JP2013232844A - Image processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress increase in user's time and effort caused by using up of the free space of memory, in the case of storing acquired image data in the memory.SOLUTION: An image processing apparatus executes: feature-determination data storage processing which acquires, from image data acquired by acquisition processing, feature-determination data for determining the feature of the image data, and stores the feature-determination data in the memory; image data storage processing for storing, in the memory, the image data acquired by the acquisition processing; free space determination processing for determining whether there is a free space to store the image data in the memory; and invalidation processing for invalidating the feature-determination data storage processing, when it is determined that there is no free space in the free space determination processing.

Description

  The present invention relates to a technique for acquiring image data and storing it in a memory.

  Conventionally, a technique is known in which image data read from a document is stored in a storage unit and applied to a background detection unit, and the density of the background portion is detected based on the image data (for example, see Patent Document 1).

JP 2000-156762 A

By the way, when image data read from a document is stored in the storage unit as in the prior art, there is a problem that if the number of documents is large, there is no space in the storage unit in the middle and the document cannot be read any more. . In this case, the user has to read the document separately, which is troublesome for the user.
In the present specification, a technique for suppressing an increase in user's effort due to the vacant area of the memory when the acquired image data is stored in the memory is disclosed.

An image processing device disclosed in this specification includes an acquisition unit that acquires image data, a memory, and a processing unit, and the processing unit acquires the image data by controlling the acquisition unit. Processing, feature determination data storage processing for acquiring feature determination data for determining the characteristics of the image data from the image data acquired by the acquisition processing, and storing the data in the memory, and acquisition by the acquisition processing An image data storage process for storing the image data in the memory, a free area determination process for determining whether or not there is a free area for storing the image data in the memory, and a free area determination process. An invalidation process for invalidating the feature determination data storage process when it is determined that there is no free space;
Execute.

According to the image processing apparatus, the feature determination data is not stored in the memory when there is no free space in the memory, so that the image data that can be stored in the memory can be increased.
Therefore, according to the image processing apparatus, when the acquired image data is stored in the memory, it is possible to suppress an increase in time and effort of the user due to the absence of the memory free space.

  In the feature determination data storage process, the processing unit acquires the feature determination data from the image data for each feature and stores the feature determination data in the memory. In the invalidation process, the processing unit performs the free area determination process. Each time it is determined that there is no free space, the feature determination data storage process may be invalidated in stages.

  According to the image processing apparatus, the feature determination data storage process is invalidated step by step, so that all the image data can be stored without invalidating the feature determination data storage process more than necessary in the above case.

  Further, the processing unit acquires a feature determination data storage area for storing the feature determination data storage area for storing the feature determination data in the memory, and acquires the image data and stores it in the memory. The feature determination / storage process for repeatedly executing the process includes: an image data storage area securing process for securing an image data storage area for storing the image data in the memory; and the image data storage area securing process When the image data storage area is secured in the memory, the acquisition unit controls the acquisition unit to acquire the image data, and the feature determination data is acquired from the image data acquired by the acquisition process Acquired by the feature determination data storage process to be stored in the feature determination data storage area and the acquisition process. Storing the image data in the image data storage area; and storing the next image data in the memory after the image data is stored in the image data storage area by the image data storage process. The feature determination data storage process is invalidated when it is determined that there is no free area by the free area determination process for determining whether there is a free area to perform, and the free area determination process. The feature determination / storage process for repeatedly executing the invalidation process for releasing the feature determination data storage area may be executed.

  According to the image processing apparatus, when there is no free memory area, the feature determination data storage area is released, so that the image data that can be stored in the memory can be increased.

  In addition, the processing unit determines whether or not there is a free area for storing the image data in the memory before the image data storage area is first secured by the image data storage area securing process. In the image data storage area securing process, when the image data storage area is first secured in the image data storage area securing process, when it is determined that there is a free area in the initial free area judging process, the image data A storage area may be secured.

  For example, when acquiring image data for the first time, because the memory is used by other functions of the image processing apparatus, there is no case where the free space has already been exhausted when the image data storage area is first reserved. I can't say that. For this reason, it is desirable to determine whether or not there is a free area for storing image data in the memory before the image data storage area is secured for the first time.

  In addition, the processing unit analyzes the feature determination data stored in the feature determination data storage area to determine the feature of the image data, and the feature determined by the feature determination processing An image data processing process for processing the image data based on the image data, and in the image data storage process, the image data processed by the image data processing process is stored in the image data storage area, In the invalidation process, the feature determination process may be invalidated.

  According to the image processing apparatus, image data can be processed based on the determined characteristics.

  In addition, the processing unit is configured to determine a plurality of characteristics of the image data, and performs the feature determination process that differs depending on the determined characteristics. In the feature determination data storage area securing process, The feature determination data storage area is secured for each feature to be determined. In the feature determination data storage process, the feature determination data is acquired for each feature from the image data and stored in the feature determination data storage area. In the invalidation process, each time the free area determination process determines that there is no free area, the feature determination data storage process and the feature determination process are invalidated step by step and invalidated. The feature determination data storage area in which the feature determination data used by the converted feature determination process is stored may be released.

When a feature determination data storage area is secured for each feature to be determined, all image data can be stored by disabling only a part of the feature determination data storage process and the feature determination process and releasing the feature determination data storage area. In some cases.
According to the above image processing apparatus, the feature determination data storage process and the feature determination process are invalidated in stages, so that the feature determination data storage process and the feature determination process are invalidated more than necessary in the above case. All of the image data can be stored without doing so.

  The priority order of invalidation may be set for the plurality of feature determination processes, and the processing unit may invalidate the feature determination process having a higher priority first in the invalidation process.

  According to the image processing apparatus, by invalidating the feature determination process having a high priority of invalidation first, it is possible to reduce the influence of invalidating the feature determination process.

  Further, when the ratio of the image data processed by the image data processing is equal to or higher than a reference ratio, the feature determination processing that determines the feature used by the image data processing is functioning effectively. The processing unit may determine whether or not the feature determination process functions effectively in the invalidation process, and invalidate the feature determination process that does not function effectively first.

  According to the image processing apparatus, since the feature determination process that is not functioning effectively is invalidated first, the influence of invalidating the feature determination process can be reduced.

  In addition, a priority of invalidation is set for a plurality of the feature determination processes, and the processing unit determines whether the feature determination process functions effectively in the invalidation process. It may be determined in order from the feature determination process having a higher value.

  According to the image processing apparatus, when there are a plurality of feature determination processes that are not functioning effectively, the feature determination processes that are not functioning effectively are invalidated first from the feature determination processes that have a high priority of invalidation. be able to.

  The higher priority may be set for the feature determination process having a larger size of the feature determination data storage area used for feature determination.

  According to the image processing apparatus, since the feature determination process having a larger size of the feature determination data storage area is invalidated earlier, the image data that can be stored in the memory can be increased.

  The processing unit may execute a setting process for receiving the priority order setting from a user.

  According to the image processing apparatus, the user can set the order in which the feature determination process is invalidated.

  Further, when the feature determination process is invalidated by the invalidation process, the processing unit may acquire the image data having the maximum data amount within the obtainable range by controlling the acquisition unit.

When the feature determination process is invalidated, the user may process the image data by himself. In that case, if the number of colors of the acquired image data is small or the size is small, the user may not obtain the desired image data.
According to the above-described image processing apparatus, when the feature determination process is invalidated, the image data having the maximum data amount within the obtainable range is obtained, so that there is a high possibility that the user can obtain desired image data.

  In addition, when the feature determination process is invalidated by the invalidation process, whether the feature change determined before invalidation by the invalidated feature judgment process is below a reference change level Acquired after invalidation from a feature determined by the feature determination process before invalidation when it is determined by the feature change determination process and the feature change determination process that the level is not more than the reference change level. A feature estimation process for estimating the feature of the image data, and when acquiring the image data after invalidation in the acquisition process, the image data is acquired with a setting according to the feature estimated by the feature estimation process. Also good.

According to the above-described image processing apparatus, after invalidating the feature determination process, the influence of the feature determination process being invalidated can be reduced by acquiring image data with a setting according to the feature determined before the invalidation. .
Even after the feature determination process is invalidated, the image data processing process can be continuously executed.

  Further, the processing unit may execute a notification process for notifying a user that the invalidation process has been executed.

  According to the image processing apparatus, the user can know that the feature determination data is not stored in the memory.

  The acquisition unit may be an image reading unit that sequentially reads one or more documents and generates image data.

  According to the above-described image processing apparatus, it is possible to suppress an increase in time and effort required for the user to read a document due to the absence of a free memory area.

  The present invention can be realized in various modes such as an image processing system, an image processing method, an image processing program, and a recording medium on which the image processing program is recorded.

FIG. 2 is a schematic diagram illustrating a simplified configuration of an image reading unit according to the first embodiment. FIG. 3 is a block diagram showing an electrical configuration of the image reading apparatus. The data flow figure of a feature judgment / storage process. FIG. 4 is a schematic diagram illustrating a feature determination data storage process, a feature determination data storage area, a feature determination process, and an image data processing process. The flowchart of a characteristic judgment / storage process. 6 is a flowchart of one original reading process. 10 is a flowchart of empty area determination / invalidation processing. 10 is a flowchart of empty area determination / invalidation processing. 10 is a flowchart of empty area determination / invalidation processing according to the second embodiment. 10 is a flowchart of empty area determination / invalidation processing. 10 is a flowchart of empty area determination / invalidation processing. 10 is a flowchart of invalidation determination processing for automatically determining the number of colors. 9 is a flowchart of invalidation determination processing for document area extraction.

<Embodiment 1>
The first embodiment will be described with reference to FIGS.
(1) Configuration of Image Reading Unit First, an image reading unit 11 included in an image reading device 1 (see FIG. 2) as an image processing device according to the first embodiment will be described with reference to FIG. The image reading unit 11 is an example of an acquisition unit.

A housing 31 of the image reading apparatus 1 is formed in a box shape, and a first platen glass 32 and a second platen glass 33 are juxtaposed on the top.
The document cover 34 is connected to the casing 31 so as to be rotatable between a closed posture covering the platen glasses and an open posture of opening the platen glasses. The document cover 34 has a document tray 35 on which one or more documents are stacked, an ADF (Auto Document Feeder) 13 that transports documents stacked on the document tray 35 one by one, and a document transported by the ADF 13 is discharged. A paper discharge tray 37 for paper is provided.

  Inside the ADF 13, there are a separation roller 38, a suction roller 39, a conveyance roller 40, 41, a discharge roller that is rotatably provided at the distal end of an arm that is pivotally supported by the shaft that supports the separation roller 38. A paper roller 42 and a plurality of driven rollers 43 that are in pressure contact therewith are provided. The original is transported on the transport path T by these rollers, passes through a position where it is read by the reading device 15, and is discharged onto the discharge tray 37.

  The reading device 15 includes a light source composed of RGB RGB LEDs and the like, an image sensor in which a plurality of light receiving elements are linearly arranged in the direction perpendicular to the paper surface (main scanning direction), and reflected light reflected by the document. An optical system for forming an image on each light receiving element, a carriage on which these are mounted, and the like are provided.

The transport mechanism 14 includes a driving roller 45, a driven roller (not shown), a timing belt 46 wound around these, a stepping motor (not shown), and the like.
When reading a document placed on the first platen glass 32, the reading device 15 is transported by the transport mechanism 14 in the sub-scanning direction (A direction in the figure) parallel to the surface of the first platen glass 32, and the light source The document is read line by line while sequentially switching the colors of the images, and an image signal is output to the AFE 16 (see FIG. 2) described later.
On the other hand, when reading a document conveyed by the ADF 13, the reading device 15 is moved directly below the second platen glass 33 by the conveyance mechanism 14, and reads the document line by line while sequentially switching the color of the light source in the stopped state. Then, an image signal is output to the AFE 16 described later.

(2) Electrical Configuration of Image Reading Apparatus Next, the electrical configuration of the image reading apparatus 1 will be described with reference to FIG. The image reading apparatus 1 includes a control unit 10, an image reading unit 11, an image processing ASIC 17, a display unit 18, an operation unit 19, a communication interface unit 20, and the like.

  The control unit 10 includes a CPU 10a, a ROM 10b, a RAM 10c, and the like. The CPU 10a controls each unit of the image reading apparatus 1 by executing various programs stored in the ROM 10b. The ROM 10b stores a control program executed by the CPU 10a and various data. The RAM 10c is used as a main storage device for the CPU 10a to execute various processes. The RAM 10c is an example of a memory.

The image reading unit 11 includes a device control unit 12, an ADF 13, a transport mechanism 14, a reading device 15, and an AFE (Analog Front End) 16.
The device control unit 12 is an ASIC that controls the ADF 13, the transport mechanism 14, and the reading device 15 under the control of the control unit 10.
The AFE 16 is a circuit that performs gain adjustment of the image signal output from the reading device 15, A / D conversion for converting the gain-adjusted image signal into a digital image signal, and the like. In the following description, the A / D converted image signal is referred to as read data.

The image processing ASIC 17 is a circuit that reads the read data output from the AFE 16 and stored in the RAM 10c, performs gamma correction and shading correction, and generates image data having RGB three-color density values for each pixel. The image processing ASIC 17 has various image processing functions such as a blank sheet removal function, a skew correction function, an automatic color number discrimination function, and a document area extraction function, which will be described later, and performs image processing on the generated image data. The control unit 10 and the image processing ASIC 17 stored in the RAM 10c constitute a processing unit 9. Note that part or all of the image processing executed by the image processing ASIC 17 may be executed by the control unit 10. Conversely, part of the processing executed by the control unit 10 may be executed by the image processing ASIC 17.

  The display unit 18 includes a display device such as a liquid crystal display, a drive circuit that drives the display device, and the like.

The operation unit 19 has various buttons for the user to operate the image reading apparatus 1. The user can operate the operation unit 19 to set a reading condition when reading a document or to instruct reading of the document.
As the scanning conditions, the number of scanning colors, the document size, the above-described blank sheet removal function validity / invalidity, the skew correction function validity / invalidity, and the like can be set.

  Color, monochrome, black and white, or automatic can be set as the number of read colors. When automatic is set, reading is performed in color, and then the number of colors is automatically determined by the image reading apparatus 1, and the data amount of the image data is reduced according to the determined number of colors. In the present embodiment, it is assumed that the automatic color number discrimination function is valid when automatic is set for the number of read colors, and the automatic color number discrimination function is invalid when other than automatic is set.

  The size of the document to be read or automatic can be set as the document size. When automatic is set, the original is read at the maximum readable size, and then the original size is detected by the image reading apparatus 1, and the original area is extracted from the image data according to the detected original size. In the present embodiment, it is assumed that the document area extraction function is valid when the document size is set to automatic, and the document area extraction function is disabled when other than automatic is set. When other than automatic is set, the document size is not detected, and an area having a size corresponding to the set size is extracted as the document area. The description of the extraction of the document area when other than automatic is set is omitted in this embodiment.

The communication interface unit 20 is an interface for communicating with an external device such as a PC (personal computer) via a communication network such as a LAN (Local Area Network), a USB (Universal Serial Bus), a parallel line, or the like.
When the image reading apparatus 1 reads a document and generates image data, the image data is stored in the RAM 10c. When transmission of image data is requested from the PC, the image data is transmitted to the PC via the communication interface unit 20.

(3) Data Flow of Feature Judgment / Storage Processing Next, an outline of the feature judgment / storage processing executed by the CPU 10a and the image processing ASIC 17 will be described with reference to the data flow diagram shown in FIG. The feature determination / storage process is a process of repeatedly executing a process of acquiring image data and storing it in the RAM 10c. However, FIG. 3 shows only a part of the process repeatedly executed by the feature determination / storage process.
Here, the image data temporary storage area 81, the feature determination data storage area 82, the compression waiting data storage area 83, and the image data storage area 84 shown in FIG. 3 are all storage areas secured in the RAM 10c. To do.
Further, when the image processing ASIC 17 generates image data, the image data is converted from the RGB color space to the YCbCr color space and stored in the image data temporary storage area 81.

  The free space determination / invalidation process 52 shown in FIG. 3 is a process executed by the CPU 10a. In addition to this, the CPU 10a performs a feature determination data storage area securing process for securing the feature judgment data storage area 82 in the RAM 10c, and an image data storage area for securing the image data storage area 84 for storing one image data in the RAM 10c. The securing process, the acquisition process for controlling the image reading unit 11 to acquire the read data, the feature change determination process, the feature estimation process, and the like are also executed. A description of processing not shown in FIG. 3 will be given later.

  The feature determination data storage process 51, the feature determination process 53, the image data processing process 54, and the compression / image data storage process 55 are processes executed by the image processing ASIC 17.

Hereinafter, each process shown in FIG. 3 will be described.
The feature judgment data storage process 51 acquires feature judgment data for judging the feature of the image data from the image data stored in the image data temporary storage area 81 and stores it in the feature judgment data storage area 82. It is processing to do. The feature determination data may be extracted from image data or may be image data itself.

The feature judgment process 53 is a process for judging the feature of the image data by analyzing the feature judgment data stored in the feature judgment data storage area 82.
The image data processing 54 reads out the image data stored in the image data temporary storage area 81, processes the image data based on the feature determined by the feature determination processing 53, and compresses the processed image data. This is a process of storing in the waiting data storage area 83.

  When there are a plurality of image data processing processes 54, the image data processing process 54 executed first returns the image data to the image data temporary storage area 81 after the processing, and the image data processing process 54 executed last is an image. It is assumed that data is stored in the compression waiting data storage area 83.

The compression / image data storage process 55 is a process of compressing the image data stored in the compression-waiting data storage area 83 in a predetermined compression format such as the Jpeg format, and storing the compressed image data in the image data storage area 84. It is.
The free area determination / invalidation process 52 determines whether or not there is a free area for storing image data in the image data storage area 84, and if there is no free area due to a large number of documents, This is a process of invalidating the judgment data storage process 51, the feature judgment process 53, and the image data processing process 54 and releasing the feature judgment data storage area 82. Invalidating a process means not executing the process.

  If the feature determination data storage process 51, the feature determination process 53, and the image data processing process 54 are invalidated by the free area determination / invalidation process 52, the image data stored in the image data temporary storage area 81 is stored. Is stored in the compression waiting data storage area 83 by the CPU 10a.

(4) Details of Feature Judgment Data Storage Processing, Feature Judgment Processing, and Image Data Processing Processing Next, referring to FIG. 4, feature judgment data storage processing 51, feature judgment processing executed by the image processing ASIC 17 53 and the image data processing 54 will be described more specifically.
The image processing ASIC 17 determines a plurality of characteristics of the image data, and executes a characteristic determination data storage process 51, a characteristic determination process 53, and an image data processing process 54 that differ depending on the determined characteristics. As shown in the figure, the feature determination data storage area 82 is secured for each feature determination process 53.

  Hereinafter, the feature determination data storage process 51, the feature determination process 53, and the image data processing process 54 will be described for each image processing function of the image processing ASIC 17.

(4-1) Blank Page Removal Function The blank page removal function is a blank page determination process 53a for determining whether or not an image represented by image data is a blank page, and when the blank page determination process 53a determines that the page is blank. This function executes a blank paper removal process 54a for removing data. Blank paper is an example of the characteristics of image data.
Whether or not the sheet is blank is determined by using the value of the Y component of the image data converted into the YCbCr color space. Specifically, the image processing ASIC 17 that executes the blank sheet removal feature determination data storage process 51a performs blank sheet removal feature determination using only the Y component of the image data represented in the YCbCr color space as blank sheet removal feature determination data. The data is stored in the data storage area 82a. Then, the image processing ASIC 17 that executes the blank page determination process 53a determines that the page is blank if the ratio of the pixels whose Y component value in the blank sheet removal feature determination data is equal to or greater than a predetermined value.

(4-2) Skew Correction Function The skew correction function determines whether or not the document area representing the document is inclined on the image represented by the image data, in other words, whether or not the document has been read in a skewed state. This function executes a skew determination process 53b to be performed, and a skew correction process 54b to correct the inclination of the image data when it is determined by the skew determination process 53b that the image is read while being skewed.

  Whether or not the original is read in a skewed state is determined using the Y component value of the image data converted into the YCbCr color space. Specifically, the image processing ASIC 17 that executes the skew correction feature determination data storage process 51b performs skew correction using only the Y component of the image data represented in the YCbCr color space as skew correction feature determination data. Stored in the feature determination data storage area 82b. Then, the image processing ASIC 17 that executes the skew determination process 53 b detects an edge representing the side of the document using the value of the Y component of the skew correction feature determination data, and the detected edge is detected by the image reading apparatus 1. An angle inclined with respect to a direction corresponding to the main scanning direction is determined. Then, the image processing ASIC 17 determines that the document is skewed if the tilt angle is other than 0 degrees. The tilted angle is an example of the characteristics of the image data.

(4-3) Automatic Color Number Discriminating Function The automatic color number discriminating function is an automatic color number discriminating process 53c for judging whether the color number of the image represented by the image data is color, monochrome or black and white, and the judged color. This is a function for executing a data amount reduction process 54c for reducing the amount of image data according to the number. The number of colors is an example of the characteristics of image data.

  The automatic determination of the number of colors is performed using image data converted into the YCbCr color space. Specifically, the image processing ASIC 17 that executes the color number automatic determination feature determination data storage process 51c automatically determines the number of colors as the image data expressed in the YCbCr color space as it is as the color number automatic determination feature determination data. Stored in the feature determination data storage area 82c.

  The image processing ASIC 17 that executes the automatic color number determination process 53c determines the number of colors by using the Y, Cb, and Cr components of the image data. The image processing ASIC 17 that executes the data amount reduction processing 54c does not reduce the data amount of the image data when the number of colors is color. On the other hand, when the number of colors is monochrome, the image processing ASIC 17 deletes the Cb and Cr components from YCbCr, thereby reducing the data amount of the image data to about ３. When the number of colors is black and white, the image processing ASIC 17 further binarizes the density value of each pixel to 0 or 1, thereby reducing the amount of data compared to the case of monochrome.

(4-4) Document Area Extraction Function The document area extraction function uses a size detection process 53d for detecting the document size and an area corresponding to the document size detected by the size detection process 53d from the image represented by the image data as a document area. This is a function for executing the document area extraction processing 54d to be extracted. The document size is an example of the characteristics of image data.

  The document size is detected using the Y component value of the image data converted into the YCbCr color space. Specifically, the image processing ASIC 17 that executes the document area extraction feature determination data storage process 51d extracts the document area using only the Y component of the image data represented in the YCbCr color space as the document area extraction feature determination data. Stored in the feature determination data storage area 82d. Then, the image processing ASIC 17 that executes the size detection process 53d detects the document size by detecting the edges representing the four sides of the document using the Y component value of the document area extraction feature determination data.

(5) Flow of Feature Judgment / Storage Processing Next, the processing executed by the CPU 10a in the feature judgment / storage processing will be described more specifically with reference to FIG. Note that the processing executed by the image processing ASIC 17 in the feature determination / storage processing is as described in the above-described data flow of the feature determination / storage processing, and thus description thereof is omitted here. The feature determination data storage area securing process is not included in the feature determination / storage process, but the feature determination data storage area securing process is also described here.
This process is started when the user operates the operation unit 19 to instruct reading of a document. Here, it is assumed that the user has set a plurality of documents on the ADF 13 and instructed reading.

  In S101, the CPU 10a refers to the reading conditions set by the user, so that at least one of the blank sheet removal function, the skew feeding correction function, the color number automatic discrimination function, and the document area extraction function is valid. Judge whether or not. If there is any valid function, the CPU 10a proceeds to S102, and if any function is invalid, proceeds to S103.

In S102, the CPU 10a secures a feature determination data storage area 82 in the RAM 10c for each effective function. S102 is an example of a feature determination data storage area securing process.
In S103, the CPU 10a secures an image data storage area 84 for one image data in the RAM 10c. It is assumed that the size of the storage area secured as the image data storage area 84 is a size that can store image data having a size obtained by compressing image data generated by reading a document in accordance with reading conditions. For example, when the automatic color number discrimination function and the document area extraction function are enabled, the size estimated as the size when the image data generated by reading the document with color and the maximum readable size is compressed It is assumed that the image data is a size that can be stored.

In S104, the CPU 10a executes a process for reading one original.
In S105, the CPU 10a determines whether or not there is a next document. If there is, the process proceeds to S106, and if not, the process proceeds to S109.

In S106, the CPU 10a executes a free space determination / invalidation process 52.
As will be described in detail later, in the free area determination / invalidation processing 52, the feature determination data storage area 82 is released even when there is a free area for storing image data or when there is no free area. In this case, a value “ON” indicating that there is an empty area is set in an empty area flag, which is a variable indicating the presence or absence of an empty area.

In S107, the CPU 10a determines whether or not there is a free area by referring to the above-mentioned free area flag. If there is a free area, the process returns to S103, and if not, the process proceeds to S108.
In S108, the CPU 10a notifies the user that reading of the document is stopped by displaying a message on the display unit 18 that the reading of the document is stopped due to memory full.

In S109, the CPU 10a transmits the image data stored in the RAM 10c to the PC.
In S110, the CPU 10a discards all the image data stored in the image data storage area 84, and releases the image data storage area 84. Note that only the read image data may be transmitted to the PC.

(6) One Original Reading Process Next, the one original reading process executed in S104 described above will be described with reference to FIG.
In S201, the CPU 10a sets the number of reading colors when reading the document. The number of read colors is used as a control parameter when the device control unit 12 controls the reading device 15 to read a document.
Specifically, the CPU 10a sets the color as the read color number when the automatic color number discrimination function is enabled, and sets the read color number when the automatic color number discrimination function is disabled. Set the number of colors.

  In S202, the CPU 10a sets the document size when reading the document. Specifically, the CPU 10a sets the maximum size as the document size when the document area automatic extraction function is enabled, and sets the document size set by the user when the document size automatic detection is disabled. To do.

In S203, the CPU 10a controls the device control unit 12 to read one document. S203 is an example of an acquisition process.
In S204, the CPU 10a determines whether at least one of the blank sheet removal function, the skew feeding correction function, the color number automatic determination function, and the document area extraction function is effective, and even one of the functions is effective. If there is, the process proceeds to S205, and if any of the functions is invalid, the process ends and returns.

  In S205, the CPU 10a controls the image processing ASIC 17 to execute the feature determination data storage processing 51, the feature determination processing 53, and the image data processing processing 54 for effective functions, and to execute the compression / image data storage processing 55. .

(7) Free Space Judgment / Invalidation Processing Next, with reference to FIGS. 7 and 8, the free space judgment / invalidation processing 52 executed in S106 will be described.
In S301, the CPU 10a sets a value “OFF” indicating that there is no empty area as an initial value in the empty area flag.

In S302, the CPU 10a determines whether or not there is a free area for storing one image data in the RAM 10c. If there is not, the process proceeds to S303, and if there is, the process proceeds to S322.
In S303, the CPU 10a determines whether or not the blank paper removal function is valid. If it is valid, the process proceeds to S304, and if it is invalid, the process proceeds to S308.

In S304, the CPU 10a releases the blank paper removal feature determination data storage area 82a.
In S305, the CPU 10a invalidates the blank paper removal function. Specifically, the CPU 10a invalidates the blank sheet removal feature determination data storage process 51a, the blank sheet determination process 53a, and the blank sheet removal process 54a.

In S306, the CPU 10a notifies the user that the blank sheet removal function has been disabled by displaying a message indicating that the blank sheet removal function has been disabled on the display unit 18. S306 is an example of notification processing.
In S307, the CPU 10a sets a value “ON” indicating that there is a free space in the free space flag.

S308 to S312 are substantially the same as the processes of S303 to S307 except that the blank sheet removal function of S303 is replaced with a skew feeding correction function.
S313 to S317 are substantially the same as the processes of S303 to S307 except that the blank sheet removal function of S303 is replaced with an automatic color number discrimination function.
S318 to S322 are substantially the same as the processes of S303 to S307 except that the blank sheet removal function of S303 is replaced with the document area extraction function.

(8) Effects of the embodiment When the empty area of the RAM 10c runs out while a plurality of originals are being read, the reading of the originals can no longer be continued. In that case, the user has to divide the document into the number of images that can be stored in the RAM 10c and perform the reading operation again, which increases the user's trouble.
On the other hand, according to the image reading apparatus 1 according to the first embodiment, when storing the image data and the feature determination data for determining the characteristics of the image data in the RAM 10c, if the RAM 10c has no empty area, the image reading apparatus 1 is empty. Since the feature determination data storage area 82 is released by the area determination / invalidation processing 52, the image data that can be stored in the RAM 10c can be increased. Thereby, it is possible to continue reading the document as much as possible. Therefore, according to the image reading apparatus 1, it is possible to suppress an increase in user's effort due to the vacant area of the RAM 10c being lost.

  Further, according to the image reading apparatus 1, the feature determination processing 53 that analyzes the feature determination data to determine the feature of the image data, and the image data processing that processes the image data based on the feature determined by the feature determination processing 53 Since the process 54 is executed, the image data can be processed based on the determined characteristics.

  Furthermore, according to the image reading apparatus 1, since the user is notified that the invalidation processing has been executed, the user can know that the feature determination data is not stored in the RAM 10c.

