JPS5859665A - Picture and writing transmission device - Google Patents

Abstract

PURPOSE:To effectively utilize capacity of a receiving buffer, and to shorten a transmission time, by operating idle capacity of the receiving buffer, and forming picture and writing data for transmission if idle capacity exists. CONSTITUTION:A timer 10 takes a difference of time between an encoding start time t1 of the first scanning line, and a time t2 when picture and writing data start to be outputted from a receiving buffer 8, and output it to a divider 11. As a result, the divider 11 operates all the scanning lines of the picture and writing data outputted from the receiving buffer 8, a difference of this operation result and a counting value of a scanning line counter 12 is derived by a subtracter 13, and the obtained result is regarded as the number of picture and writing data stored at present in the receiving buffer 8. A comparator 14 compares the number of picture and writing data in the receiving buffer 8 with capacity (gamma) of the receiving buffer 8, which has been set in advance, and in case when there is room in the receiving buffer 8, an off-signal is applied to an encoder 3, and the picture and writing data is formed until the receiving buffer 8 becomes full.

Description

[Detailed Description of the Invention] The present invention relates to a calligraphy and drawing transmission device that transmits calligraphy and drawings through one communication line, and particularly relates to a calligraphy and drawing transmission device that aims to effectively utilize a buffer 1 that temporarily stores transmitted calligraphy and drawing data. .

First, a conventional document and image transmission device will be explained using FIG.

In the figure, the manuscript to be transmitted is set on the calligraphic input device L, and the manuscript is optically scanned and received! The signal is converted into a signal by an optical element or the like, and calligraphic data is formed. This drawing data is formed as a digital signal representing, for example, white or black on a pixel basis.

The calligraphy data formed by the calligraphy input device 1 is given to the -H transmission buffer 12 and temporarily stored therein.

That is, if the ``leopard'' calligraphy data that has been formed after reading the original is transmitted as it is, the data will have a large degree of redundancy and the transmission will be inefficient. Therefore, the encoder 8 installed next
Compression of encoded data is attempted, but the encoding speed of code 1g differs depending on the size of the data, and it is not always the case that the calligraphy data output from the human power system W11 is encoded in a convenient manner. Situations may occur such as when the encoder 8 is performing encoding of the previous scan line. Therefore, a buffer 2 is provided before the encoder 8 to wait for the turn.

The calligraphic data encoded by the encoder 8 is input to the modulator 4, modulated into an electrical signal suitable for transmission, and sent to the communication line 6.

The modulated calligraphy data sent to the communication line 6 is demodulated into encoded calligraphy data by the demodulator 6 on the receiving side.
The encoded calligraphy data obtained by demodulation is further decoded by a decoder 7 into a signal corresponding to the calligraphy data obtained by the calligraphy input device 1.

After the decoded calligraphy data is temporarily stored in the reception buffer 18 and waits for its turn to be recorded, it is recorded by the IllF image output device 9, and reproduced calligraphy data corresponding to the calligraphy data of the original sent from the transmitting side is obtained. .

In the conventional device configured as described above, overflow of the reception buffer 18 (data is lost due to an attempt to store more data than the capacity of the buffer 1) is a problem. Ta. That is, when the capacity of the transmission buffer 14 becomes full of calligraphy data, the scanning of the calligraphy input device 1 is temporarily stopped, and the above-mentioned overflow can be avoided by itself by suppressing the generation of data. However, the receiving buffer 8 may overflow depending on the transmission speed of the calligraphic data sent from the communication line 6. - In order to cope with such a situation, in the conventional device, the recording speed of the calligraphy output device 9, that is, the speed of the calligraphy data being output from the reception buffer 18, is communicated in advance from the receiving side to the sending side before transmitting the calligraphy data. The design is such that the sending side does not send calligraphy data at a speed higher than the informed speed.

For example, it takes time of 4C# sec/line for the calligraphy output device 9 to record one stroke of the LC line of calligraphy output, The calligraphic data to be displayed is one scanning line ha
If it is btt/sec.

->↓ If the condition continues, the reception buffer 18 will overflow because data is sent faster than it is recorded. Therefore, on the transmitting side, dummy data b bit/1ine is added to the data transmitted by the encoder 8.

(si+b) # -1111111 and decode this dummy data b bit/1ine is? The overflow of the receive buffer 8 is avoided by removing the data in the above.

