JP3789534B2 - Image reading device - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to an image reading apparatus used for reading a document image and obtaining image data.
[0002]
[Prior art]
An example of a conventional image reading apparatus will be described. FIG. 8 is a block diagram showing the flow of image signals of a conventional image reading apparatus. The image sensor 71 scans the document and converts the reflected light from the document into an electrical signal. The A / D converter 72 converts the analog image signal from the image sensor 71 into a digital image signal. The image processing circuit 73 performs image processing and editing processing such as edge enhancement, trimming, halftone processing, pixel density conversion, and gradation number conversion on the digital image signal, and outputs image data. The buffer memory 74 buffers the image data from the image processing circuit 73. The CPU 85 includes RAM and ROM (not shown) and controls the entire image reading apparatus. The CPU 85, DMA controller 80, SCSI controller 81, and image processing circuit 73 are connected by a CPU bus 83.
[0003]
The DMA controller 80 DMA-transfers the image data stored in the buffer memory 74 to the SCSI controller 80. An external device such as a computer transmits a control command of the image reading apparatus to the image reading apparatus via the SCSI controller, and receives image data from the image reading apparatus. The CPU 85 sets an edge enhancement amount, the number of image data gradations, a reading density, and the like according to the image reading control command.
[0004]
[Problems to be solved by the invention]
A conventional image reading apparatus is connected to an external device such as a personal computer on a one-to-one basis using an interface such as SCSI. Therefore, the image reading apparatus is exclusively used by the user of the connected personal computer. When another user uses the image reading apparatus, it is necessary to reconnect the image reading apparatus to his / her personal computer or borrow an already connected personal computer. That is, there is a problem that the image reading apparatus is practically used exclusively by one user.
[0005]
In consideration of the problems of the conventional image reading apparatus, the present invention provides an image reading apparatus that can easily use the image input function of the image reading apparatus offline using a removable storage medium. It is the purpose.
[0006]
[Means for Solving the Problems]
In order to solve the above problems, an image reading apparatus according to the present invention includes an image sensor that converts optical information from an image reading target into an electrical signal, and an A / D converter that converts the electrical signal from the image sensor into a digital image signal. An image reading device comprising: image processing means for performing desired processing on the digital image signal and outputting image data; access means for accessing a removable storage medium ; and control means,
The control unit stores reading function information included in the image processing unit in the removable storage medium,
Further, the control means controls the image processing means based on reading control information generated by an external device based on reading function information stored in the storage medium and stored in the storage medium .
[0008]
In the present invention having such a configuration, software that can execute read control information (number of read gradations, read size, image compression method, edge enhancement amount, contrast, read density, image data file name, etc.) on a personal computer or the like. It is stored in a removable storage medium using wear. The user attaches the storage medium to the image reading apparatus of the present invention and sets a reading document on the image reading apparatus. The image reading apparatus of the present invention realizes an offline image input function by reading a document image in accordance with reading control information stored in the storage medium and storing the read image data in the storage medium. The user attaches the storage medium to the user's personal computer again, reads the stored image data, and performs desired processing.
[0009]
Further, the image reading apparatus of the present invention includes the above-described offline image input function in addition to a conventional one-to-one interface means with an external device. Accordingly, a user who frequently uses the image reading apparatus connects the image reading apparatus and his / her personal computer on a one-to-one basis, and a plurality of other users who are not using the image frequently use the offline image input function. A usage pattern in which a reader is used is possible.
[0010]
As described above, the image reading apparatus of the present invention has an offline image reading function, so that it can be shared by a plurality of users.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0012]
FIG. 1 is a block diagram showing the flow of image signals of the image reading apparatus of the present invention. In FIG. 1, the same components as those in FIG. 8 are given the same numbers. The configuration will be described together with the operation. The image sensor 71 scans the document and converts the reflected light from the document into an electrical signal. The A / D converter 72 converts an analog image signal (the electric signal) from the image sensor into a digital image signal. The image processing circuit 73 performs image processing and editing processing such as edge enhancement, trimming, halftone processing, tone number conversion, pixel density conversion, and the like on the digital image signal and outputs image data. The buffer memory 74 buffers the image data from the image processing circuit 73. The CPU 85 includes RAM and ROM (not shown) and controls the entire image reading apparatus. The CPU 85, PC card controller 87, DMA controller 80, SCSI controller 81, and image compression circuit 86 are connected by a CPU bus 83.
[0013]
The DMA controller 80 transfers the image data stored in the buffer memory 74 to the image compression circuit 86. The image compression circuit 86 compresses the image data transferred by the DMA controller 80 and generates compressed image data. The compressed image data is DMA-transferred to the SCSI controller 80 by the DMA controller 80. The compression method in the image circuit 86 is determined by the setting of the CPU 85 from a plurality of compression methods. An external device such as a computer transmits a control command of the image reading apparatus to the image reading apparatus via the SCSI controller 81 and receives compressed image data from the image reading apparatus. The CPU 85 sets an edge enhancement amount, the number of image data gradations, a reading density, and the like according to the image reading control command.
[0014]
The PC card controller 87 controls access from the CPU 85 to the memory card installed in the PC card slot 89. When a scan job command file in which reading control information is stored exists in a memory card mounted in the PC card slot 89, the image reading device reads a document image set based on the reading control information, and a compressed image Data is stored in the memory card as an image data file. After the user sets the original, the user presses a reading start button (not shown) to start reading the original. In the image reading apparatus, an image reading function and an image processing function such as whether or not an optional device such as an ADF (Auto Document Feeder) is mounted may vary depending on the configuration of the optional device. For this reason, the image reading apparatus of the present embodiment has a function of storing image reading function information provided as an image scanner in the memory card as an image reading function information file. Details of the offline image input function will be described later.
[0015]
FIG. 2 is a block diagram of the image processing circuit 73 of FIG. The gamma conversion circuit 31, the edge enhancement circuit 32, the pixel density conversion circuit 33, the trimming circuit 34, and the gradation number conversion circuit 35 are connected to the CPU bus 83, and the CPU 85 sets processing parameters for each circuit. The gamma conversion circuit 31 performs data conversion of an 8-bit digital image signal. The gamma conversion circuit 31 is a conversion table using a 256-byte RAM having an 8-bit address line. The RAM data is downloaded from the CPU 85. The CPU 85 can set the reading density and the contrast characteristic by changing the conversion table stored in the RAM.
[0016]
The edge enhancement circuit 32 performs edge enhancement processing of image data using a known two-dimensional spatial filtering technique. The CPU 85 can set the degree of edge enhancement in the edge enhancement circuit 32 by changing the filter coefficient of the spatial filter. The pixel density conversion 33 circuit performs pixel density conversion of image data by performing interpolation and thinning of the image data. The CPU 85 can set the pixel density of the output image data by changing the setting values of the interpolation rate and thinning rate of the pixel density conversion circuit 33.
[0017]
The trimming circuit 34 cuts out a desired rectangular area from the read image data. The CPU 85 can set the position and size of the cutout area by changing the set value of the cutout area. The gradation number conversion circuit 35 converts 8-bit (256 gradations) image data per pixel into N-bit image data. N, 1, 4 and 8 are selected by the CPU 85. When N is set to 1, simple binarization processing, dither processing, and error diffusion processing can be selected by the CPU 85 as binarization processing methods. When N is set to 4, the CPU 85 can select upper N-bit extraction, multi-level dither processing, and multi-level error diffusion processing as quantization methods. When N is set to 8, the gradation number conversion circuit 35 outputs 8-bit image data as it is. The gradation number conversion circuit 35 packs the image data subjected to the gradation number conversion into 8 bits and outputs it.
[0018]
FIG. 3 shows a connection configuration diagram between the image reading apparatus of this embodiment and an external device. The image reading device 20 and the personal computer 21 are connected one-to-one by a SCSI cable 22, and the user of the personal computer 21 can directly use the image reading device 20 online. Further, the image reading device 20 includes a PC card insertion slot 23, and a memory card 24 is detachable. The memory card 24 is also detachable from the notebook personal computer 25. Therefore, when the user of the personal computer 25 obtains document image data using the image reading device 20, the image data is transferred from the image reading device 20 to the personal computer 25 offline using the memory card 24.
[0019]
(Offline image input function)
An offline image input function in the image reading apparatus according to the present embodiment will be described.
The user attaches his / her memory card 24 to the image reading device 20 in advance and downloads the reading function information file to the memory card. The contents of the reading function information file are shown in FIG. The contents of the reading function information file shown in FIG. 4 will be described below.
[0020]
The format of the reading function information file is described as follows for each line.
[Function items] [List of selectable functions]
Or
[Function items] [Function capabilities]
Or
if [Selection condition] then [Function item] [List of selectable functions]
The first setting value written in the list of selectable functions is the default value.
[0021]
The meaning of each line of the reading function information file shown in FIG. 4 is shown below.
First line: A4, A4R, B4, A3, B5, and B5R can be set as the read document size, and the default is Auto. Auto is a mode for automatically detecting the document size.