<Embodiment 2>
Next, Embodiment 2 will be described with reference to FIGS.
In the empty area determination / invalidation process 52 according to the first embodiment, when it is determined in S302 that there is no empty area, the blank sheet removal function, the skew feeding correction function, the color number automatic determination function, and the original area extraction function are all invalidated Accordingly, a blank paper removal feature judgment data storage area 82a, a skew correction feature judgment data storage area 82b, a color number automatic judgment feature judgment data storage area 82c, and a document area extraction feature judgment data storage area. The case where all of 82d are released has been described as an example. On the other hand, in the second embodiment, the feature determination processing 53 is invalidated step by step, and the feature determination data storage processing 51 and the image data processing processing 54 are also invalidated step by step, and the feature determination data storage is performed. The area 82 is gradually opened. That is, the image processing function is invalidated step by step.

(1) Priority of Invalidation of Feature Judgment Processing A plurality of methods can be considered as a method for determining the invalidation order when the feature judgment processing 53 is invalidated step by step. An example is shown below.

(Decision Method 1) Determination Based on Priority Order This is a method in which the priority order of invalidation is set in the feature judgment process 53, and the feature judgment process 53 having a higher priority order is invalidated first. As a method of setting the priority order of invalidation, for example, the order in which the size of the feature determination data storage area 82 is large can be used. If the amount of feature determination data is large, a large amount of free space is created when the feature determination processing 53 is invalidated. For this reason, for example, if the feature determination processing 53 having the largest amount of feature determination data is invalidated, and all the image data can be stored thereby, only one feature determination processing 53 need be invalidated. Therefore, it is not necessary to invalidate the feature determination process 53 unnecessarily.

  The priority order of invalidation may be set on the basis of the degree of disadvantage for the user when invalidation is performed. For example, it can be said that the user's disadvantage when the blank paper removal process 54 a is invalidated compared to the other feature determination process 53 is small. This is because even if blank image data is included in the image data, it can be said that there is not much inconvenience for the user.

  The priority order of invalidation may be set by the user operating the operation unit 19. The process in which the CPU 10a controls the operation unit 19 and receives the setting of the invalidation priority order from the user is an example of a setting process.

(Determination Method 2) Determination Based on Effective Feature Judgment Processing When the rate at which image data has been processed by the image data processing processing 54 is greater than or equal to the reference rate, feature determination processing for determining the features used by the image data processing processing 54 When 53 is functioning effectively, the feature determination processing 53 that is not functioning effectively is invalidated first.

For example, if a blank page is determined by the blank page determination process 53a, the image data is processed because it is deleted by the blank page removal process 54a. If it is not determined, the image data is not processed. Become.
If the ratio of the image data determined to be blank by the blank page determination process 53a is large, the ratio of the processed image data is increased. Therefore, it can be said that the blank page determination process 53a functions effectively. On the contrary, when the ratio of the image data determined to be blank is small, it can be said that the blank sheet determination processing 53a does not function effectively because the ratio of the processed image data is small.

  Similarly, when the ratio of image data in which the document is determined to be tilted by the skew determination process 53b is large, the ratio of image data in which skew correction is corrected by the skew correction process 54b is increased. It can be said that the determination process 53b functions effectively. On the contrary, when the ratio of the image data determined to be skewed is small, it can be said that the skew determination processing 53b does not function effectively. The same applies to the automatic color number discrimination process 53c and the size detection process 53d.

  When there is a feature determination process 53 that functions effectively and a feature determination process 53 that does not function effectively, it is less disadvantageous for the user to disable the feature determination process 53 that does not function effectively first. For this reason, if the feature determination processing 53 that does not function effectively is invalidated first, the feature determination processing 53 can be invalidated while suppressing an increase in the user's disadvantage.

(Decision Method 3) Determination Based on Combination of Invalidation Priority and Effective Feature Judgment Processing For example, assume that the invalidation priority of feature judgment processing 53 is set as follows.

Invalidation priority 1: Blank page determination process 53a
Invalidation priority order 2: skew determination processing 53b
Invalidation priority 3: Color number automatic discrimination processing 53c
Invalidation priority 4: Size detection processing 53d

  In this case, first, it is determined whether or not the blank page determination process 53a, which is the feature determination process 53 with the highest priority of invalidation, is functioning effectively. If it is not functioning effectively, the blank page determination process 53a is disabled. It becomes.

  On the other hand, when the blank page determination process 53a is functioning effectively, the blank page determination process 53a is a process having the highest invalidation priority, but is not invalidated, and has the next highest invalidation priority. It is determined whether or not the skew determination process 53b, which is a process, is functioning effectively. If the skew determination process 53b does not function effectively, the skew determination process 53b is invalidated. That is, the skew determination process 53b is a function having a lower priority of invalidation than the blank sheet determination process 53a, but is invalidated before the blank sheet determination process 53a. The same applies to the color number automatic discrimination processing 53c and the size detection processing 53d.

Here, even when the priority order is determined by combining the priority order of invalidation and the valid feature determination process 53, it is not necessarily determined for all the feature determination processes 53 whether or not the function is functioning effectively. It does not have to be.
For example, it is determined whether or not the blank paper removal process 54a and the skew determination process 53b function effectively, and the automatic color number determination process 53c and the size detection process 53d function effectively. You may make it not judge. In this case, when both the blank paper removal process 54a and the skew feeding determination process 53b are functioning effectively, the invalidation priority is lower than the blank paper removal process 54a and the skew feeding judgment process 53b. The automatic color number determination process 53c and the size detection process 53d, which are the determination processes 53, are invalidated.

(2) Document reading when feature determination processing is disabled Since the feature cannot be determined when the feature determination processing 53 is disabled, an image whose image data is processed based on the feature determined by the feature determination processing 53 Data processing 54 is also invalidated. In this case, when the feature of the image data after invalidation can be estimated from the tendency of the feature determined before invalidation by the invalidated feature determination processing 53, the image reading unit 11 is used using the estimated feature. You may make the original read.

  For example, in the case of automatic color number discrimination processing 53c, when the monochrome or gray judgment ratio up to the previous document is 90% or more, the image data after invalidating the color number automatic discrimination processing 53c is also monochrome or gray. It is possible to cause the image reading unit 11 to read the document with the gray setting after the automatic color number discrimination processing 53c is invalidated.

  Similarly, in the case of the size detection process 53d, for example, if the size determination result up to the previous document is 90% or more of the same standard size, the document size after the size detection process 53d is invalidated is also the standard size. After presuming that there is a size and invalidating the size detection process 53d, the image reading unit 11 may read the document with the standard size setting.

  However, it is not always necessary to estimate the characteristics of the image data after invalidation for all functions. For example, the feature may be estimated only for the number-of-colors automatic discrimination processing 53c and the size detection processing 53d, and the image reading unit 11 may read the document.

(3) Free Space Judgment / Invalidation Processing Next, free space judgment / invalidation processing 52 according to the second embodiment will be described with reference to FIGS. 9, 10, and 11.
Here, “(determination method 3) determination based on a combination of invalidation priority and valid feature determination processing” of the above-described methods for determining the invalidation priority of the feature determination processing 53 will be described as an example. . Specifically, it is assumed that the priority of invalidation of the feature determination process 53 is set as follows.

Invalidation priority 1: Blank page determination process 53a
Invalidation priority order 2: skew determination processing 53b
Invalidation priority 3: Color number automatic discrimination processing 53c
Invalidation priority 4: Size detection processing 53d

  Whether or not the function is functioning effectively is determined only for the blank sheet determination process 53a and the skew determination process 53b, and the color number automatic determination process 53c and the size detection process 53d are functioning effectively. No judgment will be made.

  For the automatic color number discrimination processing 53c and the size detection processing 53d, the feature of the image data after invalidation is estimated, and the feature of the image data after invalidation is estimated from the tendency of the feature determined before invalidation. If possible, it is assumed that the image reading unit 11 reads the document with settings according to the estimated characteristics.

  Further, here, substantially the same processes as those in the free area determination / invalidation process 52 according to the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

In S401, the CPU 10a refers to the reading conditions set by the user to determine whether or not the blank sheet removal function is valid. If valid, the process proceeds to S402, and if invalid, the process proceeds to S406.
In S402, the CPU 10a determines whether or not the blank page determination process 53a is functioning effectively. Specifically, the CPU 10a determines whether or not the ratio of image data determined to be blank up to the previous document is 70% or more, and if it is less than 70%, the CPU 10a determines that it is not functioning effectively. The process proceeds to S403, and if it is 70% or more, it is determined that the function is effective, and the process proceeds to S406. 70% is an example of a reference ratio.

In S403, the CPU 10a releases the blank paper removal feature determination data storage area 82a.
In S404, the CPU 10a invalidates the blank paper removal function. Specifically, the CPU 10a invalidates the blank sheet removal feature determination data storage process 51a, the blank sheet determination process 53a, and the blank sheet removal process 54a.
In S405, the CPU 10a notifies the user that the blank sheet removal function has been invalidated. After the notification, the CPU 10a proceeds to S319.

In S406, the CPU 10a determines whether or not the skew correction function is valid. If it is valid, the process proceeds to S407, and if it is invalid, the process proceeds to S411.
In S407, the CPU 10a determines whether or not the skew determination process 53b is functioning effectively. Specifically, the CPU 10a determines whether or not the ratio of the image data determined to be skewed up to the previous document is 70% or more. If it is less than 70%, the CPU 10a determines that the image data is not functioning effectively. The process proceeds to S408, and if it is 70% or more, it is determined that the function is effective, and the process proceeds to S411. 70% is an example of a reference ratio.

In S408, the CPU 10a releases the skew correction feature determination data storage area 82b.
In S409, the CPU 10a invalidates the skew feeding correction function. Specifically, the CPU 10a invalidates the skew correction feature determination data storage process 51b, the skew determination process 53b, and the skew correction process 54b.
In S410, the CPU 10a notifies the user that the skew determination function has been invalidated. After the notification, the CPU 10a proceeds to S319.

  In S411, the CPU 10a determines whether or not the automatic color number determination process 53c is valid. If it is valid, the process proceeds to S412. If it is invalid, the process proceeds to S413.

In S412, the CPU 10a executes an invalidity determination process for automatically determining the number of colors.
In S413, the CPU 10a determines whether or not the document area extraction function is valid. If it is valid, the process proceeds to S414, and if it is invalid, the process proceeds to S413.
In S414, the CPU 10a executes a document area extraction invalidation determination process.

  S415 to S418 are processes that take into consideration the case where none of the feature determination processes 53 is invalidated in the processes of S401 to S414. If none of the feature determination processes 53 is invalidated in the processes of S401 to S414, the CPU 10a secures an empty area even if it is determined in S402 that the blank sheet determination process 53a is functioning effectively. Disable the blank page judgment function. Since S415 to S418 are the same processes as S401 and S403 to S405, the corresponding step numbers of S401 and S403 to S405 are added after the step numbers, and description thereof is omitted.

  S419 to S422 are also processes in consideration of the case where none of the feature determination processes 53 is invalidated in the processes of S401 to S418. If none of the feature determination processes 53 is invalidated in the processes of S401 to S418, none of the feature determination processes 53 is invalidated at the time of S419. For this reason, even if it is determined in S407 that the skew correction process 54b is functioning effectively, the CPU 10a disables the skew correction function in order to secure an empty area. Since S419 and S420 to S422 are the same processes as S406 and S408 to S410, the corresponding step numbers of S406 and S408 to S410 are attached after the step numbers, and the description thereof is omitted.

(4) Color Number Automatic Determination Invalidation Determination Process Next, the color number automatic determination invalidation determination process executed in S412 will be described with reference to FIG.
In S501, the CPU 10a releases the color number automatic discrimination feature determination data storage area 82c.

In S502, the CPU 10a invalidates the automatic color number discrimination function. Specifically, the CPU 10a invalidates the color number automatic determination feature determination data storage processing 51c, the color number automatic determination processing 53c, and the data amount reduction processing 54c.
In step S503, the CPU 10a determines whether the feature of the image data after invalidation can be estimated from the tendency of the feature determined before invalidation by the color number automatic discrimination processing 53c. Specifically, the CPU 10a determines whether or not the ratio of the image data determined as monochrome or gray up to the previous document is less than 90%, and determines that the feature cannot be estimated if it is less than 90%. The process proceeds to S504, and if it is 90% or more, the process proceeds to S505 because the feature can be estimated.
If it is 90% or more, it means that the change of the feature is small, so that the change of the feature is below the reference change level. S503 is an example of a feature change determination process and a feature estimation process.

In step S504, the CPU 10a sets the number of reading colors when the image reading unit 11 reads a document to color. In other words, the CPU 10a is set to acquire image data having the maximum data amount within an acquirable range.
The reason for setting the read color number to color is that the image data with the largest number of colors is stored for the sake of safety because it cannot be determined whether the color number of the image data is color, monochrome, or black and white.
More specifically, for example, even if a monochrome document is read in color, the user can later convert it to monochrome by processing image data on a PC. On the other hand, if the original is a color original when read in monochrome, it is difficult to process the image data into a color later. In other words, even if it takes time to process the image data later if it is read in color, the user can surely obtain the image data of the desired number of colors, so that the image data of the desired number of colors can be reliably obtained. It can be said that it is safe in the sense that it can.

  In S505, the CPU 10a determines whether or not the ratio of the image data determined to be gray up to the previous document is 90% or more. If it is 90% or more, the process proceeds to S506, and if it is less than 90%. The process proceeds to S507.

In S506, the CPU 10a sets the number of read colors to gray.
In S507, the CPU 10a sets the number of reading colors to monochrome.
In step S <b> 508, the CPU 10 a notifies the user that the color number automatic discrimination function has been invalidated and the read color number setting has been changed.

(5) Document Area Extraction Invalidation Determination Process Next, the document area extraction invalidation determination process executed in S414 will be described with reference to FIG.

In step S601, the CPU 10a releases the document area extraction feature determination data storage area 82d.
In S602, the CPU 10a invalidates the document area extraction function. Specifically, the CPU 10a invalidates the document area extraction feature determination data storage process 51d, the size detection process 53d, and the document area extraction process 54d.

In S603, the CPU 10a determines whether the feature of the image data after invalidation can be estimated from the tendency of the feature determined before invalidation by the size detection process 53d. Specifically, the CPU 10a determines whether or not the size determination result up to the previous document is 90% or more of the same standard size, and if it is less than 90%, the CPU 10a determines that the feature cannot be estimated and S604. If it is 90% or more, it is determined that the feature can be estimated, and the process proceeds to S605.
If it is 90% or more, it means that the change of the feature is small, so that the change of the feature is below the reference change level. S603 is an example of a feature change determination process and a feature estimation process.

In S604, the CPU 10a sets the document size when the image reading unit 11 reads the document to the maximum size. In other words, the CPU 10a is set to acquire image data having the maximum data amount within an acquirable range.
The reason for setting the document size to the maximum size is to store the image data having the largest size for the sake of safety because the region to be extracted as the document region cannot be specified from the image represented by the image data.

  More specifically, if the document size is set to the maximum size, the user can later extract the actual document region by processing the image data on the PC. On the other hand, if the document size is reduced, the image represented by the image data may not include a part of the document area. In this case, the entire document area is extracted even if it is later processed on the PC. I can't. That is, if the user reads the maximum size, the user can surely obtain the document area even if it takes time to process the image data later, so that the image data representing the image including the entire document area can be reliably obtained. It can be said that it is safe in meaning.

In S605, the CPU 10a sets the document size to the same standard size.
In S606, the CPU 10a notifies the user that the document area extraction function has been invalidated and that the document size setting has been changed.

According to the image reading apparatus 1 according to the second embodiment described above, the feature determination data storage process 51 and the feature determination process 53 are invalidated step by step each time it is determined that there is no free space. The feature determination data storage area 82 in which the feature determination data used by the converted feature determination processing 53 is stored is released.
When the feature determination data storage area 82 is secured for each feature, only a part of the feature determination data storage processing 51 and the feature determination processing 53 is invalidated, and the feature determination data corresponding to the feature determination data storage processing 51 If the storage area 82 is released, all image data may be stored. According to the image reading apparatus 1, the feature determination data storage processing 51 and the feature determination processing 53 are invalidated step by step. In such a case, the feature determination data storage processing 51 and the feature determination processing 53 are invalidated more than necessary. All image data can be stored without conversion.

  Furthermore, according to the image reading apparatus 1, since the feature determination processing 53 that is not functioning effectively is invalidated first, the influence of invalidating the feature determination processing 53 can be reduced.

  Further, according to the image reading apparatus 1, the priority order of invalidation is set in the plurality of feature judgment processes 53, and whether or not the feature judgment process 53 is functioning effectively is determined by the feature judgment process having a higher priority order. Since there are a plurality of feature determination processes 53 that are not functioning effectively, among the feature determination processes 53 that are not functioning effectively, the feature determination process 53 with the highest priority of invalidation is performed first. Can be disabled.

  Note that a higher priority may be set for the feature determination processing 53 having a larger size of the feature determination data storage area. In that case, since the feature determination processing 53 having a larger feature determination data storage area is invalidated earlier, the image data that can be stored in the memory can be increased.

  In addition, invalidation priority settings may be received from the user. In that case, the user can set the order in which the feature determination processing 53 is invalidated.

  Further, according to the image reading apparatus 1, when the color number automatic discrimination processing 53c is invalidated, the color is set as the number of read colors, so that it is highly possible that the user can obtain desired image data. The same applies to the document area extraction processing 54d.

  Further, according to the image reading apparatus 1, when the feature determination process 53 is invalidated, the feature of the image data acquired after invalidation is estimated from the feature determined by the feature determination process 53 before invalidation, and the invalidation is performed. When the original is later read by the image reading unit 11, it is read with a setting according to the estimated feature, so that the influence of invalidating the feature determination process 53 can be reduced.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and the drawings, and for example, the following embodiments are also included in the technical scope.

  (1) In the above embodiment, the image reading apparatus 1 is described as an example of the image processing apparatus. On the other hand, the image processing apparatus sequentially receives a plurality of image data from the PC, determines the characteristics, processes the image data based on the determined characteristics, stores the image data in the RAM 10c, and stores all the image data in the RAM 10c. It may be a printer that starts printing after the printing. Also in this case, if the number of image data is large, the RAM 10c has no free space and cannot be stored. Therefore, the feature determination processing 53 is invalidated and the feature determination data storage area 82 is released to allow the PC user to do so. There is a high possibility that all image data can be printed without redoing the printing operation.

  The image processing apparatus may be a FAX apparatus that stores image data generated by reading a document in the RAM 10c, and transmits all the image data to the external facsimile (FAX) apparatus after the image data is stored in the RAM 10c. .

  (2) In the second embodiment, “(determination method 3) determination based on a combination of invalidation priority and valid feature determination processing” is described as an example of a method for determining the order in which feature determination processing is invalidated. . However, the method of determining the invalidation order is not limited to this, and can be determined as appropriate.

  For example, whether or not the feature of the image data after invalidation can be estimated from the tendency of the feature determined before invalidation by the invalidated feature determination processing 53 is determined in the order of invalidating the feature determination processing 53. It may be used. Specifically, in the case of the feature determination processing 53 that can estimate the feature of the invalidated image data, the influence of the invalidation can be reduced by reading the document using the estimated feature. it can. Therefore, the feature determination processing 53 that can estimate the feature of the invalidated image data may be invalidated first.

  Further, the invalidation order may be determined by combining the priority order of invalidation and whether or not the feature of the invalidated image data can be estimated. Specifically, for example, it is determined whether or not the feature of the invalidated image data can be estimated in order from the feature determination processing 53 having the highest priority of invalidation. If the feature cannot be estimated, the feature determination processing 53 is not invalidated. . Then, it is determined whether or not the feature of the invalidated image data can be estimated for the feature determination processing 53 having the next highest priority for invalidation. If the feature determination processing 53 can be estimated, the next feature determination processing 53 is invalidated. In this case, the next feature determination process 53 is a feature determination process 53 having a lower priority of invalidation than the first feature determination process 53, but is invalidated before the first feature determination process 53. When the feature of the image data after invalidation can be estimated together with the first feature judgment processing 53 and the next feature judgment processing 53, the first feature judgment processing 53 is invalidated first. Become.

  (3) In the above embodiment, the case where the image data storage area 84 is secured in the RAM 10c has been described as an example of securing one image data at a time. In contrast, a plurality of pieces of image data may be secured, for example, two pieces of image data.

  (4) In the above-described embodiment, the case where the feature determination process 53 and the image data processing process 54 are executed has been described as an example. However, these processes may not be executed. In that case, for example, the PC that has received the image data may execute the feature determination process 53 and the image data processing process 54. The feature determination process 53 may be executed by the image reading apparatus 1, and the image data processing process 54 may be executed by a PC.

(5) In the above embodiment, in the feature determination / storage process, it is not determined whether there is an empty area in the RAM 10c between S101 and S102, but the same determination as S107 is performed between S101 and S102. Steps may be performed. If it is determined in that step that there is no free space, the process may proceed to S108. This step is an example of the first free area determination process.
In some cases, the step may be executed before S101 because there is no case where there is no free area at the time of securing the feature determination data storage area 82.

  (6) In the above embodiment, the image reading apparatus 1 that reads one side of a document is described as an example of the image processing apparatus. However, the image reading apparatus 1 may read both sides of a document. In that case, the image data storage area 84 for one side may be secured, or the image data storage area 84 for two sides may be secured.

(7) In the above embodiment, the case where the feature determination data storage area 82 is secured for each feature determination process 53 has been described as an example. On the other hand, two or more feature determination processes 53 may share one feature determination data, the feature determination data storage area 82, and the feature determination data storage process 51.
For example, the blank page determination process 53a, the skew feeding determination process 53b, and the size detection process 53d all determine a feature using the Y component of the image data. The data storage processing 51 is secured, and the Y component of the image data is stored in the feature determination data storage processing 51 by the shared feature determination data storage processing 51, and each feature determination processing 53 uses the data for each feature. May be judged.
Further, for example, the skew determination process 53b and the size detection process 53d detect an edge from the Y component of the image data. Therefore, the feature determination data storage process 51 is shared only for these two feature determination processes 53, and the feature determination is performed. The image data storage process 51 may store an image (so-called differential image) representing an edge indicating the side of the document on the image represented by the image data.

In the above-described embodiment, the case has been described as an example where the color number automatic discrimination feature determination data storage area 82c is secured in order to store the color number automatic discrimination feature determination data used by the color number automatic discrimination processing 53c. On the other hand, the color number automatic determination processing 53c may determine the feature using image data represented in the YCbCr color space stored in the image data temporary storage area 81. In this case, the feature number determination data storage area 82c for automatically determining the number of colors becomes useless.
However, the color space of the image data stored in the image data temporary storage area 81 is not necessarily the YCbCr color space. The color space of the image data stored in the image data temporary storage area 81 may vary depending on the reading conditions even for the model of the image reading apparatus or the same model. For example, when image data expressed in the RGB color space is stored in the image data temporary storage area 81, the color number automatic discrimination feature judgment data storage area 82c is separately required.

  (8) In the above embodiment, only the image represented in the YCbCr color space and the Y component of the image are described as feature determination data. However, arbitrary data is used as the feature determination data depending on the feature to be determined. be able to.

DESCRIPTION OF SYMBOLS 1 ... Image reading apparatus, 10 ... Control part, 10a ... CPU, 10b ... ROM, 10c ... RAM, 11 ... Image reading part, 17 ... Image processing ASIC, 18 ... Display unit, 19 ... Operating unit, 20 ... Communication interface unit, 51 ... Feature judgment data storage process, 52 ... Free space judgment / invalidation process, 51 ... Feature judgment Data storage processing, 51a... Feature determination data storage processing for blank paper removal, 51d... Document area extraction feature determination data storage processing, 51c... Color number automatic determination feature determination data storage processing, 51b ... Skew correction feature judgment data storage processing, 53 ... Feature judgment processing, 53a ... Blank paper judgment processing, 53b ... Skew judgment processing, 53c ... Color number automatic discrimination processing, 53d: Size detection processing, 54 Image data processing 54a: Blank sheet removal processing 54b Skew correction processing 54c Data amount reduction processing 54d Document area extraction processing 55 ... Compression / Image data storage Processing 81... Image data temporary storage area 82... Feature determination data storage area 82 a. Blank paper removal feature determination data storage area 82 b... Skew correction feature determination data storage Area, 82c... Feature judgment data storage area for automatic color number discrimination, 82d... Document area extraction feature judgment data storage area, 83... Compression waiting data storage processing, 84. region

Claims (15)

An acquisition unit for acquiring image data;
Memory,
A processing unit;
With
The processor is
An acquisition process for acquiring the image data by controlling the acquisition unit;
Feature determination data storage processing for acquiring feature determination data for determining the characteristics of the image data from the image data acquired by the acquisition processing and storing the data in the memory;
Image data storage processing for storing the image data acquired by the acquisition processing in the memory;
A free space determination process for determining whether or not there is a free space for storing the image data in the memory;
An invalidation process for invalidating the feature determination data storage process when it is determined by the free area determination process that there is no free area;
An image processing apparatus that executes The image processing apparatus according to claim 1,
In the feature determination data storage process, the processing unit acquires the feature determination data for each feature from the image data and stores the feature determination data in the memory.
In the invalidation process, the feature determination data storage process is invalidated step by step whenever it is determined by the free area determination process that there is no free area. The image processing apparatus according to claim 1,
The processor is
A feature judgment data storage area securing process for securing a feature judgment data storage area in the memory for storing the feature judgment data;
A feature determination / storage process that repeatedly executes a process of acquiring the image data and storing it in the memory,
An image data storage area securing process for securing an image data storage area in the memory for storing the image data;
The acquisition process of controlling the acquisition unit to acquire the image data when the image data storage area is reserved in the memory by the image data storage area ensuring process;
The feature determination data storage processing for acquiring the feature determination data from the image data acquired by the acquisition processing and storing the feature determination data in the feature determination data storage area;
The image data storage process for storing the image data acquired by the acquisition process in the image data storage area;
The free area determination process for determining whether or not there is a free area for storing the next image data in the memory after the image data is stored in the image data storage area by the image data storage process; ,
Invalidating the feature determination data storage process and releasing the feature determination data storage area when the free area determination process determines that there is no free area; and
Judgment / storage process of repeatedly executing
An image processing apparatus that executes The image processing apparatus according to claim 3,
The processor is
Before the first image data storage area is secured by the image data storage area securing process, an initial free area determination process is performed to determine whether or not there is a free area for storing the image data in the memory. ,
In the image data storage area securing process, when the image data storage area is secured first, the image data storage area is secured when it is determined by the initial free area judgment process that there is a free area. apparatus. The image processing apparatus according to claim 3 or 4,
The processor is
A feature determination process for determining the characteristics of the image data by analyzing the feature determination data stored in the feature determination data storage area;
Image data processing for processing the image data based on the features determined by the feature determination processing;
Run
In the image data storage process, the image data processed by the image data processing process is stored in the image data storage area,
An image processing apparatus that further invalidates the feature determination process in the invalidation process. The image processing apparatus according to claim 5,
The processing unit is configured to determine a plurality of characteristics of the image data, and performs the feature determination process that differs depending on the characteristics to be determined.
In the feature determination data storage area securing process, the feature determination data storage area is secured for each feature to be judged,
In the feature determination data storage process, the feature determination data is acquired for each feature from the image data and stored in the feature determination data storage area,
In the invalidation process, each time the free area determination process determines that there is no free area, the feature determination data storage process and the feature determination process are invalidated in stages and invalidated. An image processing apparatus that releases the feature determination data storage area in which the feature determination data used by the feature determination processing is stored. The image processing apparatus according to claim 6,
A plurality of feature determination processes are set with a priority of invalidation,
In the invalidation process, the processing unit invalidates the feature determination process having the higher priority first. The image processing apparatus according to claim 6,
When the ratio of the image data processed by the image data processing is equal to or higher than the reference ratio, the feature determination processing that determines the characteristics used by the image data processing is functioning effectively.
In the invalidation process, the processing unit determines whether or not the feature determination process functions effectively, and invalidates the feature determination process that does not function effectively first. The image processing apparatus according to claim 8,
A plurality of feature determination processes are set with a priority of invalidation,
The image processing apparatus, wherein the processing unit determines, in the invalidation process, whether or not the feature determination process is functioning in order from the feature determination process having the highest priority. The image processing apparatus according to claim 7 or 9, wherein
The image processing apparatus in which the higher priority is set for the feature determination processing in which the size of the feature determination data storage area used for feature determination is larger. The image processing apparatus according to claim 7 or 9, wherein
The image processing apparatus, wherein the processing unit executes a setting process for receiving a setting of the priority order from a user. An image processing apparatus according to any one of claims 5 to 11,
When the feature determination process is invalidated by the invalidation process, the processing unit controls the obtaining unit to obtain image data having a maximum data amount within an acquirable range. An image processing apparatus according to any one of claims 5 to 12,
The processor is
A feature change determination that determines whether or not the change in the feature determined before the invalidation by the invalidated feature determination process is equal to or lower than a reference change level when the feature determination process is invalidated by the invalidation process. Processing,
Feature estimation for estimating the feature of the image data acquired after invalidation from the feature judged before invalidation by the feature judgment processing when the feature change judgment processing judges that the level is below the reference change level Process and execute
In the acquisition processing, when acquiring the image data after invalidation, an image processing device that acquires the image data with settings according to the features estimated by the feature estimation processing. An image processing apparatus according to any one of claims 1 to 13,
The said processing part is an image processing apparatus which performs the alerting | reporting process which alert | reports to a user that the said invalidation process was performed. An image processing apparatus according to any one of claims 1 to 14,
The acquisition unit is an image processing apparatus that is an image reading unit that sequentially reads one or more originals to generate image data.

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