JPS592482A - Facsimile transmission system - Google Patents

Abstract

PURPOSE:To attain the switching to a different mode without change in the protocol procedure, by transmitting a part of a mode set signal together with a specific area in a picture transmission signal inclusive, in the transmission mode set system using the protocol procedure. CONSTITUTION:An SK informing signal is inserted to a section tSKP at the transmission side every time a picture reading scanning section 1 detects a white line in the skip SK mode A set with the protocol procedure, and the line transmission period is brought to T'. A CPU4a discriminates whether or not the scanning line is the write line to be SK-processing depending whether or not the number of bits of the black part included in the scanning line reaches a prescribed number, and when the line is the SK line, data of synchronizing signal sections tSY and tSKP is added and transmitted. The transmission of data to an information storage section 10 is not done when the CPU4a detects the tSKP succeeding to the section tSY at the receiving side, a signal is given to a step motor 11 only and the line skip three times the normal frequency is done. In case of the SK mode B, a tSKPB is added to a period succeeding to the section tSKP to make the scanning line density of the SK line coarse.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mode signal transmission method in a facsimile machine that is equipped with a scanning line density switching function, a line skip function, etc., and is capable of operating by selecting one of a plurality of different transmission modes. .

In analog transmission facsimile machines, which directly transmit image information read from a document without compressing it through encoding or other means, the scanning line density can be switched coarsely or finely as necessary to shorten transmission time. There is also known a system that can switch to a so-called line skip method, in which parts of a document with low information density are skipped. For example, C
In the facsimile according to the Gll standard by CI'r T, the scanning frequency i1 is 6Hz (360 rpm) and the scanning line density is 3.851/m. There are known facsimile systemists who became capable of operating a facsimile system out of desperation.

■ 3 minute mode (3,8517am, 6 Hz)
■ 2 minute mode (2,57t 7m, 6Hz)
■ Skip A-e-do (3,851/lry, 18
/6Hz) ■ Skip B mode (2,57t/m,
18/6l-1z) -In addition, in modes ■ and ■, when 1247 minutes of image information is determined to be all white due to the white part of the original, the scanning frequency f of this line is changed to the scanning frequency f' of l8Hz. This is a mode in which the transmission time is three times that of the steady state, and the transmission time is short.

By the way, in a system that can operate by arbitrarily switching to one of the different modes, it goes without saying that the switching must be done with the transmitting and receiving sides in agreement with the selected mode. Must be.

Conventionally, methods based on protocol procedures have been widely used for such cooperation between the transmitting side and the receiving side.

Figure 1 shows the tonal (t
-91Jt of the protocol by onal) signal is shown.

In the figure, TX indicates the signal transmission timing from the transmitting side for each mode, and RX indicates the signal transmission timing from the receiving side.

After setting up the line, the receiving side RX sends a CED (Cold Φ Station Identification) signal with frequency f, and when the operator presses the start button in response, the sending side 1゛X transmits the frequency f. C of fa
'NG (calling tone) receiving side RX has frequency f,
At this time, the receiver (i side 1 (X is the 4
If the system is capable of operating in modes ① to ②, a 5UBGI signal of frequency f is added after the GI multiplied signal.

If the 5UBGI signal is added to the GI (g), the transmitting side T The signal is sent according to any one of the tonal modes 1 to 1 corresponding to one mode, and if the mode has been selected, the GCI (group command l) signal of frequency f, and the frequency f, L
C8 (line conditioning fist signal) signal'
t[, and the receiving side RX thereby knows that mode ■ has been selected, and correspondingly sets the operating mode to ■.

After that, the transmitting side TX sends PH8 (phase matching signal), and when the receiving side pillow
ESSAG), and in response, the receiving side RX
Now we begin recording image information.

In the same shuttle, when mode ■ is selected, the frequency f
Following the GCI signal of , a GC2 signal of frequency f is sent, and when mode ■ is set, GC8 of frequency f is sent.
KPI (Group Command Skip L) signal and L
A CS signal is sent out, and when mode (2) is selected, a GC8KPI signal and a GC8KP2 signal of frequency f are sent out, and the receiving side RX sets the operation of each mode accordingly.

In this way, in the past, all switching to multiple modes was done using a protocol procedure using tonal signals, so as the number of selectable modes increases, the types of tonal signals increase, and the number of detectors for this increases. Not only will the scenery become more scenic, but the protocol procedures will become more complex.

Therefore, in conventional systems, if there are many selectable modes, the protocol configuration becomes complicated, which tends to increase costs, and the number of tonal signals to be detected increases, resulting in false detection and other problems. This method has disadvantages in that malfunctions due to interference from other devices increase, and the time required for the protocol increases, which tends to increase transmission costs.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a facsimile transmission system that eliminates the drawbacks of the prior art described above and allows switching between the transmitting and receiving sides to different modes without changing the contents of the front call I11.

