JPH06169388A - Facsimile equipment - Google Patents

Abstract

PURPOSE:To determine whether the resolution of sent image information is converted or not according to a previously set resolution conversion necessity/ nonnecessity judgement criterion. CONSTITUTION:A reader 1 reads a document with resolution selected according to the indication of a picture quality indication part 92 and stores it in a image information memory 2. The indication contents are stored in a control memory 101. Transmission resolution is determined on the basis of resolution corresponding to the indicated picture quality and the resolving power of an opposite machine. When the transmission resolution is nearly equal to the resolution of the stored image information, it is decided on the basis of conversion necessity/nonnecessity information whether or not the resolution conversion is performed. Further, when the transmission resolution is nearly equal to the resolution of the stored image information, a communication mode decision part 19 decides a communication mode and does not convert the resolution of the image information when the mode is the mode G4.

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 suitable for reducing image quality deterioration in image communication with a partner station having different resolution capabilities.

[0002]

2. Description of the Related Art Currently, as a facsimile apparatus, G3
A communication mode standard (hereinafter referred to as G3 machine) and a G4 communication mode standard (hereinafter referred to as G4 machine) are used in a mixed manner. Further, with the increase in the amount of communication information, dual-purpose machines for G3 and G4 communication modes have also become popular. In these two types of facsimile machines, the G3 machine has a millimeter system, and the G4 machine has an inch system, and their resolutions are specified.

Therefore, when performing communication between facsimile apparatuses having different communication mode standards, it is necessary to perform resolution conversion according to the resolution capability of the partner station and then transmit the image information. For example, when transmitting image information read by the G4 machine in the inch system in the G3 communication mode, resolution conversion from the inch system to the millimeter system is performed.

By the way, when such resolution conversion is performed, the image on the receiver side is reproduced in the same size as the original image size, and the image is not distorted, but the image quality is deteriorated by dot thinning or insertion. There is a problem of doing.

With respect to this problem, it is determined whether the image quality of the output image is emphasized or the size, that is, the distortion of the image is emphasized according to the type of the document, and whether the resolution conversion is executed based on the determination. There is proposed a facsimile apparatus which determines the number (Japanese Patent Laid-Open No. 1-282961).

[0006]

The above-mentioned conventional facsimile machine has the following problems. That is, in the above-mentioned conventional apparatus, the operator determines whether or not to execute the resolution conversion by looking at the document. Therefore, the operator is required to perform the above-described determination and the key operation after the determination for each communication, which causes a problem that the operation becomes complicated.

Further, the G4 communication mode can exhibit its characteristics especially for high-speed communication, but there is a problem that its high speed is impaired by resolution conversion. Therefore, when determining whether or not to perform resolution conversion, it is necessary to consider a criterion for not performing resolution conversion in the G4 communication mode in order not to hinder high-speed communication, but this point has been taken into consideration in the past. Didn't.

Further, in the past, CCITT T.K. In the 30 recommendations, only the millimeter system was defined as the resolution, but the inch system was newly recommended. As a result, in communication with the G3 machine, the resolution of the image information read by the inch system may not be converted from the inch system to the millimeter system. The conventional device has a problem that no consideration is given to such a new technological trend.

The object of the present invention is to solve the above problems,
It is an object of the present invention to provide a facsimile apparatus that can automatically determine the necessity of resolution conversion of image information based on various judgment criteria without bothering an operator.

[0010]

According to the present invention for solving the above problems and achieving the object, a transmission resolution determined based on the resolution capability of a partner device and a resolution of accumulated transmission image information are A first feature is that when it is determined that they are substantially equal to each other, whether or not to perform resolution conversion of the accumulated image information is determined according to preset conversion necessity information. .

Further, according to the present invention, when it is determined that the transmission resolution determined based on the resolution capability of the other device and the resolution of the stored transmission image information are substantially equal to each other, the accumulated image information is stored. A second feature is that it is configured to determine whether to perform resolution conversion according to the communication mode.

[0012]

According to the present invention having the above characteristics, when the transmission resolution and the resolution of the stored image information are substantially the same, the necessity of resolution conversion is automatically determined according to preset conversion necessity information. It is determined.

Further, according to the present invention having the second feature, when the transmission resolution and the resolution of the stored image information are substantially equal to each other, the necessity of resolution conversion is automatically determined according to the communication mode. It is determined.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is a principal block diagram showing the hardware structure of the facsimile apparatus according to the present invention. In the figure, the reading apparatus 1 reads a transmission document and converts it into an electric signal, that is, image information. The image information read by the reading device 1 and the image information received from the outside are stored in an image information storage device (hereinafter, referred to as image information memory) 2. In the image processing device 3, the transmission image information is encoded and the reception image information is decoded. The received image information is recorded by the printer 12.

In the G3 communication control unit 4, control for performing facsimile communication in the G3 communication mode is performed.
The communication control unit 5 controls the facsimile communication in the G4 communication mode. Further, the G3 communication control unit 4 is connected to an analog line via the modem 6 and the analog network control device 7. On the other hand, the G4 communication control unit 5 is connected to the digital line via the digital network control device 8.

The operation / display device 9 includes operation switches for an operator to give an instruction to the facsimile device.
And a panel such as a liquid crystal display system for displaying the operating state. The ROM 10 stores a program for controlling the facsimile apparatus as a whole and a program for controlling the communication control units 4 and 5, the modem 6, and the network control apparatuses 7 and 8. The RAM 11 is a work area used for executing the program.

The CPU 13 has the ROM 10 and RA
According to the program and control data stored in M11, and the instruction input from the operation / display device 9, the control process and the transmission control procedure process of the entire facsimile device are executed. Data exchange between the above-mentioned components is performed via the system bus 14.

In the facsimile apparatus having the above-mentioned structure, the image information read by the reading device 1 is temporarily stored in the image information memory 2 and sent to the line in accordance with a transmission instruction input from the operation / display device 9. On the other hand, the image information received from the outside is decoded by the image processing device 3, accumulated in the image information memory 2, and recorded by the printing device 12. The facsimile communication is performed in either the G3 or G4 communication mode according to the instruction input from the operation / display device 9.

The transmission operation of the facsimile apparatus having the above hardware structure will be described with reference to the flowchart of FIG. In step S1, an image quality instruction and a reading instruction input from the operation / display device 9 are awaited.

If an instruction is detected, the process proceeds to step S2, the original is read at the resolution corresponding to the instructed image quality, and the read image information is stored in the image information memory 2. For example, if the image quality instruction is high image quality in the G3 communication mode,
Main scanning direction 8 lines / mm, Sub scanning direction 7.7 lines /
A resolution of mm (8 × 7.7 / mm) is selected and reading is performed.

In the G3 communication mode, the resolution is 16 × 15.4 / mm for super high image quality and 8 × 8.8 for high image quality.
7 / mm, standard image quality corresponds to 8 × 3.85 / mm resolution. In G4 communication mode, resolution is 400 × 400 pixels / inch for super high image quality and 200 for high image quality.
× 200 pixels / inch, resolution 200 × 1 for standard image quality
00 pixels / inch correspond to each.

In step S3, referring to the resolution conversion necessity table, the resolution conversion necessity information corresponding to the instructed image quality is read, and the conversion necessity information flag is set according to each resolution conversion information. An example of this resolution conversion necessity table is shown in FIG. 4A, and the data set in the flag corresponding to each conversion necessity information is shown in FIG. 4B.
The table is not limited to the correspondence shown in FIG. 4A, but can be set in advance to any correspondence.
1 or RAM 10 can be stored.

In step S4, a call is made in response to a communication instruction input from the operation / display device 9. Step S
In step 5, the reception of the digital identification signal DIS is awaited. When the digital identification signal DIS is received, the process proceeds to step S6, the expected bit of the facsimile information field FIF of the digital identification signal DIS is analyzed, and the resolution capability of the partner machine is identified. Then, in the case of having a plurality of resolution capabilities, the resolution that gives the same or the closest image quality as the image quality instructed in step S1 is determined as the transmission resolution.

In step S7, the determined transmission resolution is compared with the resolution of the stored image information (accumulation resolution) to determine whether they are the same. If they are not the same, the process proceeds to step S8, and it is determined whether the transmission resolution and the storage resolution are substantially equal. FIG. 5 shows the correspondence relationship of resolutions that are the criteria for determining whether or not they are substantially equal. For example,
When image information is read at a resolution of 8 × 7.7 / mm, the corresponding 200 × 200 pixels / inch (p
The resolution of pi) is regarded as almost the same resolution.

If the determination in step S8 is affirmative, the process proceeds to step S9, and it is determined whether the resolution needs to be converted based on the conversion necessity information. According to the resolution conversion necessity table (FIG. 4), "convert" corresponds to high image quality, and "1" is set in the flag in the process of step S3. Therefore, the determination in step S9 becomes affirmative, and the process proceeds to step S10 to convert the resolution of the stored image information into the transmission resolution. If the determination in step S8 is negative, step S9 is skipped and step S10 is performed.
Proceed to. When the resolution conversion of the image information is completed, the process proceeds to step S11 and the image information is transmitted.

If the image quality is designated as the ultra-high image quality or the standard image quality, it is judged from the resolution conversion necessity table (FIG. 4) that "no conversion" is performed, and in the process of step S3, the flag is set to " 0 ”is set. Therefore, the determination in step S9 is negative and step S10 is skipped.

On the other hand, if the determination in step S7 is affirmative, there is no need for resolution conversion, so steps S8-10
Skips and proceeds to step S11.

In the present embodiment, a resolution conversion table in which the resolution of the stored image information and the conversion necessity information are associated with each other is prepared. However, instead of this table, the resolution in which the transmission resolution and the conversion necessity information are associated with each other. A conversion table may be prepared. FIG. 6 is a diagram showing an example of a resolution conversion table in which transmission resolution and conversion necessity information (discrimination of presence / absence of conversion) are associated with each other.

When this resolution conversion table is used, step S3 in the flowchart of FIG. 3 is deleted, and in step S9, it is determined whether the conversion necessity information corresponding to the transmission resolution is "convert". It may be determined by referring to the table of No. 6.

Further, the communication mode is set to G3 instead of determining whether or not the resolution conversion is required according to the resolution conversion table.
Whether to convert the resolution may be determined depending on whether G4 or G4. That is, in the G4 communication mode, the communication speed is particularly important. Therefore, in this case, if the resolution of the stored image information and the transmission resolution determined by the negotiation with the other device are substantially equal, the resolution conversion is not performed and the image information is transmitted in the stored resolution as it is. In this case, step S3 in the flowchart of FIG. 3 may be deleted, and the process of determining whether the communication mode is G4 may be performed instead of the process of step S9.

Next, the main functions of the facsimile apparatus of this embodiment will be described with reference to the block diagram of FIG. In the figure, the same reference numerals as those in FIG. 2 indicate the same or equivalent parts.

The reading device 1 reads the transmission document according to the instruction output from the reading instruction section 91, and the image information is stored in the image information memory 2. The reading resolution at this time is determined corresponding to the instruction output from the image quality instruction unit 92. The communication control unit 4 or 5 calls the partner station in the communication mode instructed in response to the instruction from the communication instruction unit 93 and starts communication. The designated image quality, that is, the resolution data and the communication mode are stored in the management memory 101.

The transmission resolution determination unit 15 is the communication control unit 4
The capability information of the partner machine detected in (5) and the management memory 10
The resolution actually used for transmission (transmission resolution) is determined based on the designated resolution stored in 1.

The resolution comparison unit 16 compares the determined transmission resolution with the designated resolution, that is, the image quality designated at the time of reading. If the result of comparison between the two is "same", the comparison result signal s1 output to the conversion unit 17 is set to high "H". As a result, the image information output from the image information memory 2 in response to the signal s1 is resolution-converted by the conversion unit 17, and then sent to the line via the communication control unit 4 or 5.

If the comparison result is "substantially equivalent", the resolution comparing unit 16 stores "substantially equivalent" in the conversion necessity information storage unit 18.
Is supplied, and the conversion necessity information flag corresponding to the conversion necessity information is identified. An example of the conversion necessity information table stored in the conversion necessity information storage unit 18 is shown in FIGS. 4 and 6. The conversion necessity information corresponds to the instructed resolution or the determined transmission resolution. When the conversion necessity information is “convert”, that is, when the conversion necessity information flag is “1”, the signal s2 output to the conversion unit 17 becomes “H”. When the conversion necessity information is “not converted”, that is, when the conversion necessity information flag is “0”,
The signal s2 goes low "L".

When the comparison result in the resolution comparing section 16 is neither "identical" nor "substantially equal", both the signals s1 and s2 are "L". Therefore, the conversion unit 17
Does not perform the resolution conversion operation, and the image information read from the image information memory 2 is used as it is (through) in the communication control unit 4.
Or it is input to 5.

Further, when the comparison result in the resolution comparing section 16 is "substantially equal", a communication mode judging section 19 may be provided to judge whether or not the resolution conversion is performed according to the communication mode. The communication mode determination unit 19 does not perform resolution conversion in the G4 communication mode.
When a signal indicating "substantially equal" is supplied from the resolution comparison unit 16, the stored data is read from the management memory 101 and it is determined whether the communication mode is G4 or other modes. As a result of the determination,
The signal s3 is set to "L" when the communication mode is G4, and the signal s3 is set to "H" otherwise.

It should be noted that either one of the conversion prohibition information storage section 18 and the communication mode determination section 19 may be provided.

As described above, according to the present embodiment, when the instructed resolution and the transmission resolution are substantially equal to each other, the conversion necessity information stored in advance in correspondence with the accumulated resolution or the transmission resolution, or Whether to convert the resolution is determined based on the communication mode. That is,
The determination standard is set in advance in consideration of the deterioration of image information due to resolution conversion, the influence on the high speed, and the content of the transmitted document. Then, when the instructed resolution and the transmission resolution are substantially equal to each other, the resolution conversion is executed according to this criterion.

In this embodiment, the transmission of the image information read by the reading device and stored in the image information memory has been described. However, the image information previously stored in the image information storage device or the information of the host computer or the like is described. The image information supplied from the processing device can be transmitted in the same manner as this embodiment.

[0041]

As is apparent from the above description, according to the present invention, resolution conversion can be performed only when necessary according to a predetermined criterion, so that the influence on high-speed communication and the influence of image quality deterioration And so on,
The most desirable transmission form can be selected.

Further, whether or not to execute the resolution conversion can be automatically determined, and the operator's hand is not bothered.

[Brief description of drawings]

FIG. 1 is a block diagram showing a main function of a facsimile apparatus.

FIG. 2 is a block diagram showing a hardware configuration of a facsimile apparatus.

FIG. 3 is a flowchart showing the operation of the embodiment.

FIG. 4 is a diagram showing correspondence between resolution and conversion necessity information.

FIG. 5 is a diagram showing correspondence of resolutions that are interpreted as being substantially equivalent.

FIG. 6 is a diagram showing correspondence between transmission resolution and conversion necessity information.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Reading device, 2 ... Image information memory, 4, 5 ... Communication control part, 9 ... Operation / display device, 15 ... Transmission resolution determination part, 16 ... Resolution comparison part, 17 ... Conversion part, 18 ... Conversion necessity information Storage unit, 19 ... Communication mode determination unit, 91
... Read instruction section, 92 ... Image quality instruction section, 93 ... Communication instruction section, 101 ... Management memory

Claims (4)

[Claims] 1. A facsimile apparatus having a resolution conversion means for converting the resolution of stored image information and transmitting it to a partner machine, whether or not conversion is necessary to indicate whether or not to perform resolution conversion of stored image information. A conversion necessity information storage unit that stores information, and a resolution comparison unit that determines whether or not the transmission resolution determined based on the resolution capability of the other device and the resolution of the stored transmission image information are substantially the same. When the resolution comparing unit determines that the two resolutions are substantially equal to each other, it is configured to determine whether to perform resolution conversion of the accumulated image information based on the conversion necessity information. A facsimile device characterized by the above. 2. The facsimile apparatus according to claim 1, wherein the conversion necessity information is stored in correspondence with a resolution that can be instructed on the transmission side. 3. The facsimile according to claim 1, wherein the conversion necessity information is stored in correspondence with a transmission resolution determined by a resolution instructed by a transmission side and a resolution capability of a partner machine. apparatus. 4. A facsimile device having a resolution conversion means for converting the resolution of the stored image information and transmitting it to a partner machine, and a communication mode judging means for distinguishing a communication mode, and a resolution capability of the partner machine. And a resolution comparison unit that determines whether or not the transmission resolution determined based on the above and the resolution of the stored transmission image information are substantially equal, and the resolution comparison unit determines that the two resolutions are substantially equal to each other. In the above case, the facsimile apparatus is configured to determine whether or not to convert the resolution of the stored image information based on the communication mode detected by the communication mode determination means.