Second line: The following three types of document placement methods can be specified. A document is fed from an ADF (Auto Document Feeder) and scanned until there is no scanned document (ADF). A single document placed on the document table is read (FlatBed). When a document is placed on the ADF, the document from the ADF is read. Otherwise, the document on the document table is read (Auto). The default is Auto.
Third line: The maximum value of the reading resolution is 1200 DPI.
4th line: indicates that the minimum value of the reading resolution is 25 DPI.
Line 5: Gray level (number of data bits per pixel) can be selected from 1, 4 and 8 bits, and the default value is 1 bit.
6th line: When gray level 1 is selected, one of binarization processing methods can be selected from simple binarization processing (BI), dither processing (DT), and error diffusion processing (ED). The default is a simple binarization process.
7th line: When the gray level is selected as 4, the quantization processing method can be selected from one of upper 4 bits extraction processing (SIMPLE), multilevel dither processing (DT), and multilevel error diffusion processing (ED). . The default is the upper 4 bits extraction process.
8th line: TIFF, BMP, JPEG can be selected as the image data file format, and the default is TIFF.
9th line: When TIFF is selected as the image data file format and 1 is selected as the gray level, the data compression method is G3 (MH), G4 (MMR), RLE (run length), NO (no compression) The default is G3.
10th line: When TIFF is selected as the image data file format and 4 is selected as the gray level, LZW or NO can be selected as the data compression method, and the default is LZW.
11th line: When TIFF is selected as the image data file format and 8 is selected as the gray level, LZW, JPEG or NO is selected as the data compression method. 12th line: JPEG is selected as the image data file format. Alternatively, when JPEG is selected as the compression method, Normal (normal compression ratio), High (high compression ratio), and LOW (low compression ratio) can be selected as the compression ratio, and the default is NORMAL. 13th line: When scanning, there is a contrast adjustment function, and Auto (automatic), -2 (low contrast) to 2 (high contrast) can be selected. The default is Auto.
14th line: There is a reading density adjustment function, and Auto (automatic), -2 (light) to 2 (dark) can be selected. The default is Auto.
15th line: When reading, there is a function of adjusting the edge enhancement amount, and Auto (automatic), -2 (weak edge enhancement) to 2 (strong edge enhancement) can be selected. The default is Auto.
16th line: A reading area can be specified. The default is a setting that does not specify a reading area (reads the entire document size).
17th line: The designated unit of the reading area is millimeter (mm).
[0022]
When the document image data is obtained offline using the image reading apparatus of the present embodiment, the user attaches the memory card 24 on which the reading function information file has been downloaded as described above to the user's personal computer 25. The user executes scan job command file creation software for the image reading apparatus that is installed in the personal computer 25 used by the user in advance. This software refers to the reading function information file stored in the memory card 24 and displays a dialog box for allowing the user to set the reading function of the image reading device 20 on the display of the personal computer 25. .
[0023]
FIG. 5 shows a schematic display of the dialog box corresponding to the reading function information file shown in FIG. In FIG. 5, a rectangular area on the right side of Scanning Resolusion, Scanning Area Position, Scanning Area Length, and Data File Name is an edit box. Enter each image data file name. The circles in the other rows are radio buttons that can be selected by alternative. ● indicates items that have been selected. In FIG. 5, since TIFF is selected as the image data file format and 1 is selected as the gray level, G3, G4, RLE, and NO are valid selection items for Compression. In the case of FIG. 5, since JPEG is not selected as the compression method and JPEG is not selected as the file format, the selection of the compression rate is invalid. Only when Scanning Area Setting is Yes, the settings for Scanning Area Upper-Left Position and Scanning Area Length are valid.
[0024]
The scan job command file creation software checks the MAXResolution and MINResolution values in the reading function information file, and warns the user if there is a conflict with the Scanning Resolution setting in the dialog box. Similarly, the user is also warned when the setting values of Paper Size (document size) and Scanning Area Upper-Left Position and Scanning Area Length conflict.
[0025]
After setting the items in the dialog box, the user clicks the OK button in FIG. The scan job command file creation software creates a scan job command file based on the setting in the dialog box and stores it in the memory card 24. FIG. 6 shows the contents of the scan job command file corresponding to the dialog box setting of FIG. The first line (Reset) of the scan job command file in FIG. 6 indicates that the reading function setting value is reset to the default value. In the DataFile section, the name of the image file that stores the read image data is described. In the case of FIG. 6, the image file name is sample.tif. In the image file, multi-page (multiple page) images are stored in one file. The scan job command file can combine a plurality of jobs into one file. That is, a plurality of read originals can be read with different reading function settings.