In order to achieve this object, the present invention is characterized in that a mode identification signal is included in a specific area of the image information transmission after the protocol is transmitted.

Embodiments of the facsimile transmission system according to the present invention will be described below with reference to the drawings.

FIG. 2 is a simple example of a computer-controlled facsimile device which is adapted to apply the present invention and can operate in any of the four modes described above, Modes ■ and Mode ■. Part 9, 2 is a stepping motor for sub-scanning drive, 3 is S/P (direct parallel converter), 4 is a microcomputer control unit, and 5 is P/P.
S (parallel-serial converter), 6 is modem, 7 is NCU
(line control device), 8 is an S/P, 9 is a P/S, 10 is an image information recording section, and 11 is a stepping motor for sub-scanning drive. Note that 4a is the CPU of the microcomputer.
(Central processing unit #1t) 4b is the same (ftOM (read only memory), 4c is the same (RAM (random access memory), 4di is the same clock generator, 6
A is a modulation section of the modem, and 6b is a demodulation section.

Next, the operation will be explained.

1. When the mode is selected.

At this time, the mode of the protocol procedure of FIG. 3 is executed, and both the transmitting side TX and receiving side RX are shown in the mode.

Therefore, the image information read from the original by the reading unit 1 on the sending side 'I''
L B is converted into bit parallel data and is provided in a fixed area B1 of RAM 4C by CPU 4a.
11114th order in F (line buffer memory),
You can store one food line at a time. In this example, 3.
Since the scanning line density is 85t/mm, the scanning depth due to the stepping motor 2 is 0. l
3 myr, therefore, CPU4a is 0.1
The image information is read at a scan line interval of 3 mm, and the RAM 4 C
GD L B F K save. Then, while reading the next 0.13 picture jlW information, it performs logical processing with the previously stored picture 1W information of the previous scanning line, and again the same -LBF
Store in.

In this way, when one line of data with a scanning line density of 3.85t/mm obtained by logical processing from the image information of two lines taken at a scanning interval of 0.13mm is stored in the LBF, Data transmission begins.

Data is sent from the LBF to the modulation section 6a of the modem 6 by converting 8-bit parallel data into υ serial data using P/85 using the CPU 4a.
It is done. Therefore, the P/S 5 serially sends data to the modulating section 6a in synchronization with a transmission bit decomposition clock (TMIJMCK) that determines whether to decompose all 1247 worth of data into bits. Then, the P/S 5 generates an IN'l'Ml)M output to the modulator 6a every time it completes transmitting 8 bits of data, instructing it to read the next 8 bits of data, and the CPU 4a IN
'r M D Receive M D M output by interrupt processing, read the next 8 bits of data from L13F and send it to P/S5, and return data from pL and BF to GD. Send it to the line from NCU7.

Next, when data is received from the line via the NCU 7, the serial data from the demodulator 6b of the modem 6 is input to the S/P 8 in synchronization with the reception bit decomposition clock (RMDMCK), and the register is set to 8 bits. When the data is filled, an INTMDM output is sent to the CPU 4a, instructing the CPU 4a to receive the data. Therefore, C
The PU 4a writes the data from the S/P 8 to the LBF by interrupt processing, and by repeating this process, the data received from the line is stored in the LBF.

In this way, when one pledge of 1247 minutes of data to LBF is completed, CPU 4 a id: P
/S9 to the image information recording unit 1 to send the data from LHF.
Output to 0. Then, every time 1247 minutes of recording is completed, a signal is sent from the CPU 4a to the stepping motor 11, and a sub-scanning feed of 0.26+nm is performed.

In this embodiment, the sub-scan feed of 0.13 is performed twice and the same data is recorded each time, so-called double-scanning recording is performed.

Therefore, at this time, one line of data is read and recorded every two sub-scanning feeds of 0.13 mm, so the scanning line interval is (0,13X2=0.26), which is 3.851 This results in operation with a scanning line density of /w.

2. When mode ■ is selected At this time, the protocol procedure in FIG.

Therefore, on the transmitting side TX, the sub-scanning feed of 0.13 mm is
After cycling and storing image information for one line in LBF,
The CPU 5a sends a signal to the stepping motor 2 to move only the document by 0.13 mm without reading the image information, and then prepare for reading the next scanning line.Furthermore, on the receiving side RX, 1247 minutes of image information 0, 13
After writing twice at a scanning line interval of mm, the CPU 4a sends the stepping motor IIK signal to feed the recording paper by an additional 0.13 tnm, and then prepares for recording the next line, in the same way as the transmitting side TX. Note that the other operations are the same as in mode (3).

Therefore, in this mode (2), image information for one line is read and recorded every time sub-scanning of 0.13× is performed three times.
3=0.39”) Ball scanning line spacing, that is 2.57t
Operation at scan line densities in the order of / is obtained.

3. When mode ■ is selected, the protocol procedure is executed as shown in Figure 3, which causes the receiver RX to select mode ■ and mode ■.
It is set to a mode that can be operated in any of the following ways.

Now, since the transmitting side TX is set to mode ■,
．． A white line skip operation is performed at a scanning line density of 85z/home.

FIG. 4 shows a transmission waveform during such a white line skip operation.

In Fig. 4, T=l/f: line transmission period T' in steady state
= l / f': skipped line transmission period to two-phase (synchronization) signal section t, : skip notification signal section, and on the transmitting side TX, every time the reading scanning unit detects a white line, the period ' A skip notification symbol indicated by ■ is inserted into skpν, and the transmission period of the line in which this skip notification signal ■ is inserted is set to T'. During this time, sub-scanning is carried out normally in preparation for reading the next line.

For this reason, the CPU 4a of the transmitting side TX logically processes the image information for two scanning lines that are read one after another by the reading unit 1 every sub-scanning feed of O, l 3 ys*.
In addition to obtaining image information for a line, in the process of performing this logical processing, check the image information for one scanning line, and check whether the number of bits in the black part included in that scanning line has reached a predetermined number per line. Depending on whether the scanning line is a line to be skipped or a white line to be skipped, it is determined whether the scanning line is a line to be skipped or a blank line.

Furthermore, the 1247 minutes of data obtained through the above logical processing is R.
It is stored in the LBF provided in a predetermined area of AM4C, but at this time, the area 18. shown in FIG. and'skp
Data (represented as [F] in the figure) is added.

In this way, 1247 minutes of data by logical processing is LBF
When the line is stored in the white line and a determination result is issued as to whether or not it is a white line, data transmission to the modem 6 starts,
Based on the above judgment, if the 1247 minutes of data is not a white line, the CPU 4a determines that the data read from the LBF is the data to be transmitted as is, but if it is a white line, the data from the LBF is Instead of reading, data which is stored in the ROM 4b or RAM 4c in advance and corresponds to the signal during the period T' in FIG. 4 is read out and sent out. Note that when that line is a white line, data for one line of LBF is converted to the above R.
The data stored in OM or RAM may be replaced with certain data, and the data to be sent may be always read from the LBF.

Thereafter, data is sent from the LBF to the modulation section 6a of the modem 6, but as already explained,
8-bit parallel data is sent to P/S5 by CPU4a.
This is done by converting the data into serial data. That is, the transmission pit decomposition clock (T
The data is serially sent to the modulating section 6a in synchronization with MDMCK). And P/S5 is the modulation section 6
When the 8-bit data transmission to a is completed, I
Generates the NTMDM output and instructs to read the next 8 bits of data, and the CPU 4a receives this ■NTMI)M output through interrupt processing, reads the next 8 bits of data from the LBF, and outputs the P/M output. 85, and by repeating this, the data from L 13 F is sent from the NCU 7 to the line. Also, when a white line appears, data is read from the ROM or RAM instead of reading from the LBF.
The data stored in is retrieved and the data shown in period 'V in FIG. 4 is sent in the same manner, but at this time,
When using the above-mentioned LBF data replacement method,
Needless to say, it is always sufficient to read from the LBF.

On the other hand, since the receiving side RX is set to the evening ■ mode, it monitors the remaining period following the interval tsy of the received data, and only the interval 'skp is at level 1L# as shown by ■. When this is detected, only the recording paper is fed and preparations are made for recording the next line.

Therefore, on the receiving side IT monitor the period following and there skip instruction signal (
iAT, period of 4 figures (dl rfl/niRgelt ■
IHkp) is detected, IL A M 4 C's
rV Set a skip occurrence flag in the skip occurrence (white line generation) memory pit S K P CN 'l' which is set in the K area, and at the same time synchronize for the four rules for the other lines following the period T'. Adjustments can be made by, for example, changing the LBF address.

Then, when the 4-input of one line of data to the LFB is completed, recording is performed by writing twice in the recording unit 10 as described above.
At this time, the CPU 4a sets the skip occurrence flag = tX, and if it is set, the image information recording unit 10
No data is sent to the stepping motor 11, and only the sub-scanning feed of 0.13+u+ is performed twice to perform a line skip of 0.26 m.

Therefore, in this case, the operation is in skip A mode, and the transmission time in the white line portion is 1/3, so the transmission speed increases in the case of a document with many line-shaped white portions parallel to the scanning direction. , high-speed transmission can be performed without significantly reducing resolution.

4. When mode ■ is selected, the transmitting side 'rX is also set to mode ■.In this mode, the transmitting side TX performs 92 times of sub-scanning in the order of 0.13 to scan one line's worth of images. Obtained by logically processing information,
After storing the LFBK, the CPU 4a sends a signal to the stepping motor 2 to perform only one sub-scanning feed of 0.13 mm without reading the image information.

Also, at this time, the same line skip operation as when mode ① was selected is performed, and when it is determined that it is a white line, a signal corresponding to period T' in Fig. 5 is sent out as data. In the data of the period T' of ^, the part indicated by ■ is added to the section tskp'a following the section 'skp' in the fifth time.

The remaining period is monitored, and if the interval tskp' becomes lWl as shown by ■, the white line skip operation is performed in the same way as in the above mode ■, and following this ■, the interval tskpm becomes lWl as shown by ■. When it is IL@, skip B which is set in WK area of RAM4C
Set the skip B mode flag in the mode generation memory bit. Note that this memo and rebit are not reset until the end of transmission for one screen.

Therefore, the CPU 4 a of the receiving side RX executes this skip B.
When the mode flag is set, the stepping motor 11 is operated three times when recording data for i, 1547 minutes, and sub-scanning feed of 0.13 mm is performed three times.

As a result, when the received data is not a white line, but is a signal of period T in FIG. 5, 0.
After writing twice with a 13mm scanning line, one more time.
The sub-scanning is performed by Q times and 13 B times, and when it is the white line data, that is, the signal of period 'r' in FIG.
Only the sub-scanning feed of 13 mm is performed three times, and the reading and recording of image information becomes equivalent to a scanning line interval of 0°39 mm, which is the original scanning line density of 2.57 L/mu. Line skip operation and ridge mode ■ operation can be obtained.

Therefore, according to this embodiment, facsimile transmission can be performed in four types of modes by using three types of protocol procedures (■, ■, (■) as shown in FIG. 3, and the number of tonal signals can be reduced. be able to.

By the way, in the above embodiment, even when mode 2 is selected, until a white line appears in the image information read from the original to be transmitted, the reception (i side RX is 3.85t/
It operates in the same mode as the scanning line density of the screen mode ■, and the receiving side RX starts when the white line is visible.
However, since normal manuscripts usually have margins around the paper, white lines often appear immediately after transmission starts, so this is almost always a problem in practice. There isn't.

In addition, if you want to complete U, you may do as follows.

That is, when mode ■ is selected, the first data sent from the transmitting side is set as skip data regardless of the data read from the original, and the receiving side is also set to mode ■ immediately after data transmission starts. It is. In this way, even in the worst case, mode 2 can be set with only one line of data loss, and mode delay can be minimized.

In addition, if the receiving side is set to have a scanning line density of 2.571/yH in @Modzu, if mode ■ is selected, the first line of data is set as skip data. good.

Further, the above is an example for explaining the present invention,
It goes without saying that the present invention is not limited to this, and can be implemented with any number of modes and mode contents.

As explained above, according to the present invention, it is possible to easily coordinate between the transmitting side and the receiving side in many types of modes without complicating the types of tonal signals or the protocol procedures. However, it is possible to provide a facsimile transmission system at low cost that can perform a reliable protocol in a short time and operate in multiple modes.

[Brief explanation of the drawing]

Fig. 1 is a timing chart showing a conventional example of a protocol using tonal signals having four types of modes, Fig. 2 is a block diagram showing an embodiment of a facsimile transmission system according to the present invention, and Fig. 3 is an example of the protocol procedure. FIGS. 4 and 5 are timing charts for explaining the operation. 1... Image information reading υ section, 2... Stepping motor for sub-scanning feed of the reading section, 3, 8...
...S/P (serial-parallel converter), 4...
...Control section, 5.9...P/8 (parallel-
Serial i replacement, 6...modem, 7...
- NCU (line control unit), 10...Reception recording section, 11...Stepping motor for recording section sub-scanning. Procedural amendment (voluntary) September 11, 1981 Patent V 110 SL No. 6 2, Title of invention 7 Axielectric transmission system 3, Relationship with the person making the amendment Patent applicant name (781M ) Patent Attorney Takeshi Junji Department 5 ]] of the order for amendment Voluntary amendment 6, Number of inventions increased by amendment None 7, Subject of amendment (1) Changed “5th” in line 1 of page 18 of the specification to “5th” 5
Corrected to ``Figure''. Q) Similarly, “W” and “L” on page 18, line 7
Correct. (3) Figures 4 and 5 of the drawings are corrected as shown in the attached corrected drawings. 9 List of attached documents

Claims (1)

[Claims] (Re) In a facsimile transmission system in which the transmission mode is set using a protocol procedure, a part of the mode setting signal is included in a specific area of the image information transmission signal and transmitted. (2) The facsimile transmission method according to claim 1, wherein the specific area is an area included in a line skip notification signal.