JP2004032571A - IMAGE READING DEVICE, IMAGE READING DEVICE CONTROL METHOD, AND IMAGE READING DEVICE CONTROL PROGRAM - Google Patents

Abstract

A highly functional and complex image reading system capable of efficiently and accurately performing an image reading process with a simple and inexpensive configuration.
A document size of a document surface is detected from image information obtained by pre-scanning a document surface for image reading prior to image reading, and an image of the document surface is detected using the obtained document size information. When reading is controlled, a document size is detected by performing a line-by-line search process (FIGS. 6 to 10) and / or a pixel-by-pixel search process (FIGS. 11 to 15). In the case of performing the search processing in both the line unit and the pixel unit, the search processing in both the line unit and the pixel unit (S1701, S1702) is executed for each of the document size determination in the main scanning direction and the document size determination in the sub scanning direction The two results are combined (for example, the larger size is adopted: S1704 to S1705).
[Selection diagram] FIG.

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention detects a document size of a document surface from image information obtained by prescanning a document surface for image reading prior to image reading, and reads an image of the document surface using the obtained document size information. The present invention relates to an image reading device that performs image reading for controlling the image reading device, a method of controlling the image reading device, and a control program of the image reading device.
[0002]
[Prior art]
Conventionally, an image reading apparatus has been commercialized as a peripheral device (image scanner) for a single function computer, as well as a facsimile apparatus and a copying machine, and more recently, a plurality of functions such as image reading, copying, facsimile transmission, and the like. Widely used for MFPs (Multi Function Peripherals).
[0003]
In many image reading devices, reading scanning is performed by the relative movement between the reading head and the document, but if the reading method of the image reading device is classified according to the document conveying method, the document is placed on the document glass and read. There are a method of moving the head, and a method of moving the original without moving the reading head. In addition to manual feeding, a configuration in which an original is sent to a reading position (regardless of whether the original or the reading head is fed) by an ADF (automatic original feeding device) is used. ing.
[0004]
Further, it is not uncommon for current image reading apparatuses to be able to use not only a single reading method but also two or more reading methods. For example, an apparatus that can use both the ADF reading method and the flatbed reading method is available. Exists.
[0005]
In addition, at present, not only is the image of the read document simply recorded on the recording paper or transmitted by facsimile, various controls are performed during the process from reading the document to using the document image. Accordingly, it has become commonplace to implement a plurality of different processing functions on a document image.
[0006]
For example, there are the following types of copy functions even if only the copy (copy) is listed.
[0007]
(1) Normal copy that simply copies the original
(2) Repetitive copy (manual) in which an original is repeatedly copied onto recording paper by the number of repetitions specified by the operator
(3) Repeat copying to copy the original as much as possible on the recording paper (automatic)
(4) Mirror image copy in which the original is reversed and copied as if mirrored
(5) Full copy to copy the entire original in consideration of the printable area of the recording unit
(6) Automatic magnification copy that automatically determines the magnification and copies the entire recording paper size
As a control performed when reading a document, there is a control for detecting a document size when reading a document. In particular, in a copy mode as described in (3) and (6) above, the original size is detected and the subsequent processing (repetitive copy or automatic scaling copy) is controlled.
[0008]
[Problems to be solved by the invention]
As described above, the image reading apparatus may be required to have a configuration capable of using a plurality of reading methods such as an ADF reading method and a flatbed reading method. It is desirable that image processing can be performed by selecting a plurality of reading methods as simply and without error as possible.
[0009]
For example, in a method in which a plurality of reading methods are simply selected by a manual operation, the burden on the user is large, and there is a high possibility that the target image processing fails due to an operation error or the like. In particular, as the apparatus has more functions (for example, various copy functions exist as described above even for copy (copy)), an improper reading method is selected due to an operation error and image processing fails. The likelihood increases. For example, in the control of the reading process by a manual operation, a reading method (for example, an ADF method) in which pre-scanning is not possible, even though an image reading mode requiring pre-scanning for document size detection or the like is selected. There is a possibility of choosing.
[0010]
Therefore, in a configuration in which a plurality of reading modes can be selected and a plurality of reading modes can be used, it is desirable that the reading process can be surely performed without the user performing an extra operation. .
[0011]
An important control to be performed at the time of image reading is detection of a document size. The detection of the document size must be performed efficiently and accurately with a simple and inexpensive configuration. If the detection of the document size fails, sophisticated controls such as repetitive copying and automatic scaling copying using the result naturally fail.
[0012]
Conventionally, a configuration in which a dedicated original size sensor (such as an optical sensor or a sensor for detecting a position of a manually operated original guide) is known. However, a configuration in which a dedicated sensor is provided improves the productivity of the apparatus. Since it is difficult to reduce the size and cost, it has been proposed to detect an original size by analyzing an image obtained by performing a prescan with an optical sensor used for actual image reading.
[0013]
For example, in Japanese Patent Application Laid-Open No. H11-155060, a threshold value for judging the edge of an original is determined by analyzing the image density of the original from the image data obtained by reading the original, and the image data is analyzed again, and the threshold is determined at a constant rate. A position exceeding the threshold value is defined as a document edge (boundary position). Further, in Japanese Patent Application Laid-Open No. H11-225264, when it is not possible to detect the document edge (boundary position) by the above-described search method, the last point that can be detected is regarded as the document edge (boundary position).
[0014]
In the technique disclosed in Japanese Patent Application Laid-Open No. H11-155060, processing is time-consuming because image data analysis is performed in a multiplexed manner. In order to achieve high-speed processing, a device such as a CPU having a high processing capability is required for the apparatus. It is considered difficult to down. Further, in the technique disclosed in Japanese Patent Application Laid-Open No. H11-225264, estimating the document edge (boundary position) when the document size is erroneously detected may cause the document to be read only halfway, which is very inconvenient for the user. It is considered to be.
[0015]
Under the circumstances described above, there is a strong demand for a configuration that can efficiently and accurately detect a document size with a simple and inexpensive configuration.
[0016]
In view of the above problems, an object of the present invention is to make it possible to efficiently and accurately perform an image reading process with a simple and inexpensive configuration in a highly functional and complex image reading system.
[0017]
[Means for Solving the Problems]
In order to solve the above-described problems, according to the present invention, a document size of a document surface is detected from image information obtained by pre-scanning a document surface for image reading prior to image reading, and the obtained document is In an image reading apparatus that performs image reading for controlling image reading on the original surface using size information, a control method thereof, and a control program, the specific information in the image information obtained by the prescan is used as another reference data. A configuration is employed in which a search process for comparing with the information is performed, and the size of the document corresponding to the image information is obtained without searching the entire image information obtained by the prescan.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the configurations of the following embodiments (relative arrangement of components, dimensions, display screens, and the like) are not intended to limit the scope of the present invention only to them unless otherwise specified. Needless to say.
