JPH08204915A - Facsimile equipment - Google Patents

Abstract

PURPOSE: To stabilize the reading stop position of an original in spite of subscanning line density and to prevent reading scanning from being stopped in the middle of the page of the original. CONSTITUTION: After the subscanning reading of image data is performed through an image reading part 2 at the speed corresponding to the highest scanning line density, encoding processing is performed corresponding to previously set reading accuracy. Further, the subscanning reading of image data is performed at the speed corresponding to the highest scanning line density until an encoded data buffer b2 is turned to a full state, and encoding processing is performed with previously set reading accuracy. The encoded data buffer b2 stores only the encoded data for one page of the original and after the image data for one page are read and scanned, the reading scanning of the next page is not started until a response comes from an opposite side machine.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a facsimile apparatus in which the reading stop position of a document is stable regardless of the sub-scanning line density of image data and reading scanning is not stopped in the middle of a page of the document.

[0002]

2. Description of the Related Art In a facsimile apparatus, a reading accuracy is selected in accordance with a sub-scanning line density (fineness of an image) of a transmission original so that image data can be read and transmitted to a partner machine (a partner facsimile machine). Has become. For reading accuracy,
There are normal, fine, super fine, etc., 1m
While m sub-scanning (paper feed of the original) is performed, scanning is performed for 3.85 lines in the normal mode, 7.7 lines in the fine mode, and 15.4 lines in the super fine mode, and the read data is encoded. I'm sending it later.

Therefore, when the characters and figures on the original are large and rough, fast transmission is possible by reading and transmitting normally, and when the characters and figures on the original are small and fine, depending on their fineness, etc. If you read and send in fine or super fine, the transmission speed will decrease, but you can transmit images with high resolution. In this way, when the original image is read and scanned according to the reading accuracy, the stepping motor is driven at a scanning speed suitable for these scannings to read the image data. Incidentally, the optimum scanning speed is 2400 PPS for normal, 1200 PPS for fine, and 600 PPS for super fine. The lower the sub-scanning line density, the higher the speed of the stepping motor.

[0004]

However, in the above-mentioned conventional facsimile apparatus, since the capacity of the buffer for storing the encoded data is small, when the encoding processing performed after the scanning of the image data is delayed, the reading is performed. The scanning is temporarily stopped (the stepping motor is stopped), and the reading scanning is not restarted until the encoding process is completed. However, the number of stops is increased and the sub-scanning line density is low (the image is rough). ), Because the scanning speed is faster,
When the reading scan is stopped with the reading accuracy with a high sub-scanning line density, the stop position of the reading scan often shifts.

The present invention has been proposed in view of the above points, and stabilizes the reading stop position of a document regardless of the sub-scanning line density, and prevents the reading scan from stopping in the middle of a page of the document. To provide a facsimile machine that
Its purpose is.

[0006]

A facsimile apparatus according to claim 1 of the present invention, which has been proposed to achieve the above object, performs sub-scanning reading of image data at a speed corresponding to the highest scanning line density. After that, the encoding process is performed according to the preset reading accuracy. Here, the reading accuracy corresponding to the scanning line density is normal, fine, super fine,
There is Hyper Fine and the like, and the scanning speed corresponding to these reading accuracy is 600 PPS to 2400 PPS. In the present invention, the scanning speed (600 PPS) at the time of hyper fine (super fine), which is the reading accuracy corresponding to the highest scanning line density, is the speed of the sub-scanning reading even at other reading accuracy.

According to another aspect of the present invention, the facsimile apparatus performs sub-scanning reading of image data at a speed corresponding to the highest scanning line density until the coded data buffer becomes full, and preset reading accuracy. The encoding process is performed with. The encoded data buffer is a buffer memory using a RAM and has a large capacity of 64 Kbytes, for example.

A facsimile apparatus according to a third aspect of the present invention includes a coded data buffer for storing image data that has been read, scanned, and coded, and the buffer stores only coded data for one page of a document. Thus, after the image data for one page is read and scanned, the reading and scanning of the next page is not started until a response is received from the partner device. Where 1
The reading scanning of the original for the page is performed at a speed corresponding to the highest sub-scanning line density, and when the transmission of the encoded data for one page is completed, the scanning for reading the next page is started.

[0009]

The facsimile apparatus according to claim 1 of the present invention having the above-mentioned construction is applied to the type of scanner transmission, and has the highest sub-scanning speed for reading and scanning regardless of reading accuracy. Adjust the speed according to the density. That is, since the sub-scanning speed is set to the slowest speed for scanning, the stop position of the reading scan does not shift due to the reading accuracy when the encoding process is delayed.

