JPH084309B2 - Image transmission method - Google Patents

Description

The present invention relates to an image transmission method, and more particularly to an image transmission method suitable for transmitting / receiving digital image data via a communication line or the like.

[Conventional technology]

As a method of transmitting and receiving digital pixel data via a communication line or the like, a compression encoding method is adopted in order to efficiently transmit a large amount of binary image data. For example, in facsimile, MH (Modified Huffman)
The compression or MR (Modified READ) compression method is standardized.

Even in an image data storage device called a so-called document file device, it is possible to compress and convert a large amount of digital image data using a compression encoding method such as MH compression and MR compression, and store it, for example, in "Nikkei Electronics" 1983. Three
No. 28, p. 113 to 114, etc. When the stored image is used for the image data storage device from a remote image station device located at another distant place, the image data in the compressed and stored form is transmitted via a serial data line such as a communication line. Then, after the image data is expanded on the remote image station device side and converted into dot data, it is displayed on a display device or printed out on a printing device for use.

[Problems to be solved by the invention]

In the above-mentioned conventional technique, the linear density when the image data storage device stores the image data depends on the input device such as a scanner that inputs the image by the conversion from analog to digital. Then, the higher the linear density, the closer the reproducibility becomes to the original image, and the higher degree of utilization is possible, but the amount of image data also increases. Therefore,
When the image data having such a property is transmitted through a communication line or the like and is to be displayed or printed, if the line density of the stored image data is large and the communication line speed is low, the transmission time is increased. There is a problem of cost.

On the other hand, the linear density of the output device on the remote image station device side does not always match the linear density of the stored image data to be used. Normally, the linear density of a display device such as a display is lower than that of an input device such as a scanner or an input device such as a printer. When the scanner or printer has 8 dots / mm or 16 dots / mm, the display device has Only dots / mm can be displayed. Therefore, in order to display the image on the display device, the received image is used after being subjected to linear density conversion. Moreover, when searching for an image that the user needs while viewing the displayed image, the response time of the images displayed one after another becomes a problem.

An object of the present invention is to provide an image transmission method in which the response speed to the user is improved according to the purpose of using the image data of the user on the remote image station device side, for example, display or printing.

[Means for solving problems]

The above-mentioned object is to automatically transmit the image data stored in the image data storage device to the remote image station device while automatically converting it into a linear density suitable for the usage pattern of the remote image station device. Achieved by

[Action]

In the image transmission method of the present invention, for example, the image data stored in the image data storage device is 16 dots / mm, and the linear density of the display device on the remote image station side is 4 dots.
In the case of / mm, the amount of image data to be transmitted is reduced to 1/8. Therefore, the transmission time of image data is also reduced to 1/8. As a result, it is possible to shorten the transmission time without changing the quality of the image displayed by converting it according to the line density of the display device at the remote station after transmitting it with the accumulated line density. The response speed to the user can be improved.

〔Example〕

 An embodiment of the present invention will be described below with reference to the drawings.

In the figure, the image filing apparatus 1 is connected to a remote image station apparatus 2 via a communication line 3. The image filing device 1 includes an operation unit A11 operated by an operator, an image input unit 12 for setting an input image, an image memory 13 for storing input image data, an image compression unit 14 for compressing image data, A compressed image storage / storage unit 17 that stores this compressed image data and a control unit A10 that controls each unit.
It has. Further, the control unit A10 includes an image read / write control unit 15 for controlling read / write of the compressed image storage / storage unit 17, an image linear density conversion unit 18 for converting the linear density of an image, and a remote image station device 2. It controls the communication transmission control unit A21 that performs the data transmission of. The output of the image compression unit 14 is connected to the temporary memory 16 for temporarily storing, and the output of the image linear density conversion unit 18 is connected to the response image transmission buffer 20 which is a data buffer. And
Converted linear density designated area 1 for smooth image transmission
9, request reception buffer area 22, station No area 2
3. A request image ID area 24 and a designated linear density area 25 are provided.

On the other hand, the remote image station device 2 includes an operation unit B51 operated by an operator, a communication transmission control unit B56 for performing data transmission between the image filing device 1, and image data from the communication transmission control unit B56. A response image receiving buffer 57 for temporarily storing the image data, an image decompression unit 58 for decompressing the compressed image data, an output selector 59 for selecting an output device of the display device 62 or the printing device 63, and these components. Consists of control unit B50. The select lines of the output selector 59 are connected to the display dot memory 60 and the print dot memory 61 respectively, and
The image data in 60 is sent to the display device 62, and the image data in the printing dot memory 61 is sent to the printing device 63. Further, a request transmission buffer area 52 is provided to smoothly perform image transmission. The details of this area are the same as those on the image filing device 1 side.

 Next, the operation will be described.

In the image filing device 1, the user sets an input image in the image input unit 12 and gives an image input instruction from the operation unit A11. When the control unit A10 receives an image input instruction via the operation unit A11, the control unit A10 gives an input start instruction to the image input unit 12 and loads dot data into the image memory 13. afterwards,
The control unit A10 issues an image compression instruction to the image compression unit 14. The image compression unit 14 performs data compression processing,
The dot data of the input image in the image memory 13 is output to the temporary memory 16 as compressed image data, and the control unit A10
To the compression completion report. Upon receiving the compression completion report, the control unit A10 issues a write instruction of the compressed image data in the temporary memory 16 to the image read / write control unit 15, whereby the image read / write control unit 15 is instructed. The compressed image data in the temporary memory 16 is stored in the compressed image storage storage unit 17. When storing the compressed image data, the image I input by the user from the operation unit A11 in advance is stored.
Stored by linking with D and image attribute (line density and size) information.

When the compressed image data stored in the compressed image storage unit 17 of the image filing device 1 is used for display on the remote image station device 2 side connected via the communication line 3, first, the image filing device 1 side In order to accept the request 4 from the remote image station apparatus 2, the user gives a service permission instruction to the remote image station apparatus 2 for the image data from the operation unit A11. Control unit A10 that received the service permission instruction
Issues a reception instruction by giving the address of the request reception buffer area 22 to the communication transmission control unit A21, waits for a reception completion report from the communication transmission control unit A21, and waits.
Then, the user selects the image ID of the image to be viewed from the operation unit B51 of the remote image station device 2 and gives a display instruction. The control unit B50 switches the output selector 59 to the display dot memory 60 side based on the display instruction received via the operation unit B51. Further, the linear density data of the display device 62, the designated image ID, and its own station No. are respectively assigned to the designated linear density area 5 in the request transmission buffer area 52.
5, set in the requested image ID area 54 and the station No area 53, and stored as transmission data for the image filing apparatus 1.

Next, the control unit B50 gives the communication transmission control unit B56 the address and size of the request transmission buffer 52 and issues a transmission instruction. After the transmission is completed, the address of the response image reception buffer 57 is given to the communication transmission control unit B56, a reception instruction is issued, and the communication transmission control unit B56 waits for a reception completion report and waits.

The request 4 transmitted from the communication transmission control unit B56 via the communication line according to the transmission instruction of the control unit B50 of the remote image station apparatus 2 is received by the communication transmission control unit A21 of the image filing apparatus 1. The communication transmission control unit A21 stores the request data in the request reception buffer area 22. When storing, the station number data is stored in the station number area 23 and the designated image ID data is stored in the requested image ID area 24.
Further, the linear density data of the display device 62 is stored in the designated linear density area 25, respectively. The communication transmission control unit A21 waits for a reception completion report when the storage of the request data in the request reception buffer 22 is completed, and with respect to the control unit A10 that has been waiting,
Report reception completion. Upon receiving the reception completion report, the control unit A10 issues an instruction to read the image data of the image ID stored in the requested image ID area 24 in the requested reception buffer area 22,
Issued to the image read / write control unit 15. Upon receiving the read instruction, the image read / write control unit 15 reads the image data and the image attribute (linear density and size) information corresponding to the designated image ID from the compressed image storage storage unit 17 into the temporary memory 16. After the reading is completed, the control unit A10 is notified of the completion of reading. Control unit A10 that received the read completion information
Is the linear density of the image attribute read in the temporary memory 16 and the designated linear density area 25 in the request reception buffer area 22.
The required linear density data stored in is compared. If the required linear density is smaller, the required linear density is set in the converted linear density designation area 19. If equal or greater,
The linear density data read into the temporary memory 16 is set in the conversion linear density designation area 19. And the control unit A10
Issues a linear density conversion instruction to the image linear density conversion unit 18. Image linear density conversion unit 18 which has received the linear density conversion instruction
Converts the linear density of the compressed image data read in the temporary memory 16 based on the linear density data of the converted linear density designation area 19, and outputs the converted compressed image data to the response image transmission buffer 20. . Here, as described above, when the required linear density is smaller than the linear density of the image attribute read in the temporary memory 16, the required linear density is set in the conversion linear density designation area 19, The compressed image data read in the temporary memory 16 is converted into compressed image data having a required linear density and output to the response image transmission buffer 20. On the contrary, if the required linear density is greater than or equal to the linear density of the image attribute read in the temporary memory 16, as described above, the temporary memory 16
The line density of the image attribute read in is converted and the line density specification area
Since it is set to 19, the compressed image data read in the temporary memory 16 is not subjected to the linear density conversion substantially, and the response image transmission buffer 20 has the linear density as it is.
Is output to When the above process is completed, the image linear density conversion unit 18 reports the completion of conversion to the control unit A10. When the conversion end is received, the control unit A10 sends the communication transmission control unit A21 a station No area in the request reception buffer 22.
The partner station No. 23 and the address and size of the compressed image data in the response image transmission buffer 20 are given and a transmission instruction is issued. After the transmission is completed, the control unit A10 again gives the communication transmission control unit A21 the address of the request reception buffer area 22 and issues a reception instruction, and waits for a reception completion report, and the image filing device 1 receives the next request. I will be waiting.

