JPS6251370A - Scanner - Google Patents

Abstract

PURPOSE:To reduce the processing time by providing a designation information generating means outputting synchronizingly designation information on a binarization processing area and a pseudo half tone processing area on each side of a slip synchronously with the output of a binarization data and a pseudo half tone data from a processing means and a selection means for an external output so as to simplify the read processing operation. CONSTITUTION:The slip 12 is carried to the read position by a carrier roller 10 and a picture on the front and rear side of the slip 12 is read simultaneously by read sections 14A, 14B. The picture on the front and rear sides of the slip 12 is read at the same time in this way and the read information is transferred to an external picture processing system or the like in the order of the front side and the rear side. Thus, in inputting continuously plural slips to read each slip, the picture data of a continuous slip is inputted in the order of pages at the CPU side and it is not required for the processing such as the arrangement of pages. In designating properly the designation information onto designation tables 48A, 48B, an area for a photograph on each side of the slip 12 is read as a half tone picture and an area for a character or the like is read as a binary-coded picture.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a scanner that reads information on forms (not limited to sheet-like forms but also includes card-like forms; the same applies hereinafter). The present invention relates to a scanner that reads information on both sides of a form in one reading operation.

[Prior Art] Conventionally, a scanner used for an 0CR1 facsimile machine has a configuration including only one set of reading means consisting of a light source, an optical system, an image sensor, and the like.

[Problem to be solved] With this configuration, in order to read both sides of a form, first input the form into the scanner and read one side, then turn the form over, input it, and read the other side. It was necessary to perform the reading process twice, such as reading the side of the screen.

Such operations are not only troublesome, but also take a long time to read. In addition, even if there is a continuous paper feed function, if a large number of documents are input continuously using that function, only odd or even pages will be read continuously, and post-processing such as rearranging the read information in page order may result. is required.

[Purpose of the Invention] The purpose of this invention is to solve the above-mentioned conventional problems by making it possible to read both sides of a form at the same time, and to read an arbitrarily designated area of the form as a halftone image. The object of the present invention is to provide a scanner that can read the area as a binary image.

[Means for Solving the Problems] In order to achieve this object, the scanner according to the present invention includes two reading means for respectively reading the front and back sides of a form during the form conveyance path. A processing means configured to read both sides of a form by a reading operation of the reading means, further receiving image information read by the reading means and outputting binary data and pseudo halftone data of the image information. and designation information generating means for outputting designation information of the binarization processing area and the pseudo halftone processing area of each side of the form in synchronization with the output of the binarization data and pseudo halftone data from the processing means. and selecting means for selecting the binary data or pseudo halftone data outputted from the processing means bit by bit according to the specifying information to use as data for external output.

[Function] Since both sides of the form are read by just inputting the form once, the reading process operation for forms that require both sides to be read is simplified, and the reading process time is shortened.

In addition, when multiple forms are manually manually generated, it can be easily configured to output the read information on the front and back sides of each form to an external device in sequence, eliminating the need for conventional post-processing for page alignment. .

Furthermore, when recording a form as an image file on a medium such as an optical disk or transmitting the image data of the form, photographs and the like are recorded and transmitted as halftone images due to playback quality. From the viewpoint of data volume, it is desirable to record or transmit graphics as binary images. There are also forms that include a mixture of photographs and text.

The scanner according to the present invention can read a designated area on a form surface as a halftone image, and other areas as a binary image, so it can be used in systems such as those for converting and transmitting form images into files as described above. If the present invention is applied to an image input scanner, it can be applied to any form that is entirely a halftone image such as a photograph, a document that is entirely a binary image such as text, or a document that is a mixture of halftone and binary images. , it is possible to satisfy both the playback image quality and data amount.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows the main structure of a scanner according to the present invention.

In this figure, 10 is a conveyance roller for conveying the form 12 along the conveyance path.

A reading unit 14A for reading the front side of the form and a reading unit 14B for reading the back side of the form are provided in the middle of this conveyance path. Each read PIS14A, 1
4B has the same configuration, including a light source 18 (for example, a fluorescent light) for illuminating the reading position of the form, a one-dimensional image sensor 20 (for example, a COD linear image sensor),
It consists of a mirror 22, 24 and a lens 26 for forming an optical image of the reading position of the corresponding part of the form on the image sensor 20. The main scanning of reading is performed by the image sensor 20, and the sub-scanning is performed by feeding the form 12.

Here, the reading position of the back side reading unit 14B is a distance flil from the reading position of the front side reading unit 14A.
It is shifted by L in the transport direction 28.

If the reading position on each side is the same, the light source 18 of the back side reading section 14B can be used when handling thin or translucent forms.
There is an inconvenience in that the image on the back side is illuminated by the front side and is read by the front side reading section 14A, or similarly, the image on the front side is shown through on the back side and it is read by the back side reading section 14B. happen. However, as mentioned above, because the reading position of each commercial product's reading section is shifted in the transport direction, the image of the opposite side is not incident on each commercial product's reading section. The inconvenience will be resolved. Therefore, thin forms and translucent forms can also be processed. The deviation distance may be determined so that such a problem of transparency does not occur, and is determined to be, for example, about 30+m.

31 is a controller (CNTL) that is interfaced with the upper central processing unit (CPU). a control signal for a drive unit (not shown) of the conveyance roller 10;
Drive timing signals and the like for the image sensor 20 are output from this controller 31.

30A and 30B are image signal processing circuits that process analog image signals (image information) input from the image sensors 20 of the reading sections 14A and 14B, respectively, and convert the image information into binary data and pseudo halftone data. This outputs the following. The image signal processing circuits 30A and 30B have the same configuration, and include an analog/digital converter 32 that converts a human image signal into, for example, an 8-bit (64 gradation) digital image signal.
, a binarization circuit 34 that binarizes the digital image signal using a predetermined threshold value and outputs binarized data, and a dither processing circuit 36 that performs dither processing on the digital image signal and outputs pseudo halftone data. Line buffer 4 that temporarily stores data and pseudo halftone data for 1947 minutes each
Consists of 0.

The binarization circuit 34 is composed of a digital comparator, a ROM, etc., but may also be composed of an analog comparator that directly compares an analog image signal with a threshold value.

The dither processing circuit 36 may be constructed from a known ROM or the like, but may be replaced with a circuit that generates pseudo halftone data by a method other than the dither method. The line buffer y38 may be configured with a RAM or a shift register.

Clock for the analog/digital converter 32, element designation information of the dither matrix of the dither processing circuit 36,
Address information for line buffer 38 and 40
The read/write timing signal and the like are supplied from the controller 31.

44A and 44B are multiplexers, into which the binary data and pseudo halftone data output from the image signal processing circuits 30A and 30B are input.

Each multiplexer 44A, 44B has its control line 4
When 8A and 48B are "0", the input binary data is selected and sent to the output side as external output data, and when the control lines 48A and 46B are "L", the input pseudo halftone data is selected and sent to the output side as external output data. Select data as external output data and send it to the output side.

Reference numerals 48A and 48B are designation tables for generating designation information for binarization processing areas and pseudo halftone processing areas on the front and back sides of a form, and here they are constructed of RAM. Each bit of each designation table 48A, 48B is
It is associated with a unit area of 80×80 pixels (generally N×M pixels) on the form surface. Here, the reading section 14A.

Since the resolution of 14B is 16 lines/mm in both the main and sub-scanning directions, the unit area is a square area of 5×51a11.

Then, "1" is written in the bit corresponding to the unit area in the pseudo halftone processing area, and "0" is written in the bit corresponding to the unit area in the binarization processing area.

Writing of this designation information is performed by a higher-level central processing unit (CPU), not shown. At that time, write information is transmitted through signal lines 50A and 50B, and address information is transmitted through address lines 52A and 52B and multiplexers 54A and 54B.
It is supplied from the CPU through the CPU. FIG. 2 is a conceptual diagram showing a two-dimensional expansion of the designation table 48A or 48B.

The multiplexers 54A, 54B select one of the address lines 52A, 52B from the CPU or the address lines 58A, 56B from the controller 31 to output the designation table 48.
A, 48B, and the selection is made using the control line 58.
It is controlled by the controller 31 via A and 58B.

Line buffer 38 of image signal processing circuits 30A and 30B.
During the period when data is output from 40, multiplexer 5
4A and 54B are address lines 56A.

It can be switched to the 56B side. The controller 31 manages the scan addresses of pixels to which data is output from each line buffer 38, 40, and when the data of a certain pixel is output, designation information for the unit area on the form surface that includes that pixel is specified. Address information specifying the bit is placed on the address lines 58A and 56B, and the specified information is transferred to the control line 4O.
A, output to 48B. Therefore, for pseudo halftone processing areas on each side of the form, pseudo halftone data is selected by the multiplexers 44A and 44B, and for other binarization processing areas, binary data is selected. Become.

Reference numeral 60 denotes a page buffer capable of storing image data (binarized data or pseudo halftone data) for one page (one side) of a form, and is constituted by a RAM. Data input from the multiplexer 44B is written into this page buffer 60. This page buffer y60
A read/write address signal is supplied from the controller 31 via the address line 62.

The multiplexer 64 selects data output from the multiplexer 44A or the page buffer 60 and transfers it to the CPU via the transfer circuit 66, and the selection is controlled by the controller 31 via the control line 68.

Next, the overall operation of this scanner will be explained. In Figure 3,
The operation timing diagram is shown below.