A facsimile machine according to a second aspect is applied to a type having a buffer having a relatively large capacity,
When reading scanning is performed and a predetermined line (for example, 50 lines) is accumulated in the buffer, encoding is performed and the encoded data is stored in the encoded data buffer. The sub-scanning speed is set to the speed corresponding to the highest scanning line density until the buffer becomes full (full). When the buffer becomes full, driving of the stepping motor is stopped and reading scanning is stopped. After that, when the encoded data is transmitted to the other device and the encoded data buffer becomes available, the reading scanning is restarted at the same scanning speed as before the stop. As a result, the read scan can be continued until the encoded data buffer becomes full, and the stop of the read scan in the middle of the page is reduced.

In the facsimile machine according to the third aspect,
The encoded data is stored in the encoded data buffer for each page of the document. The reading scan here is performed at a speed corresponding to the highest scanning line density at the sub-scanning speed. Do not start. When there is a response of transmission completion from the partner device, the data stored in the encoded data buffer is invalidated so that the encoded data of the next page can be stored. As a result, the full state (fullness) of the encoded data buffer due to the reading of the next page does not occur, and it is possible to prevent the reading scan from stopping in the middle of the same page.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an example of the configuration of a facsimile device F according to the present invention. In the facsimile apparatus F, a motor control unit 1 for driving and controlling a stepping motor M (main scanning motor and sub-scanning motor) used for reading and scanning and document feeding, and a document fed by the stepping motor M and the like. An image reading unit 2 for reading the image data, a print output unit 3 for printing and outputting a desired image on a recording sheet, a ten-key pad, and other operation keys, and an operation unit for performing a read accuracy setting change operation and the like. 4, a display unit 5 including a liquid crystal display, a modem for transmitting and receiving image data, a line control unit 6 for controlling switching of line connection to the communication line L, and a CPU for controlling the above units The control unit 7 is composed of the above. In the figure, b1 is a read data buffer for storing a predetermined number of lines of image data read and scanned by the image reading unit 2, and b2 is an encoded data buffer for encoding and storing the image data stored in the read data buffer b1. Note that these buffers are buffer memories using RAM.

In the scanner transmission, the read image data is not accumulated and is encoded in parallel with the read scanning and is sequentially transmitted to the other device. For reading scanning, the motor control unit 1 drives the stepping motor M,
Do this while feeding the original. The reading interval in the sub-scanning direction at this time is defined as reading accuracy corresponding to the sub-scanning line density. Normal is 3.85 lines / mm, fine is 7.75 lines / mm, and 15. Four
In the case of line / mm, it is super fine.
The optimum scanning speed corresponding to each reading accuracy is 2400 PPS for normal, 1200 PPS for fine, and 600 PPS for super fine. In the case of the present invention,
The scanning speed corresponding to the highest scanning line density is 600 PPS of Super Fine. That is, the sub-scanning speed is set to the slowest speed among the speeds corresponding to the scanning line density regardless of the reading accuracy.

The reading scanning when the sub-scanning speed is set to the speed corresponding to the highest scanning line density in this way will be described with reference to FIG. As shown in the figure, in the conventional facsimile machine, the scan line 1,
5,9, fine scan lines 1,3,5,7,9,
In Superfine, scanning lines 1 to 10 (all scanning lines) were read and scanned. In the present invention, since the scanning speed is set to a speed corresponding to super fine, the scanning lines 1 to 10 (all scanning lines) are read and scanned.

The image reading unit 2 selects only the data of the scanning line necessary for each reading accuracy and stores it in the read data buffer b1. In this way, the image data stored in the read data buffer b1 is coded by the MH, MR method or the like when a predetermined line (for example, 50 lines) is accumulated and stored in the coded data buffer b2. . That is, since the encoding process is performed only on the image data stored in the read data buffer b1, the process is the same as the conventional process even when the sub-scanning speed is low.

After that, the control unit 7 reads out the encoded data from the encoded data buffer b2 and transmits it to the partner device via the line control unit 6. In this method, since the encoding process is performed with the scanning line density according to the preset reading accuracy, it is not necessary to increase the capacity of the encoded data buffer b2 as compared with the conventional device, and the encoding process is performed. Since the data is transmitted, the transmission speed does not slow down even when the reading accuracy is normal or fine.

However, when the transmission process and the encoding process are delayed due to the failure of the communication line L and the reading of fine data such as figures, the reading scan is temporarily stopped (the stepping motor M is stopped) to synchronize. Measure When the transmission process and the encoding process are completed and the read data buffer b1 is ready for use, the read scan is restarted. In the present invention, due to such factors, the stepping motor M
When the scanning is stopped, the scanning speed is low and the scanning speed is the same at any reading accuracy, so that the scanning scanning stop position does not shift.

