JPS63194466A - Video conference device - Google Patents

Abstract

PURPOSE:To transmit a plotted picture such as a drawing or a memorandum to a remote device and to obtain a hard copy by converting hand written picture information to an electric signal, transmitting through a transmission line and outputting by the use of a printer device. CONSTITUTION:The attendance of a conference plots a picture on a tablet T1 or T3 with a pen or the like, and then, the tablet T1 or T3 outputs the digital picture signal of the plotted picture to a video signal processing part 4. The video signal processing part 4 transmits the digital picture signal of the plotted picture to the remote television conference device through the transmission part 3a of a mode switching device 3, a modulator and demodulator 10, a BPF 6, a hybrid circuit 7 and a telephone line 9. The remote device outputs the signal to the video signal processing part 4 through the hybrid circuit 7, the BPF 6, the modulator and demodulator 10 and the receiving part 3b of the mode switching device 3. When a switching switch 38 is switched to a (b) side, the received digital picture signal is outputted to the printer P and the hard copy of the plotted picture os said signal can be obtained.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a video conference device.

[Prior Art] Conventionally, there has been a video conference device that can conduct a conference by bidirectionally transmitting video signals of conference attendees and their backgrounds, etc., and audio signals of the conference attendees between remote locations using telephone lines. is being developed.

[Problems to be Solved by the Invention] - In this conventional video conferencing device, for example, when a meeting attendee wants to transmit a drawn image of a drawing of meeting materials or a memo to the other party, the drawn image is transmitted to the video camera. I will show it to you. At this time, the video signal of the drawn image is transmitted to the other party's television conference device, and the drawn image is displayed on the other party's monitor television, but it is not possible to make a hard copy of the drawn image.

An object of the present invention is to solve the above-mentioned problems, to enable video conferences to be held between remote locations at all times, and to simultaneously transmit audio signals of the conference participants and to transmit drawings or memos or other drawn images to the other party. An object of the present invention is to provide a video conference device capable of transmitting data to a side device and making a hard copy.

[Means for Solving the Problems] The present invention provides an image processing system that converts handwritten image information into electrical signal image data in a video conference device equipped with means for transmitting image signals and audio signals via a transmission line. data generation means, full-duplex modem means for modulating the output of the image data generation means and outputting it to the transmission line, and demodulating the modulated image data input via the transmission line at the same time; The present invention is characterized by comprising a printer device that outputs demodulated image data output from the dual type modulation/demodulation means.

[Operation] By connecting the video conference device configured as described above via a transmission line, the image data generation means converts handwritten image information into image data of an electric signal, and then the full-duplex modulation/demodulation means modulates the output of the image data generating means and outputs it to the transmission line. In response to this, the full-duplex modem means of the other party's video conference device demodulates the modulated image data manually inputted via the transmission line, and then the printer device transmits the modulated image data from the full-duplex modem means The output demodulated image data is output in the form of a hard copy. The image data is transmitted simultaneously and bidirectionally between the two video conference devices.

[Embodiment] FIG. 1 is a block diagram of a video conference device that is an embodiment of the present invention. This television conference device is connected to a television conference device having the same configuration via a telephone line 9, and includes a video camera VC1 and a monitor television MT.

transmitting video and audio signals of conference participants to the other party's device using microphones Ml to M3 and speakers SP;
In addition to being able to conduct conventional video conferences, it is also possible to create drawings such as drawings or memos using tablets TI to T3, or to create drawings drawn using light pens to V on screen board SB. and send the above drawn image to the other party's printer P or screen board SB.
It is characterized by being able to output to.

In FIG. 1, an image signal photographed by a video camera VC is temporarily stored in a transmission image memory 1, which is a buffer memory, and then converted into a digital image signal in a high-speed mode with a transmission rate of 960 Obps to a transmission section 3 of a mode switch 3.
input to a. On the other hand, a high-speed mode digital video signal with a transmission rate of 9600 bps output from the transmitter 3b of the mode switch 3 is temporarily stored in the received image memory 2 and then output to the monitor television MT.

A tablet T1 to T3 and a microphone M1 to M3 are placed in the hands of each conference attendee, and when the conference attendee traces the tablet TI to T3 with a predetermined pen or the like, the tablet TI to T3 digitizes the drawn image. It is converted into an image signal and output to the drawing memory 32 via the changeover switch 31. After the digital image signal is temporarily stored in the drawing memory 32, it is output to the pattern synthesizer 34 and the transmission image memory 33. Further, the voices of the conference participants inputted into the microphones Ml to M3 are converted into audio signals and outputted to the detection controller 41 of the audio signal processing section 5, respectively.

A conference attendee positions the light pen W at a predetermined position on the screen of the screen board SB composed of a CRT display, and presses a switch (not shown) on the light pen W to turn it on. W is an auxiliary position memory that detects the bright line beam emitted from the screen of the screen board SH to detect position information on the screen board SB, and temporarily stores the position information of the light pen W that moves at high speed. 35 to the light pen image memory 36. In response, the light pen image memory 36 generates a digital image signal based on the input position information and outputs it to the pattern synthesizer 34 and the transmission image memory 33. The digital image signal input to the transmission image memory 33 and temporarily stored is transmitted at a transmission speed of 1
The signal is output to the transmitter 3a of the mode switch 3 as a low-speed digital image signal of 200 bps.

On the other hand, a low-speed digital image signal with a transmission rate of 1200 bps outputted from the receiving section 3b of the mode switching device 3 is once stored in the received image memory 37, which is a buffer memory of the video signal processing section 4, and then sent to the pattern synthesizer 34. Output. Butter〉・Synthesizer 34 receives image memory 37
After synthesizing the digital image signal input from the light pen image memory 36 and the digital image signal input from the drawing memory 32 on one predetermined screen, the synthesized digital image signal is transferred to the switch a of the selector switch 38. output to the scanner 33 via the side, and the changeover switch 3
It outputs to the printer P via the b side of 8. scanner 39
Based on the input digital image signal, sends the digital image signal for the field to the screen board SB.
Output to.

The mode switch 3 switches the connection mode of the digital image signal output to the full-duplex modem 10 by switching a mode switch (not shown). That is, when the mode selector switch is switched to the high-speed mode, the mode selector 3 switches and controls the transmission speed mode of the full-duplex modem 10 to the high-speed mode of 9600 bps, and at the same time controls the transmission speed of the full-duplex modem 10 to the high-speed mode of 9600 bps. The digital image signal is outputted to the signal input terminal 10a of the modulator/demodulator IO, while the digital image signal inputted from the signal output terminal 10b of the modulator/demodulator 10 is outputted to the received image memory 2. Also, when the mode selector switch is switched to low speed mode, the mode selector 3
is the transmission speed mode of the full-duplex modem 10 l 2
At the same time, the digital image signal input from the transmission image memory 33 of the video signal processing section 4 is output to the signal input terminal 10a of the modem IO, while the signal output of the modem 10 is controlled to switch to the low speed mode of 00 bps. Terminal 1
The digital image signal input from 0b is output to the received image memory 37 of the video signal processing section 4.

The full-duplex modem IO performs PSK modulation on a carrier wave signal with a carrier frequency of 1800IIz using a digital image signal input from the transmitter 3a of the mode switch 3 to the signal input terminal 10a, and outputs the PSK modulated wave to the modulation signal input/output terminal. The signal is output to the other party's video conference device via a 10C1 band pass filter (hereinafter referred to as BPF) 6, a hybrid circuit 7, and a telephone line 9. Moreover, the modem 10 connects the telephone line 9, the hybrid circuit 7, and the BE
The PSK modulated wave input via F6 and the modulated signal input/output terminal 10c is demodulated and output to the receiving section 3b of the mode switch 3 via the signal output terminal lOb.

The configuration of this full-duplex modem IO will be described in detail later. Note that the BEF 6 is a filter that extracts only the image signal input and output from the modulator/demodulator IO, while the band elimination filter (hereinafter referred to as BEF) 8 removes the image signal and extracts the human output from the audio signal processing section 5. This is a filter that extracts only the audio signal that is transmitted.

The detection controller 41 of the audio signal processing section 5 detects the level of the audio signal input manually from the microphones Ml to M2, and selects the audio signal with the highest level among the audio signals input from the three microphones Ml to M3 to the amplifier. The changeover switch 42 is switched so that the signal is output to the signal direction selector 44 via the signal direction selector 43. The signal direction switch 44 detects the levels of the audio signal manually input from the BEF 8 and the audio signal input from the amplifier 43, and outputs the audio signal with a higher input level in a predetermined direction. That is, when the level of the audio signal input from the BEF 8 is higher than the level of the audio signal input from the amplifier 43, the audio signal input from the BEF 8 is output to the speaker SP via the amplifier 45, and on the other hand, The level of the audio signal input from the amplifier 43 is BEr
If the level is higher than that of the audio signal input from the amplifier 43, the audio signal input from the amplifier 43 is outputted to the other party's video conference device via the BEF 8, the hybrid circuit 7, and the telephone line 9.

FIG. 2 is a block diagram of the full-duplex modem IO of FIG. 1. The digital image signal input to the signal input terminal 10a of the modem 10 is input to the synchronization input section 19 of the full-duplex modem lO, and at the synchronization input section 19, the input digital image signal is input from the modem side. The signal is input to the full-duplex modem lO in accordance with the synchronization signal. After the synchronized digital image signal is scrambled using a predetermined generating polynomial in the scrambler 20,
The PSK modulator 21 has a carrier frequency 1s o (l H2
PSK modulates the carrier wave with a digital image signal. P.S.
The K-modulated digital image signal has the above-mentioned carrier frequency 1.
A predetermined band centered around 800Hz (approximately 1200Hz in high-speed mode, approximately 150Hz in low-speed mode)
After unnecessary band components are removed in the digital filter 22 that extracts only
The signal is output to a D/A converter 23 (hereinafter referred to as a D/A converter) and a pseudo echo generator I5. The pseudo-echo generator 15 sets the impulse response characteristic of the transfer function as the tap coefficient of the generator 15 so that it has a characteristic equivalent to the transfer function of the path through which the echo passes, and performs convolution integration with the input signal. , and output to the differential amplifier 1514 as a pseudo echo signal. Thereby, the tap coefficients are controlled so that the echo at the output of the differential amplifier 14 is minimized. On the other hand, the D/A converter 23 performs D/A conversion on the input digital image signal and outputs the digital signal via the hybrid circuit 11 to the modulation signal input/output terminal 10c.

The hybrid circuit 11 is an image signal synthesis/separation circuit that outputs the image signal input from the modulation signal input terminal 10c only to the analog filter 12, and also outputs the image signal input from the modulation signal input terminal 10c to the analog filter 12.
The image signal manually inputted from the converter 23 is outputted only to the BPF 6. However, in reality, there will be a wrap-around from the D/A converter 23 to the analog filter 12 via the hybrid circuit ll, and a reflected wave that is turned back at the 2-wire to 4-wire conversion point in the middle of the line, so these should be avoided. A pseudo echo generator 15 is used for cancellation. The image modulation signal input to the analog filter 12 is subjected to Δ/D conversion in an analog-to-digital converter (hereinafter referred to as A/D converter) 13 after unnecessary band components such as noise are removed. The signal is input to the first input terminal of the dynamic amplifier 14. On the other hand, the pseudo echo signal output from the pseudo echo generator 15 is input to the second input terminal of the differential amplifier t4.

The differential amplifier 14 takes the difference between the two input signals, and calculates the difference between the two input signals, and calculates the difference between the two input signals and calculates the D/
The image modulation signal component that goes around from the A converter 23 to the analog filter 12 via the hybrid circuit 11, as well as the reflected wave that is turned back at the 2-wire to 4-wire conversion point in the middle of the line, is canceled by the pseudo echo signal. After amplifying the differential voltage, it is output to the PSK demodulator 16. PSK demodulator 16
The digital image modulation signal input to the carrier frequency! 8
After PSK demodulation with 00I-1z, the signal is manually input to the descrambler 18 via the line automatic equalizer I7 that compensates for the band characteristics in the telephone line 9, and a descrambling operation based on a predetermined generating polynomial is performed. descrambler 18
The digital image signal output from the signal output terminal 1
Output to 0b.

Although not shown in FIG. 2, the mode switching control signal manually inputted from the mode switching device 3 is transmitted to the analog filter 12 of the modem/demodulator 10 and the pseudo echo generator 1.
5, PSK demodulator 16, line automatic equalizer 17, descrambler 18, synchronization manual section 19, scrambler 20, PS
The control signal is input to the K inverter 21 and the digital filter 22, and each circuit has a transmission speed of 9600 bp.
s high speed mode or 1200 bps low speed mode.

The operation and operation method when two teleconference devices configured as described above are connected via the telephone line 9 will be described.

The audio signals of the conference participants inputted into the microphones Ml to M3 are output to the other party's video conference device via the audio signal processing unit 5, BEP 8, hybrid 7, and telephone line 9, and are further output to the other party's device. Hybrid circuit 7, BE
r; '8, the signal is output to the speaker SP via the audio signal processing section 5. Now, when the mode selector switch of the mode selector 3 is switched to the high-speed mode, the modem 10 operates in the high-speed mode with a transmission rate of 9600 bps. At this time, a video signal of the conference attendees and their background photographed by the video camera VC is sent to the other party via the transmission image memory l, the transmission section 3a of the mode switch 3, the modem 101BPF6, the hybrid circuit 7, and the telephone line 9. It is output to the video conference device at the other end, and is further output to the monitor television MT via the hybrid circuit 7, BPF 6, modem lO, receiving section 3b of the mode switch 3, and received image memory 2 of the device at the other end. .

Furthermore, when the mode selector switch of the mode selector 3 is switched to the low speed mode, the modem 10 is set to a transmission rate of 1200.
It operates in low speed mode of bps. At this time, when a meeting attendee draws on the tablet TI to T3 with a pen or the like, the tablet TI to T3 outputs a digital image signal of the drawn image to the video signal processing section 4. Further, when a conference attendee draws on the screen board SB using a light pen W, the drawn image is converted into a digital image signal and output to the video signal processing section 4. The video signal processing unit 4 transmits the digital image signals of the two drawn images to the transmission unit 3a1 of the mode switch 3, the modem converter 10, and the mode switch 3.
It is transmitted to the other party's video conference device via the PF 6, hybrid circuit 7 and telephone line 9, and is further transmitted to the other party's video conