JPH08204962A - Facsimile equipment - Google Patents

Abstract

PURPOSE: To provide a facsimile equipment which can automatically select one of two or more different half tone processing systems in response to the recording line density of the facsimile equipment of the opposite party that receives the binarized image data transmitted in facsimile. CONSTITUTION: This facsimile equipment is provided with an original reading part 11, two or more half tone processing parts 10 which correspond to the binarization processing systems of different half tones, an operation input part 14 which includes the buttons that designate the copy and transmission operations, a modem 17 which performs the communication with the facsimile equipment of the transmission destination side via a transmission circuit, and a circuit control part 18. Then a CPU 10 sends the output of one of parts 10 to the modem 17 as the transmission data based on the output of the part 14 and the information on the facsimile equipment of the destination side that is outputted from the modem 17.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a facsimile apparatus capable of binarizing an image containing a read halftone density by two or more different processing methods.

[0002]

2. Description of the Related Art Generally, a facsimile apparatus reads an original by a reading apparatus, transmits the image data obtained by the original to another facsimile apparatus via a telephone line or the like, and the facsimile apparatus which receives the image data receives the image data. The received image data is recorded by a printing device such as a printer.

Here, since the image data to be transmitted is binary data in which each pixel is black and white, when the image data obtained by reading the original by the reading device includes a halftone density, the image data is read. It is necessary to binarize the image data. As this binarization method, various processing methods typified by a pseudo gradation expression method called a dither method and an error diffusion method are known.

In the dither method, one pixel of a halftone density is made to correspond to a minute area composed of a plurality of black and white binary pixels, and by changing the density of black pixels in this minute area, the halftone density is changed. This is a method of expressing light and shade. In the error diffusion method, when the read halftone pixel is binarized, as the density to be compared with the threshold value, the density before binarization and the value after binarization of the already binarized adjacent pixel are used. Considering the error with
This is a method using a corrected density obtained by correcting the density of a halftone pixel to be binarized.

[0005]

However, the conventional facsimile apparatus has the following problems. That is, in general, the conventional facsimile apparatus uses any one of these halftone density binarization processing. However, each processing method has a difference in image quality and transmission / reception time. Since there are advantages and disadvantages, depending on the usage situation when sending, copying, etc.,
When transmitting, one processing method may or may not be suitable depending on the recording accuracy of the receiving facsimile machine.

For example, when the dither method is used, the transmission time of image data can be shortened as compared with the case where the error diffusion method is used. However, the image data has higher image quality when the error diffusion method is used. Also,
In the case of a facsimile machine that selects and processes a plurality of processing methods, it is necessary for the operator to select each processing method. In this case, the processing is performed in consideration of the accuracy of the recording device of the facsimile machine that receives data during transmission. It was not possible to choose the method.

The present invention has been made in view of the above circumstances, and it is possible to select from two or more different halftone processing methods according to the recording linear density of the other device which receives the binary image data transmitted by facsimile. An object of the present invention is to provide a facsimile machine that automatically selects one processing method. Further, when a document is read and stored in the storage means, the read image is automatically binarized by the error diffusion method and stored in the storage means. Another object of the present invention is to provide a facsimile apparatus which can automatically binarize a read image by a dither method and store it in a storage means.

[0008]

According to a first aspect of the present invention, a facsimile apparatus according to the present invention has a reading unit for reading a document and two or more halftone processings corresponding to different halftone binarization processing systems. Section, an operation input section having buttons for designating copy and transmission, a modem and a line control section for communicating with a destination facsimile machine via a transmission line, an output of the operation input section and an output from the modem. And a central processing unit for outputting to the modem any of the outputs of the halftone processing units as transmission data based on the information of the destination facsimile machine.

In the facsimile apparatus according to the present invention as defined in claim 2, the halftone processing unit of the facsimile apparatus according to the present invention as defined in claim 1 has at least a resolution of 400.
Halftone processing unit for performing binarization processing by an error diffusion method of dpi × 400 dpi and resolution of 200 dpi × 200
It is configured by a halftone processing unit that performs a binarization process by the dither method of dpi.

According to a third aspect of the present invention, there is provided a facsimile apparatus for reading an original document, and at least two halftone processing units using an error diffusion method and a dither method.
Storage means for storing image data after binarization processing, operation input section equipped with buttons for designating copy and transmission, modem and line control for communicating with destination facsimile machine via transmission line Section, a recording section for printing the binarized image data, and a central processing section for outputting the binarized image data to the storage means based on the output of each halftone processing section and the operation input section. It

[0011]

In the facsimile apparatus according to the present invention as set forth in claim 1, the reading section reads the original as an image including halftone density, and each halftone processing section binarizes the read image data by each processing method. Convert to. On the other hand, the information of the destination facsimile machine transmitted from the destination facsimile machine is transmitted via the transmission line, the line controller and the modem.
Received by the central processing unit. The central processing unit determines an appropriate halftone processing method based on the recording linear density of the recording unit of the destination facsimile machine included in the received information, and the binarized data output from the halftone processing unit. Is output as transmission data to the modem, the modulated binary image data is sent to the facsimile machine of the other party via the line control unit and the transmission line.

In the facsimile apparatus according to the present invention as defined in claim 2, when the recording linear density of the recording section of the facsimile apparatus of the other party is 400 dpi, the central processing section uses the error diffusion processing section to obtain a resolution of 400 dpi × 400 dpi.
The data that has been binarized by the error diffusion method of i is output to the modem as transmission data, and if it is 200 dpi, the data that has been binarized by the dither method with a resolution of 200 dpi × 200 dpi by the dither processing unit is transmitted to the modem. Output as.

In the facsimile apparatus according to the present invention, when the operation input section outputs a signal for copying, the central processing section copies the output of the halftone processing section by the error diffusion method. Image data to be stored in the memory. On the other hand, when a signal for facsimile transmission is output from the operation input unit, the central processing unit stores the output of the halftone processing unit using the dither method in the memory as image data for transmission.

The resolution of 400 dpi × 400 dpi means that the resolution in the main scanning direction is 400 dpi (dot pe).
r inch) and the resolution in the sub-scanning direction is 400d.
It means a resolution such as pi.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an example of the construction of a facsimile apparatus according to the present invention as defined in claims 1, 2 and 3. This facsimile device 1 is output from a central control unit 10 that controls the entire facsimile, a reading unit 11 that can optically read a document to be transmitted or copied as halftone density image data, and a reading unit. A plurality of halftone processing units 1 for converting image data into white or black binary data
2a, 12b, 12c, and an operation input unit 13 having an input means B for designating copy, transmission, and halftone.
A recording unit 14 for applying heat in dot units according to the binarized image data to print on the thermal paper, and a program and data required for the operation of the central processing unit.
OM15 and RAM for storing data including image data
16, a modem 17 that performs modulation / demodulation processing, and a line control unit 18 that controls a line.

The reading unit 11 detects the reflected light of the light emitted from the light source to the original document by the CCD, and outputs the image data as a gradation signal according to the original reading density of the original document. The halftone processing units 12a, 12b, and 12c binarize the image data represented by the density output from the reading unit 11 with gradation, that is, the image data including the halftone density into white or black. Convert to data. The facsimile apparatus 1 usually has three different types of halftone processing units, which are a binarization method, an error diffusion method, and a dither method.

The normal binarization processing section 12c is a processing section which compares the pixel density with a constant threshold value and binarizes it by the method of making it black or white depending on its height. This is a halftone processing unit that performs the simplest processing that is not available.
The error diffusion processing unit 12a is a halftone processing unit that performs binarization by the above error diffusion method with the resolution in the main scanning direction set to 400 dpi and the resolution in the sub scanning direction set to 400 dpi. The dither processing unit 12b is a halftone processing unit that performs binarization with the resolution in the main scanning direction set to 200 dpi and the resolution in the sub scanning direction set to 200 dpi by the above-described dither method.

The operation input unit 13 outputs to the central processing unit 10 information in which the operator of the facsimile apparatus 1 has instructed the presence or absence of facsimile transmission or copying and halftone processing by button operation. FIG. 2 shows a flowchart of the basic operation of the facsimile apparatus 1 in the case of the scanner transmission in which the document is read and then immediately transmitted.

The central processing unit 10 of the facsimile machine detects the digital identification signal (DIS signal) containing the information of the receiving function of the receiving machine, and then the digital command signal (D
A CS signal) and a training signal. here,
For signal reception, the modem 17 demodulates the signal of the transmission line via the line control unit 18, and the output signal of the modem is processed by the central processing unit 1.
0 detects. On the other hand, for signal transmission, the modem 17 modulates the transmission signal output from the central processing unit 10, and the line control unit 18
To the transmission line via.

The central processing unit 10 checks, based on the output of the operation input unit 13, whether or not the halftone processing is designated as the transmission mode. As a result, when the halftone is not designated, the central processing unit 10 normally uses the binary processing unit 12c.
Is output to the modem 17 as transmission data. On the other hand, as a result of the above inspection, when the halftone is designated, the error diffusion processing unit 12 is determined based on the receiving function of the partner device.
Either a or the output of the dither processing unit 12b is selected as the transmission data.

That is, when the recording linear density of the recording means of the partner device is 400 dpi based on the information of the receiving function of the partner device, the output of the error diffusion processing section 12a is output to the modem 17 as transmission data, When the recording linear density of the recording means of the machine is not 400 dpi, the output of the dither processing unit 12b is output to the modem 17 as transmission data. After the transmission of all of the binarized image data by any of the above methods is completed, a post message is sent to complete the transmission.

Therefore, when halftone processing is designated,
If the other device is equipped with a high-quality recording unit, the high-quality data of 400 dpi × 400 dpi processed by the error diffusion method can be transmitted to effectively use the capability of the recording means and 200 dpi × processed by dither method when the recording unit for image quality is not provided
High-speed data transmission can be achieved by transmitting 200 dpi data.

Next, after the original is read, if the binarized image data is stored and stored in the RAM without being immediately transmitted, or when the copy operation is performed, the printing is not performed immediately. FIG. 3 is a flowchart showing the basic operation of the facsimile apparatus when the image data after the binarization processing is stored in the RAM and stored, that is, when the image data after the binarization processing is stored and stored in the RAM. Show.

First, the central processing unit 10 checks, based on the output of the operation input unit, whether or not the halftone processing is designated. As a result, when the halftone is not designated, the central processing unit 10 stores the output of the normal binarization processing unit 12c in the RAM 16. On the other hand, when the halftone is designated, it is further inspected based on the output of the operation input unit 13 whether or not the operation is a copy operation. As a result, if the operation is a copy operation, the error diffusion processing unit 1
The output of 2a is stored in the RAM 16, and the output of the dither processing unit 12b is stored in the RAM 16 when not operating as a copy, that is, when operating as a facsimile transmitter.

Therefore, at the time of operation as a copy, 400 dpi × 400 dpi processed by the error diffusion method.
By storing the high quality image data in RAM in the RAM, the image quality is prioritized to enable the high quality copying, and in the case of the facsimile transmission, it is processed by the dither method.
By accumulating the data of 00 dpi × 200 dpi in the RAM, the reduction of the communication time can be prioritized over the image quality of the transmission data.

[0026]

According to the first aspect of the present invention, the facsimile apparatus according to the present invention automatically selects and transmits the halftone processing method of the read image data based on the recording linear density of the recording means of the partner machine. Therefore, it is possible to automatically select an appropriate halftone process according to the recording capability of the other device.

That is, for a partner machine having a high recording linear density, a high-quality halftone processing method is selected, and facsimile transmission with priority on image quality is performed to waste the performance of the recording means of the partner machine. Instead, a halftone processing method that enables effective utilization and has a low recording linear density and selects a halftone processing method that can reduce the transmission time is performed, and the facsimile transmission with priority on the communication time is performed.

In the facsimile apparatus according to the present invention as defined in claim 2, the recording linear density of the recording means of the partner machine is 400d.
In case of pi, 400 dpi × 40 by error diffusion method
If halftone processing with a resolution of 0 dpi is automatically selected and facsimile transmission with image quality priority is performed, and the recording linear density of the recording means of the other device is not 400 dpi, halftone processing with a resolution of 200 dpi × 200 dpi by dithering is performed. Facsimile transmission with priority given to shortening transmission time is automatically selected.

In the facsimile apparatus according to the third aspect of the present invention, when the read original is stored in the storage means, the copy original is stored in the storage means after being subjected to halftone processing by the error diffusion method. Therefore, the image quality is prioritized during copying, and the transmission original is stored in the storage unit after halftone processing is performed by the dither method. Therefore, during facsimile transmission, the transmission time is prioritized over image quality. You can

[Brief description of drawings]

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

FIG. 2 is a diagram showing a flowchart of a basic operation of the facsimile apparatus according to the present invention described in claims 1 and 2.

FIG. 3 is a diagram showing a flowchart of a basic operation of the facsimile apparatus according to the present invention as defined in claim 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Facsimile apparatus 12a ... Halftone processing unit by error diffusion method 12b ... Halftone processing unit by dither method 12c ... Normal binarization processing unit 16 ... Storage means

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location H04N 1/403 H04N 1/40 103 A

Claims (3)

[Claims] 1. A method of processing two or more different halftones,
A facsimile apparatus capable of binarizing image data including read halftone density and transmitting the binarized image data,
A facsimile apparatus, wherein the halftone processing method is selected according to the recording linear density of the facsimile apparatus that receives the transmitted binary data. 2. When the recording linear density of a facsimile apparatus that receives binarized image data is 400 dpi, the read image data is binarized by an error diffusion method with a resolution of 400 dpi and transmitted. In the other cases, the facsimile apparatus according to claim 1, wherein the facsimile apparatus performs binarization processing by a dither method with a resolution of 200 dpi and then transmits the data. 3. With two or more different halftone processing methods,
A facsimile device capable of binarizing read image data including halftone density and storing the binarized image data in a storage unit. In the case of a copy original, the read image is binarized by an error diffusion method. A facsimile apparatus, which processes and stores in a storage means, and in the case of a document for transmission, binarizes a read image by a dither method and stores in a storage means.