In the facsimile apparatus F according to the second aspect, the sub-scanning speed is set to the speed (600 PPS) corresponding to the highest scanning line density until the coded data buffer b2 becomes full (full), and the reading scanning is performed. After that, it is encoded with the reading accuracy set in advance by the operation unit 4. As a result, the capacity of the encoded data buffer b2 can be increased to, for example, 64K.
If the byte capacity is set to a large value, it is possible to reduce the possibility that the reading scan is stopped in the middle of the page.

When the encoded data buffer b2 becomes full, the driving of the stepping motor M is stopped,
Stop the reading scan. After that, when the encoded data is transmitted to the other device and the encoded data buffer b2 becomes available, the reading scanning is restarted at the same scanning speed as before the stop. In the facsimile apparatus F according to the third aspect, the scanning and the encoding process of the image data are performed for each page of the document. The reading scanning here is performed by setting the sub-scanning speed to a speed corresponding to the highest scanning line density (600 PPS), and even if the encoded data buffer b2 has a vacancy, until the response from the other device is received, Do not start scanning the next page. Here, it is necessary to set the capacity of the encoded data buffer b2 to a capacity (for example, 64 Kbytes) sufficient to store the encoded data of one page of the document.
As a result, the full state (fullness) of the encoded data buffer b2 due to the reading of the next page does not occur, and it is possible to prevent the reading scan from stopping in the middle of the same page.

After the encoded data is transmitted, when a reception completion response is received from the other device (receiver), the encoded data buffer b2
The data stored in is invalidated so that the encoded data of the next page can be stored. At this time, if the other device responds with a signal indicating a poor image quality, it is possible not to start reading the next page in order to retransmit the image data stored in the encoded data buffer b2. .

Next, the basic operation of the facsimile apparatus F of the present invention described above will be explained using a flow chart. Steps 100 to 117 in FIG. 3 show the reading and encoding processing of image data for one page.
The capacity of the coded data buffer b2 is 64 Kbytes, and when the coded data exceeds 64 Kbytes, the reading scan is stopped and the stepping motor M is stopped.

Before the reading is started, the reading interval (reading accuracy) is set by the sub-scanning line density, and the scanning speed for reading scanning is set to 600 PPS regardless of the set reading accuracy. Then, after the reading is stopped, the stepping motor M is stopped. This method, after stopping the motor pulse,
The motor excitation is stopped after a predetermined time has elapsed. In the figure, if the motor excitation stop counter is set to 10, the drive of the motor is stopped after 0.1 seconds. In addition,
By performing the motor excitation stop processing in parallel as shown in the figure, it is possible to perform parallel processing with the encoding processing.

[0023]

As can be understood from the above description, according to the facsimile apparatus of the first aspect of the present invention, the reading scan (sub-scan) is stopped when the transmission process or the encoding process is delayed. The position does not shift due to the reading accuracy, and the accuracy of the transmitted image can be maintained.

According to the second aspect of the present invention, the reading scanning is continued until the large-capacity encoded data buffer becomes full, so that the reading scanning can be prevented from being stopped in the middle of the page. Further, according to the facsimile apparatus of the third aspect, since the encoded data is stored in the encoded data buffer for each page, it is possible to completely prevent the reading scanning from being stopped in the middle of the page. Therefore, the accuracy of the transmitted image in the page can be maintained.

[Brief description of drawings]

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

FIG. 2 is a diagram for explaining reading scanning by the facsimile apparatus according to the present invention.

FIG. 3 is a flowchart showing the operation of the facsimile apparatus according to the present invention.

[Explanation of symbols]

 F ... Facsimile device M ... Stepping motor 1 ... Motor control unit 2 ... Image reading unit 4 ... Operation unit 7 ... Control unit b1 ... Read data buffer b2 ... Code Data buffer

Claims (3)

[Claims] 1. In a facsimile apparatus in which the reading accuracy of image data can be changed and which is encoded and transmitted every time the image data is read and scanned, a speed corresponding to the highest scanning line density for the sub-scanning reading of the image data. After performing the above, the facsimile apparatus is characterized by performing an encoding process according to a preset reading accuracy. 2. A facsimile apparatus having a coded data buffer in which the reading accuracy of image data can be set and changed, and which scans, scans, and stores coded image data, the coded data buffer is in a full state. Up to the above, the facsimile apparatus is characterized in that the sub-scanning reading of the image data is performed at a speed corresponding to the highest scanning line density, and the encoding processing is performed with a preset reading accuracy. 3. A coded data buffer for storing read and scanned image data, the coded data buffer comprising:
Only one page of encoded data of the original is stored, and after reading and scanning one page of image data, reading scanning of the next page is not started until there is a response from the other device. The facsimile apparatus according to claim 1.