[0026]
FIG. 7 shows a flowchart of the process of the scan job command file creation software. According to this software, the reading function information file is read from the memory card 24 (step S1), and a reading function setting dialog box is displayed based on the reading function information file (step S2). After setting each setting item in the dialog box, the user clicks an OK button (step S3). This software checks whether there is a contradiction in the settings of the dialog box (step S4), displays a warning if there is a contradiction (step S5), and prompts the user to reset the dialog box. If there is no contradiction, a scan job command file is created (step S6) and stored in the memory card 24.
[0027]
Next, the user extracts the memory card 24 storing the scan job command file from the user's personal computer 25 and inserts it into the PC card slot 89 of the image reading apparatus 20. The CPU 85 in the image reading device 20 detects that the memory card 24 has been inserted via the PC card controller 87 and searches for a scan job command file on the memory card 24. If the scan job command file exists, the CPU 85 analyzes the scan job command file and makes necessary settings in the image processing circuit 73. The document image data read by the image sensor 71 is stored as an image data file in a memory card inserted into the PC card slot via the buffer memory 74, the image compression circuit 86, and the PC card controller 87.
[0028]
The user removes the memory card 24 in which the image data file is stored from the image reading device 20 and attaches it again to the user's personal computer 25. The user uses the image data stored in the memory card 24 using document creation / image editing software executed on the personal computer 25.
[0029]
As described above, when the image input function of the image reading apparatus of the present embodiment is used, document reading control data (scan job command file) is stored in a removable storage medium, and this storage medium is stored in the present embodiment. Attached to the image reading device. As a result, the image reading apparatus according to the present embodiment can output the read image data to the storage medium in a desired reading form offline, and can be shared by a plurality of users. Further, the user can easily create the read control data using the user interface of the personal computer. In particular, notebook computers are often not directly connected to external devices because they may be carried around. Even in such a case, according to the image reading apparatus of the present embodiment, it is possible to easily read an original image offline using a memory card or the like.
[0030]
Furthermore, since the image reading apparatus of the invention can download the image reading function information of the copying machine to the storage medium, the user can use all the image reading functions of the image reading apparatus.
[0031]
In the embodiment of the present embodiment, the removable storage medium is a memory card, but the same effect can be obtained even if it is a floppy disk, an optical disk, a removable hard disk, or the like. Further, in the embodiment, the case of a monochrome image reading apparatus has been described, but the same applies to the case of color. Furthermore, in the embodiment, the function information file and the job command file are character data files, but may be files encoded into binary data.
【The invention's effect】
As described above, in the image reading apparatus of the present invention, reading control data for image data of a document image is stored in a removable storage medium, and the storage medium is loaded into the image reading apparatus of the present invention for reading. Image data can be output off-line to the storage medium in a desired reading form. Therefore, this image reading apparatus can be shared by a plurality of users.
[0033]
Furthermore, since the image reading apparatus of the present invention can download the image reading function information of the image reading apparatus to the storage medium, the user can use all the image reading functions of the image reading apparatus.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a flow of an image signal in an embodiment of an image reading apparatus of the present invention. FIG. 2 is a block diagram of an image processing circuit 73. FIG. 3 is an image reading apparatus and an external device of the embodiment. [Figure 4] Contents of reading function information file [Figure 5] Outline display of dialog box for setting of reading functions [Figure 6] Contents of scan job command file [Figure 7] Creation of scan job command file FIG. 8 is a block diagram showing the flow of an image signal of a conventional image reading apparatus.
24 Memory card 71 Image sensor 72 A / D converter 73 Image processing circuit 81 SCSI controller 83 CPU bus 84 Page memory 85 CPU
86 Compression / Expansion Circuit 87 PC Card Controller 89 PC Card Slot

Claims (2)

An image sensor that converts optical information from an image reading target into an electrical signal, an A / D converter that converts an electrical signal from the image sensor into a digital image signal, and an image obtained by performing desired processing on the digital image signal An image reading apparatus comprising image processing means for outputting data, access means for accessing a removable storage medium , and control means,
The control unit stores reading function information included in the image processing unit in the removable storage medium,
Further, the control means controls the image processing means based on reading control information generated by an external device based on reading function information stored in the storage medium and stored in the storage medium . Image reading device. The image data is data compressed by coding, the image reading apparatus according to claim 1, characterized in that it comprises compression means for encoding the image data.

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