JPH0468970A - Facsimile device - Google Patents

Abstract

PURPOSE: To simplify the operation of facsimile equipment by discriminating an original, whether it is a character original or not, from the pattern of the original and giving a fixed value when the original is a character original or a threshold group which changes according to a prescribed rule when the original is not any character original as a binarized threshold. CONSTITUTION: When the densities of lines in a line group composed of a prescribed number of lines on which the analog data corresponding to the picture density obtained when a picture is scanned continue are nearly equal to each other and line groups are regularly repeated, an original recognizing means 18 recognizes an original to be scanned as a character original and generates original facsimile data by binarizing the analog data with a prescribed threshold. Then the means 18 gives a fixed value to a character original or a threshold group which changes according to a prescribed rule to a non-character original as a threshold. Namely, the means 18 automatically sets a character original mode or a half-tone original mode. Therefore, a control panel 17 can be simplified or the operabflity of the panel 17 can be improved.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a facsimile device. Specifically, the present invention relates to an improvement in a binarization method when generating facsimile data.

[Conventional technology]

(1) Provides a facsimile device that generates facsimile data based on image scanning, reproduces images based on the facsimile data, and transmits and receives facsimile data, etc. to and from a destination device via a communication line network. has been done. (2) In the facsimile machine, the analog data corresponding to the image density obtained by image scanning is binarized by comparison with a binarization threshold and converted into digital data (original facsimile data). In the above, the binarization threshold is given a constant value for character manuscripts, and a dither pattern is given for manuscripts that require halftone expression, such as photographic manuscripts. A set of threshold values is provided that varies according to a predetermined rule. In other words, if it is a text manuscript, if it is composed of "black: text area" and "white, margin area", the darkness value for binarization is:
A good reproduced image is obtained by employing a value near the approximate intermediate value of the analog data corresponding to the 1iii image density obtained by image scanning. However, in the above-mentioned photographic manuscript, "black part - opposite part - white part" is continuously distributed. Therefore, when binarizing using a constant value, blackish parts (dark parts) become completely black, and whitish parts (bright parts) are reproduced as margins, making it impossible to obtain a good image. . In addition, as mentioned above, the binarization method is different depending on the type of document. Note that the designation of a text document or a photo document is performed by inputting from a predetermined key switch on the operation panel of the facsimile machine.

[Problems to be solved by the invention]

There is a demand for automatically specifying text or photographic documents instead of specifying them using a key switch. This is intended to simplify the operation panel and improve operability. The present invention aims to meet such demands.

[Means for solving the gap H point]

According to the present invention, analog data corresponding to image density obtained by image scanning is detected as a substantially uniform density for a predetermined number of continuous line groups, and the line groups detected as substantially uniform density are regularly detected. , a document recognition means that recognizes the document to be scanned as a text document, a binarization processing device that binarizes the analog data with a predetermined darkness value to generate original facsimile data, and a document recognition device that recognizes the document to be scanned as a text document; The facsimile apparatus is provided with a threshold data management means for providing a constant value for non-text documents and a group of threshold values that vary according to a predetermined rule for non-text documents as the predetermined thresholds. Note that the original facsimile data is digital data corresponding to the 111m density and does not include the control hood, etc. necessary for IS reproduction.

[Effect]

In the case of the letter W, as shown in FIG. 1, the character portion and the margin portion are repeated at predetermined intervals. others,! 6,1
Every few lines of the lli image scan, a line group with substantially uniform density (margin B) and a line group with randomly changing density (character area) are repeatedly detected alternately. Therefore, if the density of the document read by image scanning is approximately uniform over several consecutive lines and changes irregularly over the next several lines,
The document is recognized as a text document. In addition, when it is recognized as a text manuscript, the constant value becomes 2.
It is given as the value threshold. On the other hand, if it is recognized as a non-text document, a value that changes according to a predetermined rule, such as a dither pattern, is given as a threshold for binarization. That is, the character manuscript mode or the standard draft manuscript mode is automatically set.

【Example】

Below, an embodiment of the present invention will be described. FIG. 2 is a block diagram showing the circuit configuration of the facsimile machine 10 according to the embodiment. As shown in the figure, the facsimile machine 10 has an automatic call receiving section 1.
1, converter 12, line interface 00 path 13,
facsimile modem 14, facsimile transmission/reception section 15,
It has a facsimile control section 16, an operation panel 17, an image reading section 18, and an image recording section 19. When an incoming call from the communication line side is detected, the automatic incoming call unit 11 transmits an incoming call signal to the facsimile control unit 16 . The converter 12 connects the communication line and the line interface circuit 13 in response to a connection command signal from the Facunmill control unit.
Connect with. The facsimile modem 14 includes a facsimile transmitting/receiving section 15
The facsimile data input from the line interface circuit 13 is converted into data for the line and output to the line interface circuit 13, and the data input from the line interface circuit 13 is converted to facsimile data and sent/received via the facsimile 15. Output to. The fac/millimeter transmitting/receiving section 15 includes a facunmillimeter modem 14.
The image recording section 19 is driven in accordance with the facsimile data input from the image reading section 18 to reproduce the image on recording paper, and the facsimile data input from the image reading section 18 is processed and sent to the facsimile modem 14. Output etc. The facsimile control B16 transmits a connection command signal to the converter 13 in response to an incoming call signal from the automatic call receiving section 11, an off-hook command signal from the operation panel 17, and the like. It also performs various types of management such as the management of facsimile machines and communication lines. The operation panel 17 includes a group of numeric keys for manually inputting the selection number of the destination device, various key switches such as a fax key for commanding the off-footer operation, a display section for displaying a predetermined message, etc. has been done. The image reading unit 18 includes, for example, a CCD line sensor, a signal processing circuit for the line sensor, a document set detection sensor, a document feeding device, a memory, a CPU for braking, and the like. The image reading unit 18 scans the image of the set document,
Generation of analog data corresponding to one image by image scanning,
Based on the analog data, a determination is made as to whether or not the original is a text document, and a binarization process based on the determination is performed. Note that details will be described later. The image recording section 19 includes, for example, a print head, a drive circuit for the print head, a recording paper feeding mechanism, a bitmap memory, a control CPU, and the like. Image record 1fl! At step 19, an image reproduction operation is performed on the recording sheet based on the facsimile data. Next, the determination of text/non-text originals will be explained. Note that this determination is performed by the CPU for controlling the image reading 18. For example, when image scanning is started by setting a document, data corresponding to an analog value of image density is stored in the memory. Based on the image density, an average density value is calculated for each line. Information regarding density changes is also calculated on a line-by-line basis. Next, based on the average concentration calculated for each line,
A change in density in the sub-scanning direction (direction perpendicular to the lines) is determined. As a result, every few lines, there are areas where the average density value is bright and the density does not change much, and areas where the average density value is dark.
In addition, if an area with a relatively large density change is repeated, the document is determined to be a character document, and the process is performed in step 211 [
A constant value serving as a threshold value is given to perform binarization processing on the image density. On the other hand, in cases other than the above, the document is determined to be a halftone document, and a dither pattern, for example, is applied as a binarization threshold. In this way, original facsimile data is generated by performing the 21m conversion process, and a control code and the like are added to it and sent to the facsimile transmission/reception trust 15 as facsimile data. [Effects of the Invention] As described above, the present invention determines whether or not the document is a text document based on the document pattern, and sets a constant value for a text document, and a dither value for a non-text document, for example. pattern,
This is a facsimile machine that provides each as a threshold value for binarization. According to the present invention, by setting a document and operating a fax key or the like, an image is automatically read as a character document or a halftone document. The above configuration is also simplified.

[Brief explanation of drawings]

FIG. 1 is a detailed explanatory diagram of the present invention, and FIG. 2 is a circuit configuration diagram of an embodiment device.

Claims (1)

[Claims] A facsimile machine that generates facsimile data based on image scanning, reproduces an image based on the facsimile data, and transmits and receives facsimile data, etc. to and from a destination device via a communication line network. An apparatus, wherein analog data corresponding to image density obtained by image scanning is detected as substantially uniform density for a predetermined number of consecutive line groups, and the line group detected as substantially uniform density is If the scanning is repeated regularly, the original facsimile data is converted into original facsimile data by using a document recognition means that recognizes the document to be scanned as a text document, and by converting the analog data corresponding to the image density obtained by image scanning into binarized data using a predetermined threshold. A binarization processing means for generating the binarization processing means, and a threshold data management means for giving a constant value as a predetermined threshold value for text manuscripts, and a threshold value group that changes according to a predetermined rule for non-text manuscripts. Facsimile machine with.