The response 5 transmitted from the communication transmission control unit A21 via the communication line 3 according to the transmission instruction of the control unit A10 of the image filing device 1 is received by the communication transmission control unit B56 of the remote image station device 2. The communication transmission control unit B56 stores the response data in the response image reception buffer 57, and waits for the reception completion report, and reports the reception completion to the waiting control unit B50. Upon receiving the reception completion report, the control unit B50 gives the image decompression unit 58 the address and size of the compressed image data in the response image reception buffer 57 to instruct the image decompression. The image decompression unit 58 decompresses the compressed image data in the response image reception buffer according to the image decompression instruction, and transfers the dot data to the display dot memory 60 through the output selector 59 set in advance by the control unit B50. When the expansion / transfer of the compressed image data in the response image reception buffer 57 is completed, the image expansion unit 58 completes the control unit B5.
Report decompression completion to 0. Upon receiving the decompression completion report, the control unit B50 issues a display request to the display device 62. Display device 62
Receives the display request, displays the image data stored in the display dot memory 60. And the control unit B50
Is waiting for the next operation.

Similarly, when outputting to the printing device 63 on the remote image station device 2 side, the output selector 59 switches to the dot memory 61 for printing, and the linear density data of the printing device 63 is set to the specified linear density in the request transmission buffer area 52. It is realized by storing it in the area 55 as transmission data and transmitting it to the image filing apparatus 1 side.

〔The invention's effect〕

According to the present invention, the transmission time can be shortened as the linear density of the image data stored in the image filing device is larger than the linear density of the output device of the remote image station device using the image data. Therefore, there is an effect of improving the response speed to the user. Therefore, when the image filing device is accessed and searched, there is an effect that it can be efficiently performed.

Further, according to the present invention, the effect that the digital image data can be transmitted at high speed to the remote image station apparatus by the output means of the image selected by the user on the side of the remote image station apparatus, for example, the linear density according to the display or the printing. There is.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a schematic configuration of an image filing device and a remote image station device to which an image transmission system according to an embodiment of the present invention is applied. DESCRIPTION OF SYMBOLS 1 ... Image filing device, 2 ... Remote image station device, 3 ... Communication line, 4 ... Request signal, 5 ... Response signal, 10 ... Control part A, 15 ... Image read / write control part, 17
... compressed image storage / storage section, image linear density conversion section, 21 ... communication transmission control section A, 50 ... control section B, 56 ... communication transmission control section B, 58
... image expansion unit, 59 ... output selector, 60 ... display dot memory, 61 ... application dot memory, 62 ... display device, 63 ... printing device.

Claims (1)

[Claims] 1. An image transmission method for reading digital image data from an image filing device and transmitting the read digital image data to a remote image station device via a communication line, wherein the remote image station device is instructed by a user. Accordingly, one output means is selected from a plurality of image output means provided in the remote image station apparatus, and the information of the linear density corresponding to the selected output means is transmitted to the image filing apparatus. The second step of comparing the linear density information of the digital image data accumulated in the image filing apparatus with the transmitted linear density information of the output means, As a result of the comparison in the step, If it is determined to be smaller than the linear density of the digital image data product,
The image filing device converts the linear density of the digital image data output to the communication line into the linear density of the output means and outputs the linear density of the selected output means as a result of the comparison in the third step and the second step. When it is determined that the density is equal to or higher than the linear density of the digital image data stored in the image filing device, the image filing device outputs the stored digital image data to the communication line with the linear density as it is. An image transmission method comprising the following steps: