JP2632709B2 - Automatic facsimile mode selection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Summary] In a facsimile apparatus, a normal G3 communication mode,
A facsimile mode automatic selection device that switches between the G3 error correction mode according to the nature of the image and a facsimile mode automatic selection device that can set the communication mode to the error correction mode only when necessary. In a facsimile apparatus having a normal G3 communication mode and a G3 error correction mode, an image storage device for temporarily storing read image data, and an image data stored in the image storage device And a mode switching device for switching between the normal G3 communication mode and the G3 error correction mode according to the number of change points of the image data obtained by the change point data calculation device. It is comprised so that it may have.

[Industrial applications]

In the facsimile machine, the normal G3 communication mode,
The present invention relates to a facsimile mode automatic selection device that switches between a G3 error correction mode and an image property.

[Conventional technology]

Conventional facsimile machines usually use ISO A4
Communication is performed by the G3 communication mode, which transmits a document of a size in about one minute. Recently, G3 error correction mode, which uses a new method of erafree, has been used to improve transmission quality. In this method, the conventional G3 communication mode was set to check whether the data was sent correctly for each unit (hereinafter referred to as a block) divided into a certain amount of data, whereas the conventional G3 communication mode sent data in a no-check flow. It was done. In other words, the end of the block is notified from the transmitting side by a low-speed signal of 300 bps in the form of interrupting the high-speed signal of the image data, and the receiving side also notifies the receiving side of whether or not the block was correctly received by the low-speed signal. As a result, the communication is performed while being checked.

[Problems to be solved by the invention]

By the way, in such conventional facsimile transmission in the G3 error correction mode, a check is performed each time a block is completed, so that a time loss occurs during this time. Further, when the line condition is poor, the block is retransmitted. However, it takes a long time, and the transmission time is further increased. And this kind of time loss can be offset by the great merit of sending high quality screens when sending detailed screens, even if it takes much time, but I want to send time loss The same occurs when the screen is fine or not, so even if there are some errors on the screen, such as when sending large characters, etc., if the screen can be decoded, retransmission etc. The time spent for this purpose is wasted.

The present invention has been made in view of such a conventional problem. According to the nature of a screen, a facsimile mode automatic selection device capable of setting a communication mode to an error correction mode only when necessary is provided. Its purpose is to gain.

[Means for solving the problem]

Means for solving the above problems in the present invention include:
As shown in FIG. 1, in a facsimile apparatus 1 having a normal G3 communication mode 2 and a G3 error correction mode 3, an image storage device 6 for temporarily storing image data 5 read by a facsimile transmission device 4 And a change point data calculation device 7 for calculating the number of change points of the image data stored in the image storage device 6; and the number of change points of the image data calculated by the change point data calculation device 7.
A mode switching device 8 that switches between G3 communication mode 2 and G3 error correction mode 3 is provided.

[Action]

Next, the operation of the present invention will be described with reference to FIG. 1. An image storage device 6 temporarily stores the read image data 5, and a change point data calculation device 7
The number of change points of the image data stored in the forgery storage device 6 is obtained. The mode switching device 8 switches between the normal G3 communication mode 2 and the G3 error correction mode 3 on the basis of the number of change points of the image data obtained by the change point data calculation device 7 to determine the number of change points. Only when there is a lot of data, communication is performed by the G3 error correction mode.

〔Example〕

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 2 is a block diagram showing one embodiment of the present invention. In this case, the facsimile apparatus 1 is configured such that both the transmitting apparatus and the receiving apparatus operate in both the normal G3 communication mode and the G3 error correction mode. It is assumed that communication is performed in the mode.

The transmission device 4 of the facsimile apparatus 1 includes a main control unit 11, the main control unit 11 includes a data reading unit 12 that reads an image from a sheet for transmission, and an image storage device that temporarily stores read image data. 6. An image data processing unit 13 for performing image compression and the like on the read data is attached. In addition, the main control unit 11 includes a change point data calculation device 7 for calculating the number of change points of the image data 5 stored in the image storage device 6.
The transmission control unit 14 connected to the main control unit 11 has the normal G3 communication mode 2 based on the number of change points of the image data obtained by the change point data calculation device 7.
And a mode switching device 8 for switching between G3 and G3 error correction mode 3.

The image storage device 6, the change point data calculation device 7, and the mode switching device 8 form an automatic facsimile mode selection device 10. Also, from the transmission control unit 14,
Data is transmitted via the modem 15 and the NCU 16. The main control unit 11 also has a built-in control device for receiving, and is further connected to a recording unit 17.

FIG. 3 is a flow chart of the operation of the device of the present invention. The image storage device 6 temporarily stores the read image data 5 (S1), and from the storage content of the image storage device 6,
The change point data calculation device 7 obtains data on the number of change points in the image data (S2). Next, the main controller 11 compares whether or not the change point data is larger than a specified value (S3). If it is larger than the specified value, a flag of an error correction mode (hereinafter referred to as ECM) is turned on (S3).
4) Otherwise, turn off the ECM flag (S
Five). Next, it checks whether the ECM flag is on or off (S6). If the flag is on, communication is performed in the G3 error correction mode 3 (S7). If the flag is off, communication is performed in the normal G3 communication mode 2 (S8). .

These operations are performed by the mode switching device 8 in the transmission control unit 14. If the number of change points in the stored image is large, that is, if the image is a fine image and any error occurs, even if a slight error occurs. When transmitting a screen in which the image quality is deteriorated due to the screen being disturbed, the communication mode is switched to the G3 error correction mode 3 so that the image quality does not deteriorate. When transmitting a large character or the like having a small number of change points, transmission is performed in the normal G3 communication mode 2 to minimize time loss.

〔The invention's effect〕

As described above, according to the present invention, in a facsimile apparatus having a G3 communication mode and a G3 error correction mode, the image to be transmitted is a fine image, and if an error occurs, the screen is disturbed, and the image quality is reduced. G3 only when there is a risk of sending a screen
By switching to the error correction mode and sending, the facsimile image quality is improved for fine images, and decoding is possible even if there is some error on the screen, such as when sending large characters etc. As far as possible, transmission is performed in the G3 communication mode, so that time is not wasted. In this way, it is possible to obtain a facsimile apparatus with good image quality and high transmission speed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the principle of the present invention, FIG. 2 is a block diagram of an apparatus according to an embodiment of the present invention, and FIG. 3 is a flowchart showing the operation of the apparatus shown in FIG. DESCRIPTION OF SYMBOLS 1 ... Facsimile apparatus 2 ... G3 communication mode 3 ... G3 error correction mode 5 ... Image data 6 ... Image storage apparatus 7 ... Change point data calculation apparatus 8 ... Mode switching apparatus 10 ... Mode automatic selection apparatus

Claims (1)

(57) [Claims] An image storage device (6) for temporarily storing read image data (5) in a facsimile device (1) having a G3 communication mode (2) and a G3 error correction mode (3). A change point data calculation device (7) for calculating the number of change points of the image data stored in the image storage device (6); and a number of change points of the image data calculated by the change point data calculation device (7). G3 communication mode (2) and G3
A mode switching device (8) for switching between an error correction mode (3) and a mode automatic selection device for a facsimile.