JPS61200771A - image transmitting device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to an image transmitting device that encodes and transmits an image signal.

<Prior Art> Conventionally, a technique is known in which a document image is read, an image signal is encoded, and then transmitted electronically, thereby shortening the transmission time. Furthermore, recent advances in communication technology have made it possible to send a large amount of information in a short transmission time; for example, it is possible to send a large amount of information at 9800 brts/sea over a general public telephone line.

Therefore, situations are actually occurring in which the reading and encoding speeds cannot keep up with the transmission speeds.

Taking a facsimile machine as an example, the amount of information when encoding a line in which all - lines are white is 31 bits including the EOL signal in the case of MH code, and 15 bits including the EOL signal in the case of MR code. It is. Therefore, if this is transmitted at 9800 bits/sec, the time required for transmission will be 3,2. m5ec, 1 in IR
．． It is 5m5ec.

On the other hand, when using a charge accumulation type image sensor such as COD, the time required to read and encode the - line is
reading) time 2,7 m5ec.

The data transfer time is 2,2 m5ec, and the encoding processing time is 0,1 m5ec, resulting in a total of 5.0 m5ec.

In other words, in the case of the MH code, there is a free time of 1.8 m5ec, and in the case of the MR code, there is a free time of 3.5 m5ec. Conventionally, a dummy signal called a fill bit is transmitted during this free time, and the encoding is completed. I was waiting for it to happen.

This is particularly a problem in areas where the amount of encoded signals is small, such as the margins at the leading edge of the document, where the amount of dummy signals is extremely large, resulting in a long transmission time.

Purpose of the Invention In view of the problems of the prior art as described above, it is an object of the present invention to provide an image transmitting device that reduces the amount of dummy signals regardless of the amount of encoded signals and shortens transmission time.

<Embodiment> Hereinafter, an embodiment of a facsimile apparatus that implements the present invention will be described in detail.

(Mechanism system) In Figure 1, which shows a cross-sectional view of a facsimile machine, 41 is a COD solid-state line image sensor, 42 is an imaging lens, 43 is a mirror, 44 is a lamp for document illumination, 45 is a document feed roller, Reference numeral 46 denotes a document discharge roller, 47 a document feed tray, and 31 a document detection sensor for detecting the presence or absence of a document on the paper feed tray.

Further, 34 is a roll paper storage cover, 35 is a roll paper, and 36 is a roll paper storage cover.
37 is a paper output tray for originals and recording paper, 38 is a cutter, and 38 is a paper output tray for originals and recording paper.
is a roll paper discharge roller, 39 is a roll paper transport roller, 4
0 is a recording head, and 33 is a roll paper cover sensor that detects whether the cover 34 is opened or closed.

In the figure, when reading a document, the document on the document feed tray 47 is conveyed by rollers 45 and 46.

The document is illuminated by a lamp 44 at the reading position P, and the reflected light is imaged on the image sensor 41 via the mirror 43 and lens 42, and the image sensor 41 converts the image into an electrical signal.

On the other hand, during recording, the roll paper 35 is connected to the roller 39 and the head 40.
An image is formed on the heat-sensitive roll paper 35 by the head 40 at the same time as the heat-sensitive roll paper 35 is conveyed. When recording for one page is completed, the roll paper 35 is cut by a cutter 37 and discharged onto a paper discharge tray 36 by a roller 38.

(Basic Block) FIG. 2(A) is a basic control block diagram of the facsimile machine of this embodiment. In FIG. One embodiment includes a random access memory (hereinafter referred to as RAM) that functions as a buffer for temporarily storing the image signal, 9 a first-in-first-out RAM (hereinafter referred to as FIFORAM) that stores the encoded image signal, and 11 an MPU 23.
13 is a RAM that stores flags, data, etc. necessary for the operation of the MPU, 15 is an operation unit with input keys 2 displays, etc., 17 is a copy on thermal paper a recording unit for recording images, received images, and management data; 19 a modem for modulating transmitted data and demodulating received data; 20 a telephone;
1 is a network control unit (hereinafter referred to as NCU) which controls the connection of the communication circuit 22 to the modem 19 or telephone 20; and 23 is an MPU which controls the entire system. In this embodiment, the MPU 23 uses an Intel 8086 that can directly access a 16-bit data bus 24 and a memory space of up to 4 megabytes.

The basic functions of the MPU 23 include 6 as shown in Figure 2 (B).
There are seeds. Each function will be explained below in the context of the flow of image data.

