JPH05130371A - Facsimile equipment - Google Patents

Abstract

PURPOSE:To reduce the communication cost by reducing total data quantity without losing original character and line segment information so as to reduce the transmission time and to improve received picture quality. CONSTITUTION:Analog video data resulting from reading a transmission original are converted into digital data by an A/D converter section 12 of a scanner section 2 and a binary section stores data to an FIFO memory section 14 as binary data. A dot detection section 16 detects a dot area based on picture information of the FIFO memory section 14 and the address is stored by a dot area latch section 17. An in-dot are line segment extract section 18 eliminates dots in the dot area and extract original character/line segment information and a switching synthesis section 15 selects either an output of the in-dot are line segment information or the picture information from the FIFO memory section 14 to synthesize the picture information.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a facsimile machine, and more particularly, to a facsimile machine for transmitting a transmission original in which halftone processing and gray processing are applied on characters and line segments.

[0002]

2. Description of the Related Art In recent years, with the rapid spread of word processors, a considerable portion of documents in general offices have become word processing documents. Therefore, most of the transmitted documents for office facsimiles are also occupied by word processing documents. By the way, a general word processor is provided with a halftone processing function of superposing halftone dots on characters and line segments. This shading process can be distinguished from other sentences at a glance if it is applied to an area to be emphasized in a created document, and can easily attract the attention of a person who reads the sentence, and also the shading process operation can be performed. Since it can be done with one key operation, it was often used in a complicated manner.

For this reason, conventionally, even a document image which has been subjected to halftone processing or the like has been transmitted using the facsimile apparatus as it is.

[0004]

However, in such a conventional facsimile apparatus, when a document image which has been subjected to a halftone processing is transmitted as it is by the facsimile apparatus, a white image having a short pitch is produced in the halftone area. Since the black pattern and the black pattern are alternately continuous, there is a problem that the data compression efficiency is greatly reduced, the transmission time is increased, and the communication cost is increased.

Further, when the pitch of the halftone processing and the reading scanning pitch are deviated from each other, moire occurs, and it is impossible to reproduce a uniform halftone image on the receiving side, which deteriorates the received image quality. There was a problem. Further, when a word processor-created document which is shaded as described above is read using an optical reading device (OCR) directly or at a remote place via facsimile communication, dots in a shaded area become an obstacle. Therefore, there is a problem that the characters cannot be cut out or discriminated.

Further, in general office documents, most of the originals having a wide range of gradation expression such as photographs are the above-mentioned halftone-processed originals and originals in which important parts are painted with a marker pen. The number of expression gradations of such a document is composed of about three stages of black / white / constant gray or color uniform base color. For this reason, if halftone processing used for photographs etc. is specified when transmitting the above-mentioned original, the data amount will increase due to the reduction of the resolution of the character part and the dithering of the gray part etc. There was a problem that the time would be long.

The present invention has been made in view of the above-mentioned conventional problems, and even if characters or line segments of a transmission document are subjected to halftone processing or uniform gray or color processing, the original An object of the present invention is to provide a facsimile apparatus capable of reducing the total amount of data to reduce the transmission time, the communication cost, and the received image quality without damaging the character or line segment information. ..

[0008]

The invention according to claim 1 is
Image information storage means for reading the transmitted document and storing image information converted into digital data, halftone dot area detection means for detecting a halftone dot area in the stored image information, and the detected halftone dot area detection means. From the halftone dot area internal line segment extracting means for removing halftone dots in the halftone dot area of the accumulated image information based on the halftone dot area information and extracting only the line segment information, and the halftone dot area internal line segment extracting means And the output from the image information storage means to replace the halftone dot area portion of the stored image information with the extracted line segment information, and It is characterized in that only the halftone dots are removed from the image information while leaving the background line segment information.

According to a second aspect of the invention, there is provided frame information generating means for generating outer frame information of the halftone dot area based on the halftone dot area information detected by the halftone dot area detecting means, and the image information switching means. In addition to replacing the halftone dot area of the image information from the image information storage means with line segment information, the outer frame information of the halftone dot area from the frame information generating means is added. According to a third aspect of the present invention, a gray area detecting means for detecting a gray area of a halftone in the image information accumulated by the image information accumulating means, and the accumulated image information based on the detected gray area information. A gray area internal line segment extracting means for removing the gray area in the inside and extracting only the original line segment information,
It is characterized in that only the gray portion is selectively removed while leaving the background line segment information from the image information of the transmission document in which the gray area is drawn.

According to a fourth aspect of the present invention, the positional information of the halftone dot area or the gray area is transmitted to the receiving station side together with the image information,
It is characterized in that the receiving station side synthesizes the image information which has been subjected to the halftone processing or the halftone gray processing based on the halftone dot / gray area position information and outputs the synthesized image information to the plotter.

[0011]

According to the first aspect of the present invention, the halftone dot area which has been subjected to the halftone processing by the halftone dot area detecting means is detected from the stored read image information of the transmission document, and the image information of the halftone dot area is obtained based on the halftone dot area information. The line segment information is extracted by removing the halftone dots in the halftone dot area. Then, the output switching control is performed so that the extracted line segment information is combined with the halftone dot area of the image information of the transmission document. For this reason, only the shaded portions are removed without damaging the original image information, the received image quality becomes good, and the amount of transmission data can be reduced, so that the transmission time and the communication cost are reduced.

According to the second aspect of the present invention, the outer frame information of the halftone dot area indicating the position of the portion to be emphasized by the halftone is generated by removing the halftone portion and is combined with the image information. Therefore, the position information of the shaded area to be emphasized is transmitted to the other party while reducing the amount of transmission data. According to the third aspect of the present invention, not only the halftone-processed original document but also the original document which is ground-processed with a light color uniform color by a marker pen or the like for highlighting or uniform gray-based,
Since this is removed from the image information to be transmitted, the amount of transmission data is reduced and the transmission time and communication cost are reduced.

According to the fourth aspect of the invention, the position information of the halftone dot area or the gray area is transmitted to the receiving station side together with the image information to be transmitted, and the receiving station side shades based on the halftone dot / gray area positional information. Processing or halftone gray processing is performed, and the background processing portion of the transmission original is reproduced on the receiver side. Therefore, the amount of data being transmitted is almost the same for the originals that have been subjected to the half-tone processing or gray processing and the originals that have not been subjected to those processings, which reduces the transmission time and the communication cost and reduces the transmission time. The same shading and gray processing as the original can be applied to the received original.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. First, the configuration will be described. FIG. 1 is a block diagram showing the overall configuration of a facsimile apparatus according to the present invention. In the facsimile transmitter 1 shown in FIG. 1, the scanner unit 2 reads image information while conveying a document to be transmitted line by line, and outputs binary image data.

The plotter section 3 is sent from the other party 2
It receives the binarized image data and prints it on recording paper, and has a thermal head for printing on thermal recording paper, a plotter control unit for driving and controlling the thermal head, and the like. The data compression / reproduction unit 4 encodes and compresses the facsimile data to be transmitted, and transfers the compressed data to the communication control unit 8 described later. Further, at the time of reception, the compressed code data transmitted via the modem 7 described later is decoded and reproduced, and the data is transferred to the plotter unit 3.

The image memory 5 is a memory for temporarily storing the transmitted image information and the image information to be transferred. The network control unit 6 is connected to the line L and executes a communication procedure necessary for communication with the partner terminal when transmitting / receiving facsimile data. For example, connection and disconnection with a line, line current detection, dial tone detection, etc. are performed.

The modem 7 modulates and demodulates an image signal for transmitting and receiving data between the facsimile machines connected via the line L. The communication control unit 8 deciphers and understands the communication control information in the facsimile data, and carries out execution processing such as transmission control and error control. The operation unit 9 is equipped with various switches such as a one-touch key for inputting a command signal relating to various transmission information and a numeric keypad for registering the other party, and transmits a command signal input by an operator to each unit.

The system control unit 10 controls the operation of each unit by the CPU, the ROM executes the sequence of the entire facsimile apparatus according to the program stored in the ROM, and the RAM works when the CPU executes each program. An area and a temporary storage area are provided, and in addition, a clock oscillating section and an I / O control section for performing the above control operation are provided.