The document 12 is conveyed to the reading position by the conveyance roller 10, and images on the front and back sides of the document 12 are simultaneously read by the reading sections 14A and 14B. Data corresponding to each side of the form 12 is output from the image signal processing circuit 30A 130B, and in synchronization with this, designation information is read from the designation tables 48A, 48B, and the multiplexer 44A is processed according to the designation information.

Data selection is made by 44B. First, the multiplexer 64 is controlled to select input data from the multiplexer 44A, and data corresponding to the front side of the form is transferred to the CPU via the transfer circuit 66. On the other hand, data corresponding to the back side of the form 12 is written to the page buffer 160.

When the rear end of the form 12 passes the reading position of the reading section 14B, the reading operation of the form 12 ends (the transport operation for ejecting the form, etc. is performed). After that, form 1
When the transfer of the data corresponding to the front side of 2 is completed, the multiplexer 64 is switched to the page memory 60 side, and the data corresponding to the back side is sequentially read from the page buffer 32 and transferred to the CPU via the transfer circuit 66.

In this way, the images of the front and back sides of the form 12 are read simultaneously, and the read information is sequentially transferred to an external image processing system or the like in the order of the front side and the back side. Therefore, when multiple forms are input in succession and each form is read, the image data of the successive forms will be input in page order on the CPU side, and it is necessary to perform processing such as page alignment. There is no.

By appropriately specifying specification information in the specification tables 48A and 48B, areas such as photographs on each side of the form 12 can be read as halftone images, and areas such as characters can be read as binary images. .

Note that if there is no problem with the processing ability of the side receiving and receiving the read data, it is also possible to adopt a configuration in which the read data from both sides of the form are transferred simultaneously or alternately and sequentially on a line-by-line basis.

The form conveyance mechanism is not limited to the roller conveyance mechanism as in the above embodiments, but may be a belt conveyance mechanism, for example.

The size of the unit area for area specification may be changed as appropriate.

The configuration of the reading section can also be changed as appropriate.

Furthermore, this invention is not limited to independent scanners;
It goes without saying that the present invention can be similarly applied to scanner units of R, facsimiles, electronic copying machines, image file systems, and the like.

[Effects of the Invention] As explained above, according to the present invention, it is possible to read both sides of a form just by manually reading it once.
The reading process for forms that require double-sided reading has become easier and the reading processing time has been shortened. Also, when multiple forms are input in succession, the reading information for the front and back sides of each form can be output externally in sequence. Because it is easy to configure, it eliminates the need for conventional post-processing for page alignment, and it also allows designated areas on the form to be read as halftone images, and other areas as binary images. Therefore, in systems that convert and transmit form images into files, it is possible to handle forms that are entirely halftone images such as photographs, forms that are entirely binary images such as text, and forms that are a mixture of halftone and binary images. In either case, form image information can be input so as to satisfy the conditions of both reproduction image quality and data amount. Effects such as this are achieved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a scanner according to the present invention, FIG. 2 is a conceptual diagram of a designation table, and FIG. 3 is an operation timing diagram of the scanner. 10... Conveyance roller, 12... Form, 14A...
Front side reading section, 14B...Back side reading section, 30A
. 30B... Image signal processing circuit, 31... Controller, 32... Analog/digital converter, 34... 2
Value conversion, circuit, 36... dither processing circuit, 38.4
0...Line buffer, 44A, 44B, 54A, 5
4B. 64... Multiplexer, 48A, 48B... Specification table, 60... Page buffer.

Claims (4)

[Claims] (1) Equipped with two reading means for respectively reading the front and back sides of the form during the form transport path;
It is configured to read both sides of a form in one reading operation, and further receives image information read by the reading means, and outputs binary data and pseudo halftone data of the image information. Processing means and specification information generation for outputting specification information of a binarization processing area and a pseudo halftone processing area of each side of a form in synchronization with the output of the binarization data and pseudo halftone data from the processing means. and selecting means for selecting the binary data or pseudo halftone data outputted from the processing means bit by bit according to the specified information and making it data for external output. (2) The processing means, the designated information generation means, and the selection means are respectively provided corresponding to the two reading means, and each operate independently. scanner. (3) The data for external output corresponding to one side of the form is temporarily stored, and the data for external output corresponding to the other side of the form is output to the outside, and then the data for external output is output to the outside. A scanner according to claim 1 or 2, characterized in that: (4) The designation information generating means includes a table in which each bit stores designation information for a corresponding unit area of N×M pixels on the form surface, and includes binary data and data corresponding to a certain pixel on the form surface. When the pseudo halftone data is output from the processing means, the designation information stored in the bit of the table corresponding to the unit area on the form surface including the pixel is output. A scanner according to any one of claims 1 to 3.