[0019]
Hereinafter, as one embodiment of the image reading apparatus, an MFP (Multi Function) having a scanning function, a printing function, and a copy function is described.
1 shows an embodiment of the present invention.
[0020]
<System configuration>
FIG. 1 shows a circuit configuration of an MFP employing the present invention.
[0021]
In FIG. 1, a CPU 101 is a system control unit of the MFP, and controls each block configuring the MFP.
[0022]
The ROM 102 stores a system control program of the MFP. The CPU 101 executes various operations related to the MFP based on a control program stored in the ROM 102. The control program of the CPU 101 is not limited to the program stored in the ROM 102, but may be a program stored in an external storage medium such as a flexible disk or a CD-ROM. (For example, an SRAM 104), and the CPU 101 may decode and execute the program.
[0023]
The printer 103 records read or input image data on recording paper, and is configured by an arbitrary image recording method (an electrophotographic method, an inkjet method, or the like).
[0024]
The SRAM 104 is mainly used for storing MFP registration data and the like, and the DRAM 105 is mainly used for storing image data and the like.
[0025]
The image processor 106 performs various types of image processing (image scaling, conversion to predetermined image format data, and the like) on image data input by the image sensor 107. The image sensor 107 is for reading an image on a document, and includes a contact-type reading sensor and the like.
[0026]
The operation panel 108 has a display 109 for displaying the status of the apparatus and the like, and is used for inputting operation instructions from an operator and registering various data. The display 109 is also used to allow the user to monitor the status of the device.
[0027]
The PC interface 110 is an interface that connects the MFP and a PC (personal computer) 111. The PC 111 is a host computer that can use the MFP as a peripheral device, change various setting data of the MFP, and request activation of various operations.
[0028]
FIG. 2 shows a configuration of a main part of an image reading unit of the MFP of FIG. In FIG. 2, the image reading unit is configured as a flatbed reading unit, and moves the image sensor 204 (corresponding to the image sensor 107 in FIG. 1) to read a document stacked on the document table 205. However, the image reading unit may be provided with an ADF as described later.
[0029]
In FIG. 2, a black-and-white reference plate 201 is a reference plate for generating shading data of the image sensor 204, and includes two color portions, a white portion and a black portion. By turning on or off an illumination light source (not shown) of the sensor 204, shading data of each color can be obtained.
[0030]
The document abutment position 202 functions as a reference for arranging the leading edge of the document as a reference for correctly loading the document on the document table 205.
[0031]
The pressure plate 203 is a lid for preventing external light from entering when reading a document. The inside is made of white sheet.
[0032]
An original table 205 is an original mounting table made of transparent glass. The image sensor 204 moves below the original table 205 by a driving unit (not shown) to scan the original. When the apparatus is in the standby state, the image sensor 204 is always waiting at the image sensor home position 206.
[0033]
FIG. 3 shows a configuration of the operation panel of the MFP of FIG. Hereinafter, each member in FIG. 3 will be described.
[0034]
A power key 301 is used to turn on / off the main power of the MFP.
[0035]
A recovery key 302 is used to release an error of the MFP.
[0036]
The memory use indicator LED 303 indicates the use state of the image memory. When the memory use indicator LED 303 is blinking, it means that the apparatus is using the memory.
[0037]
The error display LED 304 is for displaying an error. When the error display LED 304 is blinking, it means that the apparatus is in an error state.
[0038]
A mode switching key 305 is used to switch the standby state of the apparatus to a copy mode, a FAX mode, or a scanner mode.
[0039]
The color mode display LED 306 is for displaying a mode relating to color processing of an image. When the color mode display LED 306 is turned on, it means that the apparatus is in the color reading mode.
[0040]
The color / monochrome mode can be switched by a color / monochrome switching key 307. When the reading mode is color, the color mode display LED 306 is turned on, and when the reading mode is monochrome, the color mode display LED 306 is turned off.
[0041]
A stop key 308 is a key for stopping the operation of the apparatus, and a start key 309 is a key for starting the operation of the apparatus.
[0042]
Numeric keys 310 are used to input numerical values such as the number of copies and the telephone number of a facsimile communication partner.
[0043]
Switching of the image quality mode, for example, switching of the image quality of the copy image (or facsimile image) is performed by the copy image quality selection key 311.
[0044]
The copy density is adjusted by the copy density adjustment key 312.
[0045]
A recording paper size selection key 313 is used for setting a recording paper size set in the printer 103.
[0046]
The setting of the copy magnification of this apparatus is performed by the copy magnification setting key 314.
[0047]
The set key 315 is used to determine a setting item in various registration modes and the like.
[0048]
Various setting items can be displayed on the display 317 by the menu key 316.
[0049]
The display 317 corresponds to the display 109 shown in FIG. 1 and includes a liquid crystal display and the like.
[0050]
<Outline of operation>
The MFP shown in FIGS. 1 to 3 can perform operations such as image reading, original copy facsimile transmission and reception, and the like. The image reading unit detects the size of the document, particularly in the copy mode, and controls the image copy process using the detection result. The image size of the document is detected by performing the following processing on the image data of the document obtained by performing the prescan.
[0051]
First, the outline of the control executed by the CPU 101 will be described with reference to FIG. FIG. 4 shows an outline of control executed by the CPU 101 in the MFP, in particular, control relating to image reading control.
[0052]
In step S401 in FIG. 4, it is determined whether the mode is the copy mode by checking the state of the mode switching key 305. If the mode is the copy mode, the process waits for a copy instruction from the operator (step S402).
[0053]
If the FAX mode is set in step S407, the process waits for a facsimile instruction from the operator in step S408. After the operator sets copy settings such as magnification, density, image quality, recording paper size, and copy type, the start key 309 is pressed. (Step S409), facsimile transmission is performed (step S411).
[0054]
If the scan mode is not set in the FAX mode in step S407, the scan mode is set. Therefore, a scan instruction from the connected PC 111 is waited for (step S412). If there is a scan instruction from the PC 111, the scan instruction is issued in step S413. Perform a street scan.
[0055]
If there is no scan instruction from the PC 111, it is checked in step S414 whether the start key 309 has been pressed. If the start key 309 has been pressed, the scan mode is requested to the PC 111. If the desired scan mode has been acquired from the PC 111 (step S416), the image reading process according to the acquired scan mode is performed (step S417).
[0056]
In the FAX mode (steps S407 to S407) and the scan mode (steps S412 to S412), the document size may be detected by pre-scan, which will be described later. Document size detection is not performed.
[0057]
If the current state is the copy mode in step S401, after the operator has performed copy settings such as magnification, density, image quality, recording paper size, and copy type in step S402, the start key 309 is pressed ( It is checked whether or not the currently set copy type (copy mode) is a copy for which the original size is to be detected by the prescan (step S404).
[0058]
If the copy mode is a copy in which the original size is detected by the prescan, the original size is detected by the prescan in step S405, and the reading process is performed according to the detected original size in step S406. If document size detection by prescan is not performed, copy processing without document size detection is performed in the copy mode selected in step S410 (for example, copying is performed using recording paper of a set size).
[0059]
Whether or not to detect the document size by the prescan described above depends on the copy mode (copy type).
[0060]
It is assumed that the MFP according to the present embodiment can perform six types of copy modes as shown in FIG. That is, the copy modes (copy types) available in the MFP of the present embodiment are as follows.
[0061]
(1) Normal copy that simply copies the original
(2) Repetitive copy (manual) in which an original is repeatedly copied onto recording paper by the number of repetitions specified by the operator
(3) After performing pre-scanning to determine the size of the original, repeat copying to copy the original as often as possible on the recording paper (automatic)
(4) Mirror image copy in which the original is reversed and copied as if mirrored
(5) Full copy to copy the entire original in consideration of the printable area of the recording unit
(6) Automatic magnification copy, in which prescanning is performed and the original size is determined, the magnification is automatically determined, and the entire recording paper size is copied.
As described above, in the present embodiment, there are only two types of copies for which document size detection is performed by pre-scanning: (3) repetitive copying (automatic), and (6) automatic magnification copying.
[0062]
If the copy type is a repetitive copy (automatic) or an automatic magnification copy in which document size detection is performed, a prescan is performed prior to the reading process of an image used for actual copying to determine a document size.
[0063]
<Method of document size detection processing>
Next, a method of detecting a document size by pre-scan performed in the present invention will be described. Here, a method based on a line-based determination process and a method based on a pixel-based determination process are shown, and a method combining these line / pixel-based determination processes will also be described. One of the method based on the line-based determination processing and the method based on the pixel-based determination processing may be used independently, but a method combining the line / pixel-based determination processing as described later may be used. .
[0064]
In the following, an example is shown in which a document edge in the sub-scanning direction is searched, and then a document edge in the main scanning direction is searched. However, processing in which scanning direction is performed first is arbitrary.
[0065]
<Document size detection by line-by-line determination processing>
6 and 7 show a control procedure of document size detection by a line-by-line determination process performed in the prescan. The illustrated control procedure is executed by the CPU 101.
[0066]
In the processing of FIGS. 6 and 7, first, in step S601, various reading mode settings for prescan are performed.
[0067]
Regarding the setting in step S601, there is room for various settings in accordance with hardware characteristics and other conditions, but the following settings are made in the pre-scan of the present embodiment.
[0068]
First, whether document size detection should be performed using a color image or a monochrome image is required. If the read color data is set to full color, the amount of data is large, and the processing time and data analysis time are long. When the color data is set to monochrome, the data amount is small and the processing time and data analysis time are short, but since the gradation expression is poor, there is not much difference in the image data, and the possibility of erroneous detection is high. Therefore, in the present embodiment, the reading color mode is set to 8-bit gray scale.
[0069]
As for the reading resolution, the higher the resolution is set, the higher the accuracy is, but the longer the scanning time and the amount of data, the longer the processing time. Conversely, if the resolution is too low, the scan time will be short, but the accuracy will be reduced accordingly and the data volume will be small, making it impossible to compare. Therefore, in this embodiment, the reading resolution is set to 30 dpi.
[0070]
Further, with respect to the reading size at the time of pre-scanning, there is a gap in each part such as between the pressure plate and the document table due to the mechanical structure of the apparatus, and the gap may become a shadow when reading the document. For this reason, the density of the image data in this portion is reduced, and this may be erroneously detected as the document edge.
[0071]
Therefore, in the present embodiment, as shown in FIG. 10, the actual reading size (the outer range with the platen reference position 1005 at the upper right: the maximum range that can be read by the image sensor 204, or a range that allows for some margin) And an offset 1006 of 6.78 mm vertically and horizontally. During prescanning, the prescanning area 1001 smaller than the reading size that is read during actual normal copying is read and the image data of the original 1004 is stored. I do. Note that reference numeral 1002 in FIG. 10 denotes a rectangular range to be detected as the size of the document 1004 (the state of being placed obliquely is exaggerated), and reference numeral 1003 denotes a search position at the time of prescan (document size detection). Are shown.
[0072]
In the present embodiment, the reading color mode, the reading resolution, the reading size, and the like are set as described above as described above. However, since these values differ depending on the mechanical structure and characteristics of the apparatus, optimal values are set according to the apparatus. Needless to say, it is necessary to set, and the values described above in the present embodiment are not all.
[0073]
After performing the reading setting for performing the pre-scan in step S601, the image sensor 204 performs the pre-scan and stores the image data. Here, the number of lines of the sub-scanning lines read in the main scanning direction (hereinafter simply referred to as the number of lines in the main scanning direction) is m, and the number of main scanning lines arranged in the sub-scanning direction (hereinafter simply referred to as lines in the sub-scanning direction). The number is called n (step S602).
[0074]
Then, as shown in FIG. 8, the image data of the rear end in the sub-scanning direction, that is, the n-th line is obtained for one line (for example, the pixel data in the corresponding address range is extracted from the image memory in the DRAM 105 and is set as the line data). This data is used as reference line data in the sub-scanning direction (the direction of the arrow in FIG. 8 corresponds to the processing order starting from the n-th line). Similarly, the (n−1) th line is reference line data 1 in the sub-scanning direction, the (n−2) th line is reference line data 2 in the sub-scanning direction, and the (n−3) th line is reference line data 3 in the sub-scanning direction. S603).
[0075]
Then, the reference line data and the reference line data 1 are compared, and if the data change is 1% or more (step S604), the reference line data and the reference line data 2 are compared, and similarly, the data change is 1% or more. In this case (step S605), the reference line data is compared with the reference line data 3, and when the data change is 1% or more (step S606), the position of the line n is determined to be the document edge in the main scanning direction. (Step S609).
[0076]
Note that the “data change” here is, for example, a change in the density value of the document image data. In line-by-line comparison, a representative value (for example, a density average value) of two lines to be compared may be compared. The representative value (density average value, etc.) of each line data may be calculated every time steps S603 to S606 are passed, but the representative value once calculated for a certain line is cached in the memory area associated with that line. If the representative value of the same line becomes necessary, the value is used to improve the efficiency (the representative values of all the lines are calculated in advance before starting the processing of FIGS. 6 and 7). However, according to the present embodiment, it is highly unlikely that the document size detection process will be completed without scanning all the lines, so this method is not an advantage.)
[0077]
On the other hand, if there is no data change of 1% or more in the comparison between the reference line data and the reference line data 1, the comparison between the reference line data and the reference line data 2, and the comparison between the reference line data and the reference line data 3, n is decremented by one. (Step S607) The reference line data, the reference line data 1, the reference line data 2, and the reference line data 3 are shifted by one line and exchanged (Step S603).
[0078]
If the end of the original in the sub-scanning direction has not been determined even when n has become 4 (YES branch of step S608), it is determined that the original size cannot be detected. In this case, for example, it is determined that the document size is the maximum readable size of the mechanism (step S709 in FIG. 7).
[0079]
After the end of the original in the sub-scanning direction is determined, the end of the original in the main scanning direction is detected in the same manner as in FIG.
[0080]
The detection of the document edge in the main scanning direction in FIG. 7 is similar to the detection of the document edge in the sub-scanning direction. As shown in FIG. This is used as reference line data in the main scanning direction (the direction of the arrow in FIG. 9 corresponds to the processing sequence starting from the M line). However, the reference line data size in the main scanning direction used for comparison is the size up to the document end n in the sub-scanning direction determined previously, and a representative value of each line is calculated from the pixel data in this range, and the comparison is performed. And Similarly, the (m-1) th line is reference line data 1 in the main scanning direction, the (m-2) th line is reference line data 2 in the main scanning direction, and the (m-3) th line is reference line data 3 in the main scanning direction. S701).
[0081]
Then, the reference line data and the reference line data 1 are compared, and when the data change is 2% or more (step S702), the reference line data and the reference line data 2 are compared, and similarly, when the data change is 2% or more. In step S703, the reference line data and the reference line data 3 are compared. If the data change is 2% or more (step S704), the position of the line M is determined as the end of the document in the main scanning direction (step S704). Step S707).
[0082]
When comparing the reference line data with the reference line data 1, the reference line data with the reference line data 2, and the reference line data with the reference line data 3, if there is no data change of 2% or more, m is decremented ( In step S705, the reference line data, the reference line data 1, the reference line data 2, and the reference line data 3 are shifted by one line and exchanged (step S701).
[0083]
If the end of the original in the main scanning direction is not determined even when m is 4, (YES branch of step S706), it is determined that the original size cannot be detected, and the original size is set as the maximum readable size of the apparatus. (Step S709).
[0084]
As described above, the range 1002 in FIG. 10 can be detected as the document size. Since a plurality of lines are compared with the reference line in both the main scanning direction and the sub-scanning direction, it is possible to improve the reliability of detecting the document size even when the document 1004 is placed in an inclined state as shown in FIG. .
[0085]
In the above description, the case where the difference in data is 2% or more in the main scanning direction and 1% or more in the sub-scanning direction is regarded as the document edge. Value must be used as a reference. Furthermore, in the main scanning / sub-scanning directions, three lines (or more lines may be used) are set as a set with respect to the reference line, and the document edge is searched for. However, this is because accuracy / performance is considered. It is not always necessary to perform the comparison using the number of lines as a unit.
[0086]
When the edge of the document can be detected in both the main scanning direction and the sub-scanning direction, the reading size at the time of the pre-scan is smaller than the range at the time of the actual reading operation, that is, the offset 1006 is provided as shown in FIG. The final document size is determined in consideration of the fact that the prescan is performed (step S708: for example, the length of the offset 1006 is added in the main / sub-scanning directions, etc.).
[0087]
In the above case, when the edge of the original cannot be detected, the maximum readable size of the apparatus is set as the original size.However, such a process is not essential. The detected recording paper size may be used as the detection size, or the processing may be stopped without determining the document size and an error may be displayed.
[0088]
As described above, the original size is detected by the prescan, and the copy according to the selected copy mode can be executed using the determined original size information (step S406 in FIG. 4). For example, in the above-mentioned (3) repeated copying (automatic) and (6) automatic magnification copying, reading is performed only in the determined document size range, and the corresponding repeated copying or automatic magnification copying is executed.
[0089]
<Document size detection by pixel-based determination processing>
Next, the document size detection by the pixel-by-pixel determination process performed in the prescan will be described. In the document size detection by the pixel-by-pixel determination process performed in the pre-scan described below, the other hardware / software configuration and copy specifications are the same as those in FIGS.
[0090]
11 to 12 show a control procedure of document size detection by a pixel-by-pixel determination process performed in the pre-scan. The illustrated control procedure is executed by the CPU 101.
[0091]
Although the processing of step S601 in FIG. 6 is omitted in FIGS. 11 to 12 for simplicity, actually, the settings (color mode, resolution, offset of FIG. Settings, etc.) are performed in the same manner as the original size detection by the above-described line-by-line determination processing. However, in the document size detection by the pixel-by-pixel determination processing, it takes a long time to compare all the pixels, and the data accumulated in the gray scale of 30 dpi has a line interval of about 1 mm. The data comparison process is executed every other line in both the sub-scanning direction and the main scanning direction, assuming that it is within the error range (FIGS. 13 to 15 described later).
[0092]
After the reading setting for performing the pre-scan is performed, the pre-scan is executed by the image sensor 204 to accumulate the image data, and then the parameters are initialized. n is the image data size in the main scanning direction (units of pixels) accumulated by prescan, m is the image data size in the subscanning direction (units of pixels) accumulated by prescan, and "temporary document detected in main scanning direction". The “size”, “temporary document size detected in the sub-scanning direction”, “document size detected in the main scanning direction”, and “document size detected in the sub-scanning direction” are each initialized to 0 (step S1101).
[0093]
Here, the “temporary document size detected in the main scanning direction” and the “temporary document size detected in the sub-scanning direction” are the respective scanning directions that may be obtained by one-time determination of reference data and reference data. Of the original, the "original size detected in the main scanning direction" and the "original size detected in the sub-scanning direction" are the original sizes in the respective scanning directions finally determined by processing along one line described later. As will be described later, “the document size detected in the main scanning direction” and “the document size detected in the sub-scanning direction” are the “temporary document detected in the main scanning direction” obtained by the determination of the reference data and the reference data, respectively. If the "size" and the "temporary document size detected in the sub-scanning direction" are larger, they are updated with the values.
[0094]
In the loop of steps S1102 to S1110 in FIG. 11, the process starts with searching for the document edge in the sub-scanning direction. The following processing is performed for every other line in the sub-scanning direction.
[0095]
First, in step S1103, the image data size in the sub-scanning direction is substituted for v. That is, v is initialized to the image data size (pixel unit) m read in the sub-scanning direction.
[0096]
Next, in step S1104, after determining that v> 0 to form a loop until v becomes 0, as shown in FIG. 13, reference data and reference data are set to detect the document edge. . The reference data is the sum of the vth + (v + 1) th + (v + 2) th (v is an integer: the same applies hereinafter) pixel data (for example, a density value), and the reference data is the (v + 2) th + (v + 3) th + (v + 4). ) -Th pixel data (step S1105). Then, in step S1106, the difference between the reference data and the reference data is compared. If the difference is 10% or more, the v + 2th pixel (common pixel of the reference data and the reference data) is detected in step S1107. Original size ".
[0097]
Here, for the sake of simplicity, the numbers are counted as v-th, v + 1-th, v + 2-th... Of course, in the actual address calculation on the image memory, v, v-1, v-2. In some cases, the address of each pixel must be obtained in this way. Further, the display of the v-th, v + 1-th, v + 2... In FIG. 13 and FIG. 14 to be described later, and the display of the u-th, u + 1, u + 2. The v-th position is shifted one by one toward the (v + 1) -th side for each comparison, as will be apparent from the following description.
[0098]
Subsequent to step S1107, the “temporary document size detected in the sub-scanning direction” obtained in step S1107 is compared with the “document size detected in the sub-scanning direction” (initialized to 0 in step S1101) ( If the “temporary document size detected in the sub-scanning direction” is larger, the “document size detected in the sub-scanning direction” is replaced with this (step S1109).
[0099]
If the difference between the reference data and the reference data is not 10% or more in step S1106, the next reference data and reference data are set, and v is decremented by one pixel (step S1111). The process is repeated until the data difference becomes 10% or more or until the end of the line (steps S1104 to S1106, S1111). The same processing is performed when a position where the difference between the reference data and the reference data is 10% or more is detected (steps S1106 to S1108 to S1109) or the end of the line is detected (NO in step S1104). In order to perform processing every other line, n is decremented by −2 (step S1110), and the processing shifts to processing of the next line in the sub-scanning direction.
[0100]
Then, when the processing of all the data of the lines arranged in the sub-scanning direction is completed, it is determined whether the “document size detected in the sub-scanning direction” is 3 (minimum value) (step S1112). If the value is the minimum value, it is conceivable that the document size could not be detected or the document was not set on the platen. Therefore, an error warning notifying the fact (step S1213 in FIG. 12) was issued. Ends with a line. If the document size detected in the sub-scanning direction is not the minimum value, the value of “document size detected in the sub-scanning direction” is determined as the document size in the sub-scanning direction, and the search for the document edge in the main scanning direction in FIG. (The branch of B in FIG. 11).
[0101]
FIG. 14 shows a state of searching for the document edge in the sub-scanning direction. The dark pixels in FIG. 14 indicate the “temporary document size detected in the sub-scanning direction” obtained by changing the value of v for each line n, n−1,. As described above, the "document size detected in the sub-scanning direction" is initialized to 0 only once in step S1101, and thereafter, the largest value of the "temporary document size detected in the sub-scanning direction" shown in the figure. Therefore, the “document size detected in the sub-scanning direction” finally becomes the position of y in the figure.
[0102]
The search for the document edge in the main scanning direction in FIG. 12 is almost the same as the above-described search for the document edge in the sub-scanning direction.
[0103]
First, in step S1201, the values of m and n used in the above processing are initialized again to the corresponding original document data sizes in the scanning direction. Then, in step S1202, after the determination of m> 0 is made, the image data size in the main scanning direction is substituted for u in step S1203.
[0104]
In step S1204, u> 0 is determined in order to form a loop for processing one line, as in the case of v in FIG. 11. Then, in step S1205, the reference data and the reference data are used to detect the document edge. Set.
[0105]
That is, in step S1205, the reference data is the sum of the u-th + (u + 1) -th + (u + 2) -th pixel data (u is an integer), and the reference data is the (u + 2) -th + (u + 3) -th + (u + 4) -th Of pixel data (u is an integer). The meaning of the “u-th” is the same as the “v-th” described above. In the actual address calculation, unless the address of each “th” pixel is calculated as u, u−1, u−2. Not always.
[0106]
Note that the relationship between the reference data and the reference data in FIG. 13 shows the relationship between the reference data and the reference data as it is if all v in FIG. 13 are replaced with u.
[0107]
In step S1206, the difference between the reference data and the reference data is compared. If the difference is 10% or more, the position of the u + 2th pixel (a common pixel of the reference data and the reference data) is determined in step S1207 as "temporarily detected in the main scanning direction. In step S1208, the "temporary document size detected in the main scanning direction" is compared with the "document size detected in the main scanning direction", and if "detected in the main scanning direction" obtained in step S1207. If the "temporary document size" is larger, the "document size detected in the main scanning direction" is updated with this value (step S1209).
[0108]
On the other hand, if the difference between the reference data and the reference data is not 10% or more in step S1206, u is decremented by 1 in step S1211, and the next reference data and reference data are set. Is repeated until the position where the difference becomes 10% or more or until the end of the line (steps S1204 to S1206, S1211).
[0109]
The same processing is performed when a position where the difference between the reference data and the reference data is 10% or more is detected (steps S1206 to S1208 to S1209) or the end of the line is detected (NO in step S1204). In order to perform the processing for every other line, m is decremented by -2 (step S1210), and the processing shifts to processing of the next line in the sub-scanning direction.
[0110]
Then, when the processing of all data is completed, it is determined whether or not “document size detected in the main scanning direction” is 3 (minimum value) (step S1212). If the value is the minimum value, it is considered that the document size could not be detected or the document was not set on the platen, so an error warning notifying the fact (step S1213) is given and the processing is ended. I do. If the document size detected in the main scanning direction is not the minimum value, the value of "document size detected in the main scanning direction" is determined as the document size in the main scanning direction (D in FIG. 12). .
[0111]
FIG. 15 shows a state of searching for the document edge in the main scanning direction. The dark pixels in FIG. 15 indicate the “temporary document size detected in the main scanning direction” obtained by changing the value of u for each line m, m−1. As described above, the “document size detected in the main scanning direction” is initialized to 0 only once in step S1101, and thereafter, is increased to the largest value of the “temporary document size detected in the main scanning direction” in the figure. Since the document size is updated, the “document size detected in the main scanning direction” finally becomes the position of x in the figure.
[0112]
In this manner, the document size can be detected by the pixel-by-pixel determination processing. The obtained document size can be used in exactly the same manner as in the case of the above-described line-by-line determination processing.
[0113]
<Advantages of Document Size Detection by Line / Pixel Unit Determination>
In the above, the method of performing the determination / search processing in units of lines on the image data obtained by the prescan to detect the document size (FIGS. 6 to 10), and the method of performing the determination / search processing in units of pixels to obtain the document size (FIGS. 11 to 15), the original size detection according to the present invention has the following features. First, as a feature common to the above two methods,
(A) Simple and inexpensive without the need for a dedicated document size sensor
(B) High efficiency of detection processing
That is the point. In particular, the reason why the above two methods are highly efficient in the detection process as shown in FIG.
[0114]
(B1) A reference line (reference data) can be dynamically determined, and unnecessary processing such as scanning all image data a plurality of times to obtain a threshold is not required.
[0115]
(B2) The document size in the main / sub-scanning direction can be determined before searching for all the image data obtained by the pre-scan in either the line unit / pixel unit method. Moreover, in the line-by-line determination processing, when a document edge in one of the main / sub-scanning directions is detected, the number of pixels (line length) used in the subsequent detection of the document edge in the other direction is determined. ) Is further reduced. Further, in the pixel-by-pixel determination processing, the comparison of the reference data / reference data is performed every other line, so that the efficiency is high.
[0116]
<Document size detection combining line / pixel determination processing>
The above document size detection by the line-by-line determination process and the document size detection by the pixel-by-pixel determination process can be used independently, but both line / pixel unit determination processes are performed and the results are combined. May be used.
[0117]
FIG. 16 and FIG. 17 show a control procedure in the case where both determination processes are performed in line / pixel units and the results are used in combination.
[0118]
FIG. 16 shows an entire document size detection process including a document size determination process in the sub-scanning direction (step S1601) and a document size determination process in the main scanning direction (step S1602). This is the same as the entire flow of FIG. 7, or FIG. 11 or FIG.
[0119]
When the determination processing in line / pixel units is combined, the determination processing shown in FIG. 17 is performed in steps S1601 and S1602, and both the determination processing in line / pixel units is performed in each determination in the main / sub-scanning direction. Just combine the results.
[0120]
That is, in step S1701 of FIG. 17, the document size (document edge) L is detected by the line-by-line determination processing. In step S1701, the process of FIG. 6 is performed in the case of detecting the original size in the sub-scanning, and the process of FIG. 7 is performed in the case of detecting the original size in the main scanning.
[0121]
In step S1702, a document size (document edge) G is detected by a pixel-by-pixel determination process. In step S1702, the process of FIG. 11 is performed in the case of document size detection in the sub-scan, and the process of FIG. 12 is performed in the case of document size detection in the main scan.
[0122]
In step S1703, the original size (original edge) L is compared with the original size (original edge) G by the line-by-line determination process and the pixel-by-pixel determination process, and the larger L or G is determined as the final original size. It is detected (steps S1704, S1705).
[0123]
In this way, by combining the determination processing in line / pixel units, the accuracy of document size (document edge) detection can be improved.
[0124]
Note that FIG. 17 shows an example in which the larger document size (document edge) is used when combining the determination processing results in line / pixel units, but this combination is only an example and the hardware Any combination may be adopted according to the hardware configuration and specifications. Depending on the case, the smaller document size (document edge) may be adopted, or the average value of both may be used (a simple arithmetic average value or an average value obtained by adding a weight obtained based on some algorithm) Can also be adopted.
[0125]
<Association control of image reading method to image reading mode>
As described above, there are different image reading methods such as the ADF and the flatbed method, and a multi-function device such as an MFP is required to support these multiple reading methods, The reading mode is also required to support a plurality of different copy modes as shown in FIG. In each copy mode as shown in FIG. 5, different image reading modes such as an image reading mode in which a prescan is performed (for detecting a document size) and an image reading mode in which the prescan is not performed are at least used. No. In such a configuration that supports a plurality of image reading methods and image reading modes respectively, as described above, it is reliable only by selecting the image reading method and the image reading mode by manual operation (manual control) by the user. It is difficult to perform a reading process.
[0126]
Therefore, by performing the following association control between the image reading method and the image reading mode, it is possible to reduce the burden of a troublesome manual operation of the user and perform the reliable reading process.
[0127]
Hereinafter, an example will be described in which, in a configuration in which two image reading methods, that is, the ADF and the flatbed method, can be used, the association control between the image reading method and the image reading mode is performed.
[0128]
The hardware configuration (control system and operation panel) presupposed in the present embodiment is the same as that shown in FIGS. 1 and 3, and the image reading unit uses an ADF and a flatbed system as shown in FIG. It is assumed that the configuration is such that two image reading methods can be used.
[0129]
In FIG. 18, the ADF and the image reading unit of the flatbed system share some members (image sensor and black-and-white reference plate in the case of the present embodiment) except members related to document conveyance. In FIG. 18, a black-and-white reference plate 1810 is arranged below a document table 1807 and generates shading data of an image sensor 1806. The black-and-white reference plate 1810 is composed of two color portions, a white portion and a black portion. The image sensor 1806 is moved below the black-and-white reference plate 1810, and an illumination light source (not shown) of the image sensor 204 is provided below the image sensor 1806. By turning on or off, shading data of each color can be obtained.
[0130]
The document abutting position 1809 is a abutting position serving as a reference for arranging the leading end of the document serving as a reference for correctly stacking the documents on the document table 1807.
[0131]
The pressure plate 1811 is a lid for preventing external light from entering when reading a document, and the inside thereof is made of a white sheet.
[0132]
An image sensor 1806 is arranged below a document table 1807 made of transparent glass, scans a document 1808 on the document table 1807 by a driving unit (not shown), and reads an image thereof. When the apparatus is in a standby state (except when the ADF reading method is selected), the image sensor 1806 stands by at the image sensor home position 1805.
[0133]
The image sensor 1806 and the black-and-white reference plate 1810 are also used for reading using the ADF.
[0134]
The configuration of the above flatbed is almost the same as that shown in FIG. 2, but an ADF is arranged on the document table at one end of the flatbed. The ADF may be incorporated into the apparatus from the beginning, or may be configured to be detachable as an optional component.
[0135]
The ADF has a transport unit 1812 including rollers for transporting documents one by one from a document set position 1801 to a document discharge position 1803, and moves the image sensor 1806 to an ADF reading position 1804 below the transport unit 1812. The image of the automatically conveyed document can be read.
[0136]
A document detection sensor 1802 including an optical sensor and a limit switch is provided at the end of the document set position 1801 of the ADF. The document detection sensor 1802 can detect the presence or absence of a document on the document set position 1801.
[0137]
When the document detection sensor 1802 detects a document, it is assumed that the ADF reading method is selected, the flatbed reading method is not used, and a predetermined operation (such as the operation of the start key 309 in FIG. 3) is performed. ADF reading is performed.
[0138]
In the ADF reading, the image sensor 1806 is moved to the ADF reading position 1804, and while the document is being conveyed toward the document discharge position 1803, the image of that portion is read when the document passes over the ADF reading position 1804.
[0139]
When the document detection sensor 1802 has not detected a document (or by another explicit operation) and the ADF reading method has not been selected, the flatbed reading method is selected. If the flatbed reading method is selected, the image sensor 1806 returns to the image sensor home position 1805 and enters a standby state.
[0140]
In the configuration of the ADF reading unit as shown in FIG. 18, it is difficult to convey in the reverse direction by the conveying unit 1812 (even if possible, a complicated, expensive and impractical configuration is required). If the ADF reading method is selected, the prescan cannot be performed (for the purpose of detecting the size of a document).
[0141]
In the present embodiment, in the configuration of the reading unit as shown in FIG. 18, the image reading mode to the image reading mode associating control as shown in FIG. 19 is performed.
[0142]
FIG. 19 has an overall configuration substantially similar to that of FIG. 4 described above. In FIG. 19, steps having the same contents as those displayed in the 400s in FIG. 4 are denoted by step numbers in the 1900s, and detailed descriptions thereof are omitted except for particularly different steps.
[0143]
FIG. 19 differs from FIG. 4 in that steps S1904a and S1904b are inserted between step S1904 (S404 in FIG. 4) and step S1905 (S405 in FIG. 4).
[0144]
That is, in step S1904, it is determined that the document reading mode for detecting the document size by pre-scanning (in the copy mode of FIG. 5, (3) repetitive copy (automatic) and (6) automatic magnification copy) is selected. If it is determined in step S1904a, it is determined in step S1904a whether a document is set on the ADF (the ADF reading method is selected).
[0145]
If a document is set on the ADF in step S1904a (the ADF reading method is selected), an error warning is issued in step S1904b. That is, an affirmative determination in step S1904a means that the ADF reading method is selected in spite of the necessity of performing prescan (S1904), and a normal reading operation is not possible. In step S1904b, an error warning is issued to that effect. In step S1904b, an error warning is issued by visually displaying a message such as "Please remove the document from the ADF and select flatbed reading" on the display 317, or by outputting sound from a speaker.
[0146]
As described above, according to the present embodiment, a plurality of image reading methods (image reading means) such as the ADF method and the flatbed method, and an image reading mode (an image reading mode requiring a pre-scan and a pre-scan are required) If the image reading mode (image reading unit) and the image reading mode are in an inappropriate combination, the reading operation is prohibited, and the image reading unit and the image reading unit are disabled. The image reading process is prevented from being performed due to an improper combination of the image reading mode selection states, an error warning is issued, and the user is prompted to select an appropriate combination of the image reading method and the image reading mode. It can be guided reliably. In particular, according to the present embodiment, when a pre-scan is required, the function can be surely exerted in the image reading process, and the document size detection having the above-described many advantages in the pre-scan is performed. Using this document size detection result, it is possible to perform image reading with abundant functions.
[0147]
Further, the selection state of the image reading method (image reading means) can be detected simply and inexpensively and directly by detecting the presence or absence of a document at the document setting position 1801 of the ADF by the document detection sensor 1802. , The image reading mode to the image reading mode can be controlled. The method using the document detection sensor 1802 directly detects the presence or absence of a document at the document set position of the ADF, which can be easily visually determined by the user. Therefore, even if an error occurs, the user can easily detect the error. It can be understood.
[0148]
<About the modification>
As described above, various embodiments of the present invention have been described with respect to document size detection, image reading method to image reading mode association control, and the like. However, the present invention provides a plurality of devices (for example, a host computer, an interface device, a reader, and a printer). , Or a single-function device (for example, a copying machine, a facsimile machine, etc.).
[0149]
Further, which part (part or all) of the configuration of the present invention is configured by software / hardware of control means such as a microprocessor may be arbitrarily selected by those skilled in the art.
[0150]
Further, as for the software for realizing the present invention, a storage medium (recording medium) recording the program code of the software for realizing the functions of the above-described embodiments is supplied to a system or an apparatus, and the computer of the system or the apparatus (or Needless to say, the present invention can also be achieved by a CPU or an MPU) reading and executing the program code stored in the storage medium. In this case, the program code itself read from the storage medium realizes the function of the above-described embodiment, and the storage medium storing the program code constitutes the present invention. When the computer executes the readout program code, not only the functions of the above-described embodiments are realized, but also an operating system (OS) running on the computer based on the instruction of the program code. It goes without saying that a case where some or all of the actual processing is performed and the functions of the above-described embodiments are realized by the processing is also included in the embodiment of the present invention.
[0151]
Further, after the program code read from the storage medium is written into a memory provided in a function expansion card inserted into the computer or a function expansion unit connected to the computer, the function is executed based on the instruction of the program code. It is needless to say that the present invention includes a case where a CPU or the like provided in an expansion card or a function expansion unit performs part or all of actual processing, and the processing realizes the functions of the above-described embodiments. .
[0152]
The supply path of the software for realizing the present invention is arbitrary, and may be a path via a storage medium (recording medium) on which the program code is recorded, or a path via a network such as a LAN or WAN.
[0153]
【The invention's effect】
As is clear from the above description, according to the present invention, the document size of the document surface is detected from the image information obtained by pre-scanning the document surface for image reading prior to image reading, and In the image reading apparatus for performing image reading for controlling image reading on the original surface using the original size information, the control method thereof, and the control program, in the image reading apparatus, specific information in the image information obtained by the prescan is used as reference data. A search process is performed to compare with the information of the original document, and the original document size of the original surface corresponding to the image information is obtained without searching the entire image information obtained by the prescan. With a simple and inexpensive configuration that does not use sensors, there is no need for unnecessary processing such as scanning all image data multiple times to find a threshold, and searching for all image data High-efficiency and accurate acquisition of the document size before scanning, and even in a sophisticated and complex image reading system, the simple and inexpensive configuration enables efficient and accurate image reading processing. The effect is obtained.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a configuration of an MFP (Multi Function Peripheral) that employs the present invention.
FIG. 2 is an explanatory diagram showing a configuration of an image reading unit of the apparatus of FIG.
FIG. 3 is an explanatory diagram showing a configuration of an operation panel of the apparatus in FIG. 1;
FIG. 4 is a flowchart illustrating an image processing procedure of the apparatus of FIG. 1;
FIG. 5 is an explanatory diagram showing a copy mode supported by the apparatus of FIG. 1;
FIG. 6 is a flowchart illustrating a control procedure of document size detection by a line-by-line determination process according to the present invention.
FIG. 7 is a flowchart illustrating a control procedure of document size detection by a line-by-line determination process according to the present invention.
FIG. 8 is an explanatory diagram showing a state of a document edge search process in the process of FIG. 6;
FIG. 9 is an explanatory diagram showing a state of a document edge search process in the process of FIG. 7;
FIG. 10 is an explanatory diagram showing a search range of document size detection according to the present invention.
FIG. 11 is a flowchart illustrating a control procedure of document size detection by pixel-based determination processing according to the present invention.
FIG. 12 is a flowchart illustrating a control procedure of document size detection by a pixel-by-pixel determination process according to the present invention.
FIG. 13 is an explanatory diagram showing reference data and reference data in the processing of FIGS. 11 and 12;
FIG. 14 is an explanatory diagram showing a document edge search process in the process of FIG. 11;
FIG. 15 is an explanatory diagram showing a state of a document edge search process in the process of FIG. 12;
FIG. 16 is a flowchart illustrating a control procedure of document size detection in which determination processing in line / pixel units according to the present invention is combined.
FIG. 17 is a flowchart illustrating a control procedure of document size detection in which determination processing in line / pixel units according to the present invention is combined.
FIG. 18 is an explanatory diagram illustrating a configuration of a reading unit targeted for the association control between the image reading method and the image reading mode according to the present invention.
FIG. 19 is a flowchart illustrating a procedure for controlling the association between the image reading mode and the image reading mode according to the present invention.
[Explanation of symbols]
101 CPU
102 ROM
104 SRAM
106 Image Processor
107 Image sensor
108 Operation panel
109 Display
110 PC interface
111 PC
201 black and white reference plate
202 Document abutment position
203 pressure plate
204 Image Sensor
205 platen
301 Power key
302 Recovery key
303 Memory usage LED
304 Error display LED
305 Mode switch key
306 Color mode display LED
307 Color / monochrome switch key
308 stop key
311 Copy quality selection key
313 Recording paper size selection key
314 Copy magnification setting key
315 set key
316 Menu key
317 Display
1005 Platen reference position
1006 offset
1801 Original set position
1802 Original detection sensor
1804 ADF reading position
1805 Image sensor home position
1806 Image sensor
1807 Platen
1809 Original abutment position
1810 black and white reference plate
1811 pressure plate
1812 transportation means

Claims (15)

Prior to image reading, a document size of the document surface is detected from image information obtained by pre-scanning the document surface intended for image reading, and image reading of the document surface is controlled using the obtained document size information. In an image reading apparatus that performs image reading,
A search process is performed in which specific information in the image information obtained by the prescan is compared with other information as reference data, and a document surface corresponding to the image information without searching the entire image information obtained by the prescan. An image reading apparatus, comprising: a control unit that acquires a document size of a document. 2. The image reading apparatus according to claim 1, wherein the search processing is performed for each line of image information obtained by the prescan. 2. The image reading apparatus according to claim 1, wherein the search processing is performed for each pixel on image information obtained by the prescan. A document corresponding to the image information is obtained by performing the line-by-line and pixel-by-pixel search processing on image information obtained by the prescan, and combining the line-by-line search processing result and the pixel-by-pixel search processing result. The image reading apparatus according to claim 2, wherein an original size of a surface is acquired. 5. A document size of a document surface corresponding to the image information is determined based on a search process result having a larger size among the line-unit search process result and the pixel-unit search process result. An image reading device according to claim 1. Prior to image reading, a document size of the document surface is detected from image information obtained by pre-scanning the document surface intended for image reading, and image reading of the document surface is controlled using the obtained document size information. In a control method of an image reading device for reading an image,
A search process is performed in which specific information in the image information obtained by the prescan is compared with other information as reference data, and a document surface corresponding to the image information without searching the entire image information obtained by the prescan. A control method for an image reading apparatus, comprising a control step of acquiring a document size. 7. The control method according to claim 6, further comprising a control step of executing the search process on a line-by-line basis on image information obtained by the prescan. 7. The control method according to claim 6, further comprising a control step of executing the search processing on a pixel-by-pixel basis on image information obtained by the prescan. A document corresponding to the image information is obtained by performing the line-by-line and pixel-by-pixel search processing on image information obtained by the prescan, and combining the line-by-line search processing result and the pixel-by-pixel search processing result. 9. The control method for an image reading apparatus according to claim 7, further comprising a control step of acquiring a document size of a surface. A control step of determining a document size of a document surface corresponding to the image information based on a search process result having a larger size among the line-unit search process results and the pixel-unit search process results. The method for controlling an image reading device according to claim 9. Prior to image reading, a document size of the document surface is detected from image information obtained by pre-scanning the document surface intended for image reading, and image reading of the document surface is controlled using the obtained document size information. In a control program for an image reading device that performs image reading,
A search process is performed in which specific information in the image information obtained by the prescan is compared with other information as reference data, and a document surface corresponding to the image information without searching the entire image information obtained by the prescan. A control program for an image reading apparatus, comprising: a control step of acquiring a document size of a document. 12. The control program according to claim 11, further comprising a control step of executing the search processing on a line-by-line basis on image information obtained by the prescan. 12. The control program according to claim 11, further comprising a control step of executing the search process on a pixel-by-pixel basis on image information obtained by the prescan. A document corresponding to the image information is obtained by performing the line-by-line and pixel-by-pixel search processing on image information obtained by the prescan, and combining the line-by-line search processing result and the pixel-by-pixel search processing result. 14. The control program for an image reading apparatus according to claim 12, further comprising a control step of acquiring a document size of a surface. A control step of determining a document size of a document surface corresponding to the image information based on a search process result having a larger size among the line-unit search process results and the pixel-unit search process results. A control program for an image reading apparatus according to claim 14.

Images