The data bus 11 is a data transmission line for exchanging data by connecting the respective parts of the facsimile machine. FIG. 2 is a block diagram of a scanner section showing an embodiment of the facsimile apparatus according to the invention of claim 1. As shown in FIG. 2, the scanner unit 2 in this embodiment is subjected to processing such as DC reproduction, gain adjustment, and shading correction of image information of a transmission document read by a reading element such as a CCD (not shown). After that, the A / D converter 1
The digitized data is digitized by 2 and binarized by the binarization unit 13. At this time, binarization is performed at a fixed threshold level during binary reading, and binarization is performed at a variable threshold level during halftone reading.

Next, the binarized data is temporarily stored in the FIFO memory unit 14 which is a buffer memory, and then sent to the data compression / reproduction unit 4 or the like in the next stage, where it is transmitted to the other party. In the present invention, as shown in FIG.
The halftone dot detection unit 16 operates based on the image data from the FO memory unit 14, determines whether or not the halftone dot area is halftone-processed in a certain area, and detects this. The address of the halftone dot area detected by the halftone dot detecting unit 16 is held by the halftone dot area holding unit 17. Several proposals have already been made for the configuration of the halftone dot detection unit 16, and for example, the configurations described in JP-A-2-42872 and JP-A-2-53185 can be used. , But not limited to this.

Then, in the halftone dot area line segment extraction unit 18,
Based on the image information in the halftone dot area from the FIFO memory unit 14, the enable signal from the halftone dot area holding unit 17 extracts the character or line segment in the halftone dot area and performs the halftone dot erasing process. Be seen. As a result, only line segment information is extracted from the image in which the background white halftone information and the character / line segment information are mixed. The configuration of the halftone dot area line segment extracting unit 18 will be described with reference to FIG.

FIG. 3 is a block diagram showing an embodiment of the halftone dot area line segment extracting unit of FIG. As shown in FIG.
The halftone dot area line segment extracting unit 18 of the present embodiment includes a halftone dot pattern matching detecting unit 19, a white data replacing unit 20, and a smoothing processing unit 21. From the image information from the FIFO memory unit 14, the data in the halftone dot area is extracted by the halftone dot pattern matching detection unit 19. Then, based on the data in the halftone dot area from the halftone dot pattern matching detecting portion 19, the white data replacing portion 20 uses the halftone dot pitch signal from the halftone dot area holding portion 17 to isolate an isolated point (halftone dot or less). ) Is replaced with white data. For this reason,
In the white data replacement process, part of the character / line segment information is also replaced with white data, and the character / line segment information deteriorates. Therefore, in the present embodiment, the smoothing processing unit 21 performs smoothing processing to restore the deteriorated character / line segment information, and outputs it to the switching synthesis unit 15 in the next stage. Note that the halftone dot area line segment extraction unit 18 is not limited to the above configuration.

Returning to FIG. 2 again, in the switching synthesizing unit 15,
The image information is synthesized while switching the image information input from the FIFO memory unit 14 and the character / line segment information input from the halftone dot area line segment extraction unit 18 in which only the halftone dot information in the halftone dot area is removed. To be done. As a result, the image information from which only the halftone dot information in the halftone dot area has been removed is sent to the data compression / reproduction unit 4 in the next stage, so that the reduction of the data compression rate due to the halftone dots is prevented and the transmission data amount is reduced. The increase can be suppressed, the transmission time can be shortened, and the communication cost can be reduced.

Next, the operation will be described. 4A and 4B are explanatory diagrams of an image state in which the data processing according to the invention described in claim 1 is performed. FIG. 4A is an example of a transmission original image, and FIG. 4B is an example of a received original image. As shown in FIG. 4A, of the character portions 24 described on the transmission original 22, characters to be emphasized (here, B, D, E, G) are shaded like a shaded portion 25. Has been processed.

Therefore, in the embodiment described in claim 1, when the facsimile apparatus on the transmitter side reads the transmission original 22 and performs the above processing, only the halftone dot information is removed while the character information remains. 4 (b) is converted into image information, which is data-compressed and transmitted to the other party, so that the transmission data amount can be reduced without degrading the image quality. The shaded portion 25 is removed from the received document 23 printed out on the receiver side.

FIG. 5 is a block diagram of a scanner section showing an embodiment of a facsimile apparatus according to the invention of claim 2. As shown in FIG. 5, the scanner unit 2 according to claim 2.
2 is obtained by adding an area outer frame generating unit (frame information generating means) 26 for generating outer frame information of a halftone dot area to the configuration of claim 1 of FIG. The area outer frame generation unit 26 generates a frame with a thin line on the outer peripheral portion of the detected halftone dot area. The generated outer frame information is added and combined by the switching composition unit 15.

FIGS. 6A and 6B are explanatory diagrams of an image state in which the data processing according to the second aspect of the present invention has been performed. FIG. 6A is an example of a transmission original image, and FIG. As shown in FIG. 6A, when the highlighted portion on the character portion 24 of the transmission manuscript 22 is processed like the shaded portion 25, the above processing is performed to obtain the result shown in FIG. As shown in the received document 23, the shaded portion 25 is removed, and the character portion 24 and the outer frame 2 are removed.
7 is formed and transmitted to the other party.

As described above, in the embodiment according to claim 2,
In addition to the effect described in claim 1, the halftone dot information, which lowers the data compression efficiency, is removed, and the outer frame information that can be displayed with a small amount of information is added. Can be transmitted to the other party without. FIG. 7 is a block diagram of a scanner section showing an embodiment of a facsimile apparatus according to the invention of claim 3. Figure 7
2, the scanner unit 2 of claim 3 additionally includes a uniform gray area detection unit (gray area detection means) 28 in the configuration of claim 1 of FIG. 2, and replaces the halftone dot area holding unit 17. The halftone dot / uniform gray area holding unit 29 and the halftone dot / uniform gray area inner line extraction unit 30 are used instead of the halftone dot / uniform gray area inner line extraction unit 18.

By adopting such a configuration, not only the shaded portion in claim 1 is removed to reduce the amount of transmitted data, but also the background portion is provided with a uniform gray or a background color by a marker pen or the like. Even in a transmission original, only uniform gray information can be removed without losing the character / line segment information. Further, as shown in FIG. 7, the information of the halftone dot area and the uniform gray area detected by the halftone dot / uniform gray area holding unit 29 can be transmitted to the other party together with the image information via the communication control unit 8. ..

FIG. 8 is a block diagram showing an embodiment of a receiver of a facsimile apparatus according to the invention of claim 4.
As shown in FIG. 7, the halftone dot of the facsimile transmitter 1 /
The position information of the halftone dot area and the uniform gray area transmitted from the uniform gray area holding unit 29 together with the image information is sent to the facsimile receiver 31 via the line L shown in FIG. One image information is demodulated by the modem 33 via the network control unit 32, the compression code data is decoded by the decoding unit 34, and is temporarily stored in the bitmap memory 35.

The position information of the other halftone dot area or uniform gray area is demodulated by the modem 33 via the halftone dot control section 32, stored in the halftone dot area address holding section 36, and then the halftone dot generation section 37.
Is shaded. Then, the bitmap memory 35
The data from the halftone dot generation unit 37 is combined by the combining unit 38 and printed by the plotter unit 39.

As described above, since the facsimile data transmitted through the line L does not include the halftone dot information and the uniform gray information, it can be transmitted without lowering the data compression efficiency, and the receiver side can perform the halftone dot area. Since the image is reproduced based on the position information of the uniform gray area, it is possible to transmit an image that is almost the same as the transmission original image.

[0033]

According to the first aspect of the present invention, the halftone dot area is detected from the image information of the transmission original, only the line segment information is extracted while removing the halftone dot in the halftone dot area. Since it is combined with the image information of the transmission original document, the shaded portion can be removed without impairing the original character / line segment information. In this way, in the image information from which the shading is removed, the data compression rate is improved and the transmission data amount is reduced, so that the transmission time and the communication cost can be reduced. Also, since moire does not occur in the received image, good image quality can be obtained. Furthermore, the facsimile apparatus of the present invention is
It can also be used as a "shading removal copier" for removing the shaded portion, and the original can be shaded and processed during OCR processing.

According to the second aspect of the present invention, since the halftone dots in the halftone dot area are removed and the outer frame information is generated and combined with the image information, in addition to the effect of the first aspect, Location information can also be sent to the other party. According to the third aspect of the present invention, not only the halftone-processed original but also the original subjected to the ground processing with a light color uniform color or uniform gray with a marker pen or the like is left with the character / line segment information. , These can be removed.

According to the fourth aspect of the invention, the position information of the halftone dot / gray area is transmitted to the receiving station together with the image information from which the halftone dots or uniform grays have been removed, and the receiving station side performs the network based on the position information. Since the cross processing or the gray processing is performed, the same image as the transmission original can be transmitted and reproduced without increasing the transmission data amount.

[Brief description of drawings]

FIG. 1 is a block diagram showing an overall configuration of a facsimile apparatus according to the present invention.

FIG. 2 is a block diagram of a scanner unit showing an embodiment of a facsimile apparatus according to the invention of claim 1;

FIG. 3 is a block diagram showing an embodiment of a halftone dot area line segment extracting unit in FIG. 2;

FIG. 4 is an image state explanatory diagram in which data processing according to the invention of claim 1 is performed, (a) is an example of a transmission original image,
(B) is an example of a received document image.

FIG. 5 is a block diagram of a scanner section showing an embodiment of a facsimile apparatus according to the invention of claim 2.

FIG. 6 is an image state explanatory diagram in which data processing according to the invention of claim 2 is performed, (a) is an example of a transmission original image,
(B) is an example of a received document image.

FIG. 7 is a block diagram of a scanner section showing an embodiment of a facsimile apparatus according to the invention of claim 3;

FIG. 8 is a block diagram showing an embodiment of a receiver of a facsimile apparatus according to the invention of claim 4;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Facsimile transmitter 2 Scanner section 14 FIFO memory section (image information storage means) 15 Switching composition section (image information switching means) 16 Halftone dot detection section (halftone dot area detection means) 17 Halftone dot area holding section 18 Halftone dot area extension line Segment extraction unit (halftone dot region internal line segment extraction unit) 26 Region outer frame generation unit (frame information generation unit) 28 Uniform gray region detection unit (Gray region detection unit) 29 Halftone dot / uniform gray region holding unit 30 Halftone dot / uniform Gray area inner line segment extraction unit (gray area inner line segment extraction means) 36 Halftone dot area address storage unit 37 Halftone generation unit 38 Compositing unit 39 Plotter unit

Claims (4)

[Claims] 1. An image information storage means for storing image information obtained by scanning a transmission original and converting it into digital data, and a halftone dot area detecting means for detecting a halftone dot area in the stored image information. A halftone dot area line segment extracting means for removing halftone dots in the halftone dot area of the stored image information based on the detected halftone dot area information and extracting only line segment information; and the halftone dot area Image information switching means for switching the output from the internal line segment extraction means and the output from the image information storage means to replace the halftone dot area portion of the stored image information with the extracted line segment information; A facsimile apparatus, which removes only halftone dots while leaving background line segment information from image information of a transmitted transmission document. 2. A frame information generating means for generating outer frame information of a halftone dot area on the basis of the halftone dot area information detected by the halftone dot area detecting means, wherein the image information switching means changes the image information storing means from the image information storing means. 2. The facsimile apparatus according to claim 1, wherein the halftone dot area of the image information is replaced with line segment information and the outer frame information of the halftone dot area from the frame information generating means is added. 3. Gray area detection means for detecting a halftone gray area in the image information accumulated by the image information accumulation means, and gray in the accumulated image information based on the detected gray area information. A gray area internal line segment extraction means for removing the area and extracting only the original line segment information is provided, and the gray portion is retained while leaving the background line segment information from the image information of the transmission document in which the gray area is drawn. The facsimile apparatus according to claim 1 or 2, wherein only the selected one is selectively removed. 4. The position information of a halftone dot area or a gray area is transmitted to a receiving station side together with image information, and the receiving station side performs halftone processing or halftone gray processing based on the halftone dot / gray area positional information. The image information is combined and output to a plotter.
The described facsimile machine.