In the method for avoiding overflow, dummy data is always added in the situation where ω〉〉 regardless of the capacity of the reception buffer 18.

In the end, only the capacity of the reception buffer 18 corresponding to one scanning line is used, resulting in a large waste of the reception buffer and the disadvantage that the transmission time is delayed due to the large amount of dummy data added. This drawback becomes particularly noticeable when the scanning speed of the drawing input device 1 is lower than the one-scan line recording speed of the drawing recording device 9.

Therefore, the main purpose of this invention is to make effective use of the buffer 1 that temporarily stores calligraphy and painting data.

It is an object of the present invention to provide a calligraphy and drawing transmission device which aims at shortening the transmission time of calligraphy and drawings.

The above objects and other objects and features of Jin's invention will become more apparent from the following detailed description with reference to the drawings.

To summarize this invention, on the transmitting side, the free capacity of the receiving buffer is calculated based on the elapsed time from the start of encoding, and when encoding calligraphic data, if there is free capacity from the calculation result, the receiving buffer is 1.9 By stopping the addition of dummy data in the encoder until the encoder is full and forming document and image data for transmission, the capacity of the reception fluctuation is effectively utilized and the transmission time is shortened. Figure 2 is a professional diagram of one embodiment of this invention.

In this embodiment as well, the calligraphy data obtained by the calligraphy input device 1 is sent to the transmission buffer 1!, similarly to the conventional device described above. After being stored in I!, it is encoded by an encoder and further modulated by I! On the receiving side, the calligraphic data sent via the communication line 6 is sequentially passed through a demodulator 6 and a decoder 7, and is decoded into encoded calligraphic data. In this embodiment, the following configuration is added to the above-mentioned configuration on the transmitting side.

That is, a timer 10 consisting of a counter that counts the elapsed time from the time when the encoder 3 starts encoding the first scanning line.
A scanning line counter 12b5 is provided which increases the count value each time the encoder 8 finishes encoding one scanning line. Further, a divider 11 is provided, and this divider 11 is configured to divide one of the calligraphic output devices 9 on the receiving side in advance of the transmission of the original.
A scanning line output speed (as see/11ne) is set, and the number of recording scanning lines on the receiving side is calculated by dividing the elapsed time information given from the timer 1 run. The divider 1
The number of recording scanning lines calculated in 1 and the scanning line counter 1
A subtracter 111bs given a count value of 2 is provided to perform subtraction of both input signals. The obtained subtraction result is regarded as the number of drawing data currently stored in the receiving buffer 8, and is applied to the comparator 14. In the comparator 14, the capacity of the receiving buffer 18 is set in advance as one comparison information, and a comparison is made with the number of calligraphic data stored in the receiving buffer 18 output from the subtractor 1 Sukejima. Comparator 14
7) The output is given to the encoder 8 to control whether or not dummy data should be added when encoding the drawing data.

Next, the operation of the embodiment configured as described above will be explained.

Prior to transmission of calligraphy data, the output speed of one scanning line (as sec/1i) of the calligraphy output device 9 is transmitted from the receiving side to the sending side.
fe) is notified, and at the same time the content 31 of the receive buffer 18 is
(r scanning line segments) is also notified. In the sending mode, one scanning line output speed ω is set in the divider 11, and the capacity γ of the receiving buffer 8 is set in the comparator 14.

Just like the conventional device, the manuscript is a calligraphic input device! kl and converted into calligraphy data. The writing data is encoded by an encoder 8 to reduce redundancy, and if there is a previous scanning line that is not encoded, the writing data is temporarily stored in a transmission buffer 12. The encoded calligraphic data is modulated by a modulator 4 and sent to the receiving side via one communication line 6, as in the conventional apparatus. The receiving side reproduces the received electrical signal.
It is demodulated by the II unit 6 and further decoded by the decoder to reproduce the document and image data. The reproduced calligraphy data is temporarily stored in the reception buffer 8, and outputted to the calligraphy output device 9 after waiting for its turn to obtain a reproduced image of the original.

In this embodiment, when encoder 8 starts encoding the first scan line, it starts timer 1 (Ft) to count the passage of time. Each time, the scanning line counter 12 is incremented by one.

