanner unit 30 according to the command from the control unit 62 of the reading processing unit 61, or the first pass 11 And a function of switching whether to output to the second path 12. The monitor unit 68 is constituted by a register and has a smaller storage capacity than the RAM 24. The edge detection unit 69 has a function of detecting the edge of the document S based on whether the image data stored in the monitor unit 68 is the support member 48 or the document S. The edge detection unit 69 outputs a signal of the detection result of the edge of the document S to the reading processing unit 61.

  The printer unit 70 includes a printer ASIC 71 and a printer engine 72. The printer ASIC 71 is an integrated circuit that controls the printer engine 72. Upon receiving a print command from the controller 21, the printer ASIC 71 controls the printer engine 72 to print an image on a print medium based on an image file that is a target of the print command. The printer engine 72 is configured as a well-known inkjet color printer mechanism that performs printing by discharging ink from a print head to a print medium.

  Next, the operation of the multi-function printer 20 of the present embodiment configured as described above, particularly the process of reading the document S conveyed by the ADF unit 44 in the scanner unit 30 will be described. FIG. 2 is a flowchart showing an example of a document edge detection reading process routine executed by the scanner ASIC 31. This document edge detection and reading processing routine is executed after a scan command for reading the document S conveyed by the ADF unit 44 by the CISM 34 is input from the operation panel 28 or the like. In this document edge detection and reading process, the reading processing unit 61 has functions such as a motor drive unit 64, an LED drive unit 65, an A / D conversion unit 66, a path switching unit 67, a monitor unit 68, and an end detection unit 69. It shall be used and executed.

  When this routine is executed, the reading processing unit 61 switches the path switching unit 67 so that the read image data is not output to the RAM 24 side but to the end detection unit 69 side (step S100). That is, image data is output only to the first pass 11 side. Thus, when the leading edge of the document is detected, the reading image data 24a stored in the RAM 24 is prevented from being affected when the image at the leading edge of the document is read. Next, the document S is transported by the ADF unit 44 and the edge reading process in the ADF reading area is executed (step S110). Hereinafter, it is assumed that the document S conveyance process and the edge reading process are continuously performed. In the edge reading process in the ADF reading area, the reading processing unit 61 generates RGB data based on the signal input from the A / D conversion unit 66, and executes shading correction processing or the like to generate image data. Execute. At this time, when the document S has not reached the ADF reading area, the image data of the support member 48 is obtained, and when the document S has reached the ADF reading area, the image data of the document S is obtained.

  Subsequently, the reading processing unit 61 performs a leading edge detection process (step S120), and determines whether or not the leading edge of the document S is detected during conveyance of a predetermined distance (step S130). In the leading end detection process, it is determined whether the image data input from the reading processing unit 61 is within a predetermined color gamut range based on the color of the support member 48. At this time, the end detection unit 69 may use image data based on an average value (RGB value) of the entire CIS 36 (for one line) output from the CISM 34 for determination. When the color gamut is out of the color gamut, the leading edge of the conveyed document S is detected. If the leading edge of the document S is not detected during conveyance of the predetermined distance, a message is displayed on the operation panel 28 (step S220), and this routine is terminated as it is. Here, for example, a message such as “The document could not be detected” may be displayed. The predetermined distance is empirically set to a distance based on the transport distance from the ADF insertion port 37a to the ADF reading area, for example, a distance obtained by adding a predetermined margin to the transport distance from the ADF insertion port 37a to the ADF reading area. May be. Note that the case where the leading edge of the document S is not detected during conveyance of a predetermined distance includes the case where the next document S does not exist and the case where the document S is jammed in the conveyance path 45 during conveyance.

  On the other hand, when the leading edge of the document S is detected in step S130, the reading processing unit 61 outputs the read image data to the RAM 24 side and the edge detection unit 69 side in order to execute the main scan of the document S. The path switching unit 67 is switched (step S140). That is, image data is output to both the first pass 11 and the second pass 12. In this way, the image reading process of the document S and the trailing edge detection process of the document S can be executed in parallel. The read image data 24a stored in the RAM 24 is processed approximately during the leading edge detection process in step S120 and is output to the subsequent stage (for example, the printer unit 70).

  Next, the reading processing unit 61 executes the trailing edge detection process of the document S while executing the image reading process of the document S (step S150), and determines whether the trailing edge of the document S is detected (step S150). Step S160). In the image reading process of the document S, a process of storing the read image data output from the reading processing unit 61 in the RAM 24 is executed. Further, in the trailing edge detection process, as in the leading edge detection process described above, the trailing edge of the conveyed document S is detected when the image data changes from outside the color gamut of the support member 48 to within the color gamut. When the trailing edge of the document S is detected, it is assumed that the image reading process is completed (step S170), and the processes after step S100 are executed. That is, image data is output only to the first pass 11 side, the automatic conveyance of the document S is executed, and the leading edge detection process is executed. As described above, when the image reading process for one document S is completed, the path switching unit 67 is switched so that the image data is not output to the second path 12 but the image data is output to the first path 11. Thus, by outputting the image data only to the first pass 11 side, the read image data 24a of the document of the previous page is overwritten with the image data generated by executing the leading edge detection process of the document of the next page. This prevents the influence on the read image data 24 a stored in the RAM 24.

  On the other hand, if the trailing edge of the document S has not been detected in step S160 and the image reading process has not ended (step S180), the processes in and after step S150 are executed. That is, the image reading process of the document S and the trailing edge detection process of the document S are continuously executed. On the other hand, when the trailing edge of the document S is not detected in step S160 and the image reading process is completed in step S180, the read image data is not output to the RAM 24 side but is output to the edge detecting unit 69 side. Switching is performed by the path switching unit 67 (step S190). That is, image data is output only to the first pass 11 side. As described above, when the image reading process for one document S is completed, the path switching unit 67 is switched so that the image data is not output to the second path 12 but the image data is output to the first path 11. In this way, image data is output only to the first pass 11 side, and the read image data 24a of the document S is prevented from being overwritten by image data generated by execution of the trailing edge detection process, and the read stored in the RAM 24 is prevented. The influence on the image data 24a is prevented. Note that the case where the image reading process is completed without detecting the trailing edge of the document S, for example, an image reading command for the document S is issued with a setting for scanning a part of the document S, and the image reading process for the document S is completed. For example, the remaining margin of the original S is being conveyed.

  Subsequently, the reading processing unit 61 performs a trailing edge detection process while conveying the document S (step S200), and determines whether or not the trailing edge of the document S is detected during conveyance of a predetermined distance (step S200). S210). The predetermined distance here is, for example, a distance based on the size of the document S specified in the scan setting, for example, a distance obtained by adding a predetermined margin to the size of the document S specified in the scan setting. It may be set. When the trailing edge of the document S is detected during the conveyance of the predetermined distance, the processes after step S100 are executed. That is, image data is output only to the first pass 11 side, the automatic conveyance of the document S is executed, and the leading edge detection process is executed. As described above, by outputting the image data only to the first pass 11 side, the read image data 24a of the document on the previous page is overwritten with the image data generated by executing the leading edge detection process of the document on the next page. This prevents the influence on the read image data 24 a stored in the RAM 24.

  On the other hand, when the trailing edge of the document S is not detected during conveyance of the predetermined distance in step S210, a message is displayed on the operation panel 28 (step S220), and this routine is finished as it is. Here, for example, a message such as “Could not detect the trailing edge of the document” may be displayed.

  Here, the correspondence between the components of the present embodiment and the components of the present invention will be clarified. The ADF unit 44 of the present embodiment corresponds to the automatic document feeder of the present invention, the CIS module 34 corresponds to the reading unit, the first pass 11 corresponds to the first pass, and the second pass 12 corresponds to the second pass. The path switching unit 67 corresponds to the path switching unit, the RAM 24 corresponds to the storage unit, the end detection unit 69 corresponds to the end detection unit, and the monitor unit 68 corresponds to the end detection storage unit. Equivalent to. In this embodiment, an example of the image reading method of the present invention is also clarified by describing the operation of the scanner unit 30.

  According to the multifunction printer 20 of the present embodiment described in detail above, the end detection unit 69 detects the end of the document from the image data read by conveying the document S through the first pass 11, while the first The image data read by conveying and reading the document through the two-pass 12 is stored in the RAM 24 as the read image data 24a, and the data is not output to the second path 12 when the document edge is detected. The process of outputting data to the first path 11 is performed. For example, when the scanned image data 24a is stored in the RAM 24 and the image data for detecting the edge of the document is output to the RAM 24, the scanned image data 24a is overwritten. Can give. In consideration of this influence, it may be possible to wait for the detection of the document edge until the processing of the read image data 24a is completed, but it is possible that the efficiency of the image reading process is reduced. Here, when the document edge is detected, the data is not output to the second pass 12 but the data is output to the first pass 11, thereby preventing the influence on the read image data 24 a and the document edge. Part detection processing can be executed. Therefore, the image reading process of the document S and the edge detection process of the document S can be executed more reliably and efficiently.

  Further, when the read image data 24a is stored in the RAM 24 or when the trailing edge of the document S is detected, the image data is output to the first path 11 and the second path 12, for example, the document S to the document While performing the image reading process for generating the read data 24a, the edge detection process for detecting the document edge can be performed in parallel, and the reading process of the document S and the edge detection of the document S can be performed more reliably. And can be executed efficiently. Further, when the CISM 34 completes the image reading process for one document S, the data is not output to the second pass 12 but is switched to output the image data to the first pass 11, so that the read image data 24a is further protected. Thus, the image reading process of the document S and the edge detection process of the document can be more reliably and efficiently performed. Furthermore, since the ADF unit 44 does not include a detection sensor for the document S, document detection can be performed with a simpler configuration. Then, detection of the leading edge and trailing edge of the document S can be executed based on the image data. In addition, since the monitor unit 68 that temporarily stores the image data for detecting the end portion of the document S is provided, the end portion of the document S is more reliably detected by holding the image data in the monitor unit 68. Can be executed.

  It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that the present invention can be implemented in various modes as long as it belongs to the technical scope of the present invention.

  For example, in the above-described embodiment, when the read image data 24 a is stored in the RAM 24, the image data is output to the first pass 11 and the second pass 12. When the read image data 24 a is stored in the RAM 24, the image data may be output only to the second path 12. For example, when the reading area of the document S on which the image reading process is executed is designated, image data may be output only to the second pass 12 for this reading area. Further, after exceeding the reading area, the image data may be output only to the first pass 11. Even in this case, the image reading process of the document S and the edge detection process of the document S can be more reliably and efficiently performed. Note that the processing itself for detecting the trailing edge of the document S may be omitted.

  In the above-described embodiment, when the image reading process for one document S is completed, the image data is not output to the second pass 12 but switched to output the image data to the first pass 11. For example, when the read image data 24 a is stored in the RAM 24, the image data may not be output to the second path 12. Even in this case, the read image data 24a can be further protected, and the image reading process of the document S and the edge detection process of the document S can be more reliably and efficiently performed.

  In the embodiment described above, the leading edge and the trailing edge of the conveyed document S are detected. However, the present invention is not particularly limited to this, and the side edge of the conveyed document S may be detected. .

  In the above-described embodiment, the multi-function printer 20 has been described. However, the multi-function printer 20 is not particularly limited as long as the end of the conveyed document S is detected. For example, a scanner device that does not include the printer unit 70 may be used. A FAX apparatus having a FAX function may be used. The printer unit 70 is an inkjet color printer mechanism, but is not particularly limited to this, and may be an electrophotographic color printer, a dot impact color printer, or a monochrome printer of these. It is good.

  In the above-described embodiment, the multi-function printer 20 has been described. However, an image reading method or a program for executing this method may be used.

11 First pass, 12 Second pass, 20 Multi-function printer, 21 Controller, 22 CPU, 23 Flash memory, 24 RAM, 24a Scanned image data, 26 Network interface (I / F), 28 Operation panel, 30 Scanner unit, 31 Scanner ASIC, 32 Scanner engine, 34 CIS module, 35 Light source unit, 36 CIS, 37 Document tray, 37a ADF insertion slot, 38 ADF discharge tray, 39 Document guide, 40 Flatbed section, 41 Glass stand, 42 Contact glass , 43 White reference plate, 44 ADF unit, 45 transport path, 46 transport roller, 48 support member, 51a carriage motor, 51b driven roller, 52 belt, 53 transport motor 61 reading processing unit 62 control unit 63 shading correction processing unit 64 motor driving unit 65 LED driving unit 66 A / D conversion unit 67 path switching unit 68 monitor unit 69 end detection unit 70 printer Unit, 71 Printer ASIC, 72 Printer engine, S Original.

Claims (8)

An image reading device that reads an image of a document conveyed by an automatic document conveyance device,
A reading unit for reading the conveyed document;
A first path which is a processing path for detecting a document edge from image data read by the reading unit;
A second path which is a processing path for storing the image data read by the reading unit in the storage unit as read image data;
A control unit that controls to output data to the first path instead of outputting data to the second path when detecting the document edge;
An image reading apparatus comprising:   2. The image reading according to claim 1, wherein when the read image data is stored in the storage unit, the control unit controls the data to be output to the first pass and the second pass. apparatus.   The control unit controls to output data to the first path without outputting data to the second path when the reading unit finishes the reading process of one original. The image reading apparatus according to 1 or 2.   The image reading apparatus according to claim 1, wherein the automatic document feeder does not include a detection sensor for the original. The image reading apparatus according to any one of claims 1 to 4,
An edge detection unit that acquires image data read by the reading unit via the first path and detects a document edge based on the image data;
A storage unit that acquires the image data read by the reading unit via a second path and stores the image data as the read image data;
An image reading apparatus comprising: a path switching unit that switches between the first path and the second path under the control of the control unit.   The image reading apparatus according to claim 5, wherein the edge detection unit detects a leading edge of the document based on the image data.   The image reading apparatus according to claim 5, wherein the edge detection unit includes an edge detection storage unit that temporarily stores image data for detecting an edge of the document. An image reading method using an image reading apparatus provided with a reading unit for reading an original conveyed by an automatic original conveying apparatus,
When detecting the edge of the document, the image data is output to a first path which is a processing path for detecting the edge of the document from the image data read by the reading unit, and is read by the reading unit. Do not output the image data to the second path which is a processing path for storing the image data as read image data in the storage unit;
Image reading method.