JPS6251028B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for compressing and transmitting information including images and characters.

[Conventional technology]

In conventional facsimile and other image transmissions, even if the screen to be transmitted consists only of characters, the entire screen is scanned and transmitted.
When image information obtained by scanning the entire screen is subjected to band compression in this manner, the band compression rate is on average about 1/7 to 1/10. On the other hand, when reading character information with an optical character reader (OCR) and encoding it, for example, a 5 mm x 5
Since the 800-bit pixels of a mm character can be compressed into an 8-bit code, a good compression ratio of about 1/100 can be obtained.

Therefore, a method has been proposed in which image information and character information are distinguished, and the image information is transmitted after normal band compression, and the character information is converted into a character code and transmitted (Japanese Patent Laid-Open No. 52-113119). Public bulletin).

[Problem that the invention seeks to solve]

However, a document may include characters such as handwritten characters that cannot be converted into character codes, and there have been cases where character information cannot be converted into character codes and transmitted.

SUMMARY OF THE INVENTION An object of the present invention is to provide a system that can increase the information compression rate of image signals on average and transmit unreadable characters as image information.

[Means for solving problems]

The present invention provides an image transmission means for band compression encoding and transmitting information obtained by scanning a screen as image information, and an image transmission means that scans the screen in rows and columns and reads and identifies characters, and converts the obtained information into character information. A character transmission means for encoding and transmitting characters, and a mode switching means for selecting between these two means by mode switching,
When transmitting information by selecting a character mode, if characters cannot be read and identified, the mode is automatically switched to image mode and the characters that cannot be read and identified are rescanned. It is characterized by encoding and transmitting information.

〔Example〕

This will be explained with reference to the drawings.

The figure is a circuit configuration diagram of a device according to an embodiment of the present invention. In the figure, the output of a screen scanning device 1 is given to a mode switching circuit 3 via a screen scanning control circuit 2. The output of the mode switching circuit 3 is the band compression circuit 4.
Alternatively, it is switched and applied to the character reading circuit 5. The output of the character reading circuit 5 is given to a character code generation memory 6, and the output of this character code generation memory 6 and the output of the band compression circuit 4 are combined by a transmission buffer control circuit 8 and supplied to a transmission buffer 9. . The output of this transmission buffer 9 is
The signal is provided to the line correspondence section 11 via the transmission control circuit 10 and is configured to be sent out to the line 12.

In the device configured in this way, the screen to be transmitted is supplied to the screen scanning device 1, and is optically scanned under the control of the screen scanning control circuit 2. The pixels thus obtained are transferred to the band compression circuit 4 or the character reading circuit 5 according to the designation of the mode switching circuit 3.

Now, when the mode of the mode switching circuit 3 is set to the image mode designation, the scanning control circuit 2 is controlled by the band compression circuit 4, and the image signal obtained as an output is processed by the band compression circuit 4 using, for example, a Huffman code. and is expanded into compressed code. This compressed code is stored in the transmission buffer 9 under the control of the transmission buffer control circuit 8. Its contents are
The data is read out by a transmission control circuit under the control of the band compression circuit 4, configured into a transmission frame, and sent from the line correspondence section 11 to the line 12.

Further, when the mode of the mode switching circuit 3 is set to character mode designation, the scanning control circuit 2 is controlled by the character reading circuit 5, and the screen is scanned in units of rows and columns. The output of the scanning control circuit 2 is transferred to the character reading circuit 5. The character reading circuit 5 identifies the character from the transferred pixels, generates a code for the corresponding character from the character code generation memory 6, and stores it in the transmission buffer 9 via the transmission buffer control circuit 8. The contents are read by a transmission control circuit 10 controlled by a character reading circuit 5 and sent from a line correspondence section 11 to a line 12.

Furthermore, the specified mode of the mode switching circuit 3 is given to the transmission control circuit 10, which generates a mode setting signal to transfer the signal from the line corresponding section 11 to the line 12.
It is used to select the mode of a corresponding receiving device (not shown).

Here, the character mode is designated when only characters consisting of numbers and alphabets (and kana) are written on the screen supplied to the screen scanning device. When the character reading circuit 5 is constructed at low cost and its functions are limited, it is necessary that the characters are correctly written in the matrix according to a certain standard. When the function of the character reading circuit 5 is large, restrictions on the size and other forms of written characters are relaxed. In this example, the characters are basically only alphanumeric characters and numbers expressed in a 5 x 5 (mm) square.
The one that expands to JIS7 (or JIS8) code was adopted.

Here, the characteristic operation of the present invention will be explained.

The transferred pixels are analyzed by the character reading circuit 5, and when the character cannot be identified with the ability of the character reading circuit 5, the fact that the character cannot be identified is sent back to the mode switching circuit 3. Thereby, the mode switching circuit 3 automatically converts the mode designation to the image mode. Furthermore, by controlling the scan control circuit 2,
The portion of the characters that could not be identified is scanned again and transmitted as image information. When the transmission of that character is completed, the mode designation is automatically changed to character mode again, and the next character is read.

In this way, information for which the image mode is automatically and temporarily specified is printed as a blank at the corresponding character position on the receiving device, and is also reproduced and recorded as an image on the margin of the screen or on another screen. Ru. According to this method, the present invention can be implemented even when the characters on the original screen are uncertain characters such as handwritten characters.

〔Effect of the invention〕

As described above, according to the present invention, there is an effect that even handwritten characters that cannot be read can be automatically transmitted as image information.

[Brief explanation of the drawing]

The figure is a configuration diagram of a transmitting device according to an embodiment of the present invention. 1... Screen scanning device, 2... Screen scanning control circuit, 3
...Mode switching circuit, 4...Band compression circuit, 5...Character reading circuit, 6...Character code generation memory, 8...Transmission buffer circuit, 9...Transmission buffer, 10...Transmission control circuit, 11...Line correspondence section, 12...Line .

Claims (1)

[Scope of Claims] 1. Image transmission means for transmitting information obtained by scanning a screen as image information by band compression coding; A character transmission means for encoding and transmitting information; a mode switching means for selecting and using the above two means by mode switching; and control means for automatically switching to the mode of the image transmission means and rescanning and transmitting the position of the corresponding character when detecting the character.