Transmission operation-ζ Therefore, the timer 1G calculates the time from the first scanning line encoding start time t1 to the current tn (tn-t
Furthermore, the time from the first scanning line encoding start time t1 to the time t2 when this first iiF image data starts to be output from the reception buffer 18 (tffi
-tl) (This value is set to an excessive value in advance.

) and outputs the value of (tn t sec) to the divider 11. The above (tn - t2 ) sec means the time from when the receiving buffer 8 starts outputting calligraphy data to the present.

The divider 11 has already calculated one scanning line data degree ω of the drawing output device 9.
(sec/Ins) is nutted, and [tntg] is calculated from these input signals. In ω, [ ] represents a Gaussian symbol, and the calculation result of [□] executed by the divider 11 indicates the total number of scanning lines of the calligraphy data output from the receiving buffer 8.

On the other hand, the scanning line counter 12 holds the number of scanning lines of the drawing data that has been encoded up to the present time.

The subtracter 18 uses the calculation result of the divider 11 and the scanning line counter 1.
2, that is, L, [inn here]-, and the obtained result is regarded as the number of calligraphy data currently stored in the reception buffer 8. The number of drawing data is compared with the capacity of the reception buffer 8 which has already been loaded, and IIIT, and if there is room in the reception buffer 18, an off signal is sent.

When the reception buffer yll is in a state where an overflow occurs, an on signal is given to each encoder 8. When the encoder 8 receives an ON signal from the comparator 14, it adds dummy data to the scanning line data currently being encoded, and continues inserting dummy data until it receives an OFF signal from the comparator l-1. Dummy data is not added except in this state, that is, as long as there is data to be transmitted on the transmitting side and the receive buffer 1 has free space, no dummy data is added.

According to this embodiment, the receiving side informs the transmitting side of the capacity of the receiving buffer 1 and the output speed of the drawing output device in advance, and the free space of the receiving buffer 1 is determined based on the values. Since the width is calculated, it is possible to always perform appropriate data insertion even if the output speed of the receiving buffer or the output speed of the drawing output device differs depending on the receiver.

In the embodiment described above, the data value in the reception buffer 18 was calculated in units of the number of scanning lines, but by changing the count unit of the counter 1217 and the division unit of the divider 11 to bits, the capacity of the reception buffer 18 can be increased. It is also possible to operate by calculating in smaller units.

As described above, according to the present invention, the size of the free space in the receiving buffer 1 is determined by calculation on the transmitting side to control the transmission of calligraphic data, so there is no risk of overflow and insertion of dummy data is avoided. This allows the transmission time to be minimized and the transmission time to be shortened.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a conventional document and image transmission device. FIG. 2 is a block diagram of an embodiment of the present invention. In the figure, 1... Calligraphy input device, 2... Transmission parameter. 7.8...Encoder, 4-...Modulator, 6...Communication line. 6... Demodulator, 7... Decoder, 8... Reception buffer, 9... Recording device, 10... Timer, 11-
・・Divider, ・Scanning line counter, 1F・Subtractor,
14--Comparator. Agent Shin Kuzuno (1 other person)

Claims (2)

[Claims] (1) A calligraphy input device that scans a manuscript and converts the calligraphy and drawings written into electrical signals; and a transmission buffer 1 that temporarily stores the output of the calligraphy output device.
, an encoder that encodes the calligraphy data stored in the transmission buffer 1, controls the amount of data, and outputs it, and changes the encoded calligraphy data to generate a signal suitable for the communication circuit. and a demodulator that demodulates the modulated calligraphic data sent through the communication line. A decoder that reproduces calligraphy and drawing data from the demodulated electrical signal; a reception buffer 1 that temporarily stores the decoded calligraphy and drawing data; and a reception buffer 1 that reproduces calligraphy and drawings corresponding to the manuscript from the 11 times the data output from the reception buffer. Calligraphic output device. A document and image transmission device comprising: a calculation device that calculates an empty area of a buffer 1 provided on a reception tH side based on the encoding start lζ of the encoder, and provides the calculation result to the encoder. (2) The arithmetic unit is a timer that counts time at the start of encoding. A divider that calculates the amount of data derived from the receiving buffer from the output of the timer, and a counter that counts the amount of written and drawn data that has been encoded. A subtracter that calculates the amount of data in the receiving buffer 1 from the outputs of the divider and the counter, and a comparator that determines whether there is free space in the receiving buffer from the result of the subtracter. A calligraphy and drawing transmission device according to claim (1), characterized in that: