JPH01134574A - Image input device - Google Patents

Abstract

PURPOSE:To realize an image information filing system with use of a host computer having high versatility by adding a bidirectional interface for transfer of image information, a coding circuit and a decoding circuit to an image input device. CONSTITUTION:When a read control command is received from a host computer, a reading part 13 reads an original in accordance with the command and stores the reading result in a line buffer 14. A coding/decoding control part 16 codes the image data stored in the buffer 14 to send this decoded data to an image memory 15 and sends a transfer end signal to a main processing part 10. The part 10 transfers the image data on the memory 15 to the host computer via a bidirectional interface 12. While the image data filed in the host computer is decoded by the part 16 and returned to the host computer to be sent to an output device for application.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to an image input device such as an image scanner connected to a host computer such as a personal computer or a word processor.

(b) Conventional technology As disclosed in Japanese Patent Application Laid-Open No. 12273/1983, a general image input device reads an image on a document with an image sensor and digitizes it using a DA converter or the like. The configuration was simply to send value or multi-value image data to a host computer.

Furthermore, in recent years, devices such as facsimile devices that encode read image data within an image input device and send this encoded data to a host computer have become available.

(8) Problems to be Solved by the Invention In the prior art, when the configuration is such that read binary or multivalued image data is simply sent out, a device with a large capacity is used as a file device for storing image data on the host side. There were problems in that an encoding circuit had to be provided in order to send the data from the host to the outside. In addition, in a configuration in which data is encoded within the image input device, the data is compressed, so the capacity of the file device is small, but the encoded data cannot be used as is on the host side, so it must be decoded to the original image data. The host computer must be equipped with a decoding circuit for
, it was unsuitable for a general-purpose host computer such as a personal computer.

(d) Means for Solving the Problems The present invention provides an image input device that is connected to a host computer, has a reading unit that reads an image on an object to be read, and inputs image information of the read image to the host computer. , an encoding circuit for encoding image data, a decoding circuit for decoding encoded data, and for exchanging the image data, encoded data, and decoded data as image information with the host computer. A two-way interface is provided to solve the above problems.

(*) Effect In the present invention, since the image input device is provided with a bidirectional interface, an encoding circuit, and a decoding circuit for image information transfer, image data or encoded data can be transferred from the host side to the image input device, Encoding and decoding processing can now be executed within the device. Therefore, when using image data on the host side, the image data is transferred as is from the image input device, and when filing or transferring it externally,
Sends image data from the host to the image input device, encodes it, returns the encoded data to the host, and then sends the encoded data to the image input device when using encoded data that has already been filed. However, by decoding the data within the device and returning the decoded data to the host, an image information filing system can be realized.

(F) Embodiment FIG. 1 is a block diagram showing an embodiment of an image input device according to the present invention, and FIG. 2 is a system block diagram showing an image information filing system using the image input device shown in FIG.

First, in FIG. 2, (1) is a general-purpose host computer such as a personal computer that does not have encoding and decoding means, (2) is a communication interface for performing data communication between the host and external equipment, (3) is a display device for displaying image data, (4) is a printing device for printing image data, and (5) is an external storage device as a file device for filing encoded data as image information. , (6) is an image input device that inputs image information on the document (7) to the host computer (1).

As shown in FIG. 1, the image input device (6) has a system data bus (8a), a system address bus (8b),
System bus (8) consisting of system control bus (8c)
, image data bus (9a), image address bus (9b)
), an image bus (9) consisting of an image control bus (9c), and a system bus (8).
On the side, there is a main processing unit (MPU) (10), a system memory (11) consisting of a ROM area that stores one program and a RAM area that temporarily stores various data.
A parallel two-way interface (12) for exchanging image information and control commands with the host computer 4 (1) is connected.

Furthermore, in FIG. 1, (13) is a light source for illuminating the original;
It consists of a COD image sensor, an AD converter, a motor, a line buffer, a control unit, etc. It reads the image on the document and stores the binary or multivalued image data in the line buffer (1
4), and then supply the image bus (9) to the reading unit (1
5) is an image memory that stores image data, and (16) executes encoding and decoding processing according to commands from the main processing unit (10), and also uses an image bus (9) for the image memory. It is an encoding/decoding control unit that controls writing and reading of data, and it is designed so that the image memory (15) can be accessed not only from the image bus (9) side but also from the system bus (8) side. ) and both buses, a switching gate (17) is inserted between the main processing section (10)
Switching control is performed at , so that either one of the buses can be connected to the image memory (15). Further, as the encoding/decoding control unit (16), for example, IC'DI manufactured by Hitachi
CEP (HD63085) J may be used, and as shown in FIG. 3, it contains an image bus interface (20) including an encoding circuit (18), a decoding circuit (19), an image bus controller, and a DMA controller; It has a system bus interface (21) including a system bus controller and a microprogram control section (22).

Next, the functions of the image input device will be described in detail.

This image input device (6) roughly has a first function of reading a document image and transmitting the read image data to the host in response to a control command from the host computer (1), and a first function of reading the document image. , a second function that encodes the read image data and transfers the encoded data to the host; a third function that decodes the encoded data from the host and transfers the decoded data to the host; and a third function that encodes the image data from the host. It has four functions, the fourth function is to encode data and transfer the encoded data to the host.