(Transmission Operation) In this example, the flow of image data during a transmission operation will be explained using FIG. 3. This example shows an example of transmission using an MH code.

In response to a reading command from the MPU 23, the reading unit 1 converts the image data for 1 life into a run length code RL and reads it as R.
Two line buffer RAMs that store AM3 data as is.
5, alternately transfer one line at a time to RAM7, and
Run length code R read from tree line buffer
Encode L into MH code and write it to PIFORAM9.

The MPU 23 then transfers the MW code one byte at a time from the PIFORAM 9 to the modem in response to the inter-data request from the modem 19. At this time, P calculates the minimum transfer time for each line and inserts a fill bit.
One byte of data transferred from the IFORAM 9 to the modem 19 is transmitted via the NCU 21 to the receiving side via the telephone line.

Here, in the figure, reading unit 1 → RAM 3 and modem 19 → NCU
All other data transfers except for 21 are performed by MPU 23.
This is done via the bus 24.

The data request interval from the modem 19 changes depending on the transmission rate.

Data transfer is done in bytes, so 9600
For bps, 8/9600=0.83X1 (13se
An interwoven occurs every c.

Furthermore, when the data transfer from RAM3 to RAM5 and RAM7 is completed, the MPU 23 outputs a reading command to the reading section. While the MPU 23 is performing encoding processing (ENC) and interwoven processing, the reading unit 1 performs reading of the document and conversion from raw data to run length data.

(Regarding start timing of encoding and reading) Next, the flowchart of FIG. 4 and the timing of starting reading will be explained.

Execute the pre-procedure in step SPI. Pre-procedures include placing a call to the receiver and sending various digital control signals to the receiver. When the reception side completes reception preparation and receives a CFR indicating this, the transmission side sends a training signal to the modem 19 in SP3 to SP5, and sends a training signal to the modem 19.
'' and at the same time set a timer.Furthermore, at this point T1, an instruction is given to read and encode the original.The timer is used to set the time to stop the continuous sending of ``l''. Continuing to transport 'l' until the timer expires, the receiving side is set to the receiving state. During this time, reading and encoding are also executed, and the encoded image data of the leading portion of the document is stored in the PIFORAM 9. Then, at the time T2 when the timer expires, the MPU 23 stops sending data "1" to the modem 19, and
By enabling the interoperation from the modem 9 to the RAM 9, it becomes possible to read the image data stored in the RAMQ.

Therefore, at time T2, when image data FIX is sent to the receiving side from time T2, a certain amount of image data is already stored in RAMQ, so even if there is a blank space at the beginning of the document, reading and encoding can be done in time for the transmission speed. There will be no such situation.

When the transmission of one page is completed in SF3, the presence or absence of the next page is determined in SF3. If the next page is present, the process returns to SF3 and the same operation is performed. On the other hand, if there is no next page, the transmission operation is ended.

As described above, since the image is read and encoded while the training signal and "1" are being transmitted and the encoded image data is stored in the memory, the image data cannot be encoded at the beginning of transmitting one image data. This eliminates the problem of not being able to complete the transmission in time, and the amount of fill bits that are dummy signals to be sent is also reduced, making it possible to shorten the overall transmission time.

In this embodiment, reading and encoding are started after CFH is detected, but reading and encoding may be started before CFH is detected. However, if an error occurs before CFH is detected, Since the read information is often wasted, it is preferable to do so after the CFH is detected.

Effects> As explained in detail above, according to the present invention, reading and encoding will not be delayed in time for image data transmission at the initial stage of image data transmission, so the amount of dummy signals transmitted is reduced, and the overall It is possible to shorten the transmission time.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of the facsimile machine of this embodiment, FIG. 2 (A) is a control block diagram of the device in FIG. 1, and FIG. 2 (B)
is a functional block diagram of the MPU 23, FIG. 3 is a block diagram showing the flow of image data during transmission, FIG. 4 is a control flowchart, and FIG. 5 is a timing diagram.

Claims (1)

[Claims] a reading means that reads the original image and converts it into an image signal;
Encoding means for compressing and encoding the image signal, storage means for temporarily storing the encoded image signal encoded by the encoding means, sending out the encoded image signal in the storage means,
Signal sending means for sending out a setting signal for setting the communicating party to a receiving state before sending out the encoded image signal, and control for starting the operations of the reading means and the encoding means while sending the setting signal. An image transmitting device characterized by having a means.