That is, the control command ST is sent from the host computer (1).
When input, the main processing unit (10) controls the switching gate (17) to transfer the image memory (15) to the image bus (9).
) to give a one-line reading command to the reading section (13) and a DMA command to the encoding/decoding control section (16). The reading unit (13) scans the original according to the command, reads one line, stores the read image data in the line buffer (14), and encodes and decodes the one line reading process end signal after storing. It is sent to the control section (16). The encoding/decoding control unit (16) stores the image memory (1) in response to the end signal.
5) into memory write state, line buffer (14)
The image data is transferred to the image memory (15) by DMA. When the DMA transfer is completed, the encoding/decoding control unit (16)
The main processing unit (10) uses an interrupt to indicate the end of DMA.
In response to this interrupt, the main processing unit (10) switches the switching game (17) to the system bus (8) side, puts the image memory (15) in the memory read state,
The image memory (
Transfer the image data of 15) to the host computer (1). These series of processes are repeated until the processes for all lines in the designated reading range are completed.

Also, when the control command CM is input from the host computer (1), the reading section (13) is activated and the image data is stored in the image memory (15), as in the case of the control command ST.
), but when the main processing section (10) receives an interrupt indicating the end of DMA, the switching gate (17) is not switched and an encoding command is given to the encoding/decoding control section (16). In response to this command, the encoding/decoding control unit (16) puts the image memory (15) into a memory read state, reads out the image data, executes encoding processing, and sequentially sends the encoded data to the system bus. The main processing unit (10) sequentially takes in the encoded data on the system bus and sends it to the host computer (1) via the bidirectional interface (12).
Transfer encoded data to. Encoding/decoding control unit (16
) When the encoding process for one line is completed, the main processing unit (10) is notified of this by an interrupt, so the main processing unit (10) responds to this interrupt and completes the processing of all lines in the specified reading range. It is determined whether or not the processing has been completed, and if the processing has not been completed, a similar command is issued for processing the next line.

On the other hand, when the control command EX is input and encoded data is subsequently input via the bidirectional interface (12), the reading unit (13) is not activated and the main processing unit (10) is activated by the switching gate (17). ) is switched to the image bus (9) side, the system memory (11) is put into a memory write state, and encoded data input to the RAM area is stored. Next, a decoding command is given to the encoding/decoding control unit (16), and input encoded data is read from the RAM area of the system memory (11), and the encoding/decoding control unit (
16). In the encoding/decoding control unit (16),
The encoded data input in accordance with the command is decoded, and the encoded data is written into the image memory (15) with the image memory (15) in a memory write state. When the writing is completed, the encoding/decoding control unit (16) sends the main processing unit (10
), and in response to this interrupt, the main processing unit (10) switches the switching game (17) to the system bus (8) side. Then, the image memory (15) is brought into a memory read state, and the encoded data is read out and transferred to the host computer (1) via the bidirectional interface (12).

Furthermore, when the control command RC is input and image data is subsequently input via the bidirectional interface (12), the reading unit (13) is not activated and the main processing unit (10) is activated by the switching gate (17). Switch to the system bus (8) side, set the image memory (15) to the memory write state,
Next, the input image data is written into the image memory (15), the switching gate (17) is switched to the image bus (9) side, and an encoding command is given to the encoding/decoding control section (16). The encoding/decoding control unit (16) puts the image memory (15) in a memory read state according to the command, reads out the image data, executes the encoding process sequentially, and sends the encoded data onto the system bus (8). do. The main processing unit (10) transfers this encoded data to the host computer (1) via the bidirectional interface (12).

Therefore, in the filing system shown in FIG. 2, when the host computer (1) wants to obtain image data of an image on a document, it sends a control command ST to the image input device (
6), and if you want to file or send it to the outside after editing and checking the obtained image data using the display device (3) and printing device (4), edit and check the image data. Control command RC for image data after confirmation
It would be better to send it along with it. Then, the encoded data transferred from the image input device (6) may be stored in the external storage device (5) or transferred to the outside via the communication interface (2). Also, if you want to use encoded data that has been filed in this way or transferred from the outside, you can send the encoded data to the image input device (1) along with the control command EX.
The decrypted data is returned to the host computer (1). Furthermore, by sending the control command CM, it is also possible to directly obtain the encoded data of the read image.

Note that in the image input device, the system bus and the image bus do not necessarily have to be separated.

(g) Effects of the Invention According to the present invention, image information of a read image can not only be simply inputted to the host combicoater, but also can be inputted without any encoding and decoding means in the host combicoater. Since the processing can be realized, it becomes possible to configure an image information filing system using a highly versatile host computer such as a personal computer. Of course,
Since encoded data can be used as filing data, there is no need to use a file device with a large capacity.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, and FIG.
The figure is a system block diagram showing an image information filing system using the embodiment, and FIG. 3 is a block diagram showing the specific configuration of the encoding/decoding control section in the embodiment. (1)...Host computer, (3)...Display device, (5)...External storage device, (6)...Image input device, (8)...System bus, (9) ...Image bus, (10)...Main processing unit, (12)...Bidirectional interface, (13)...Reading unit, (1
5)...Image memory, (16)...Encoding/decoding control unit, (17)...Switching gate, (18)...
Encoding circuit, (19)...Decoding circuit.

Claims (1)

[Claims] (1) In an image input device that is connected to a host computer and has a reading unit that reads an image on an object to be read, and inputs image information of the read image to the host computer, an encoding circuit that encodes image data; , comprising a decoding circuit that decodes encoded data, and a bidirectional interface that exchanges the image data, encoded data, and decoded data as image information with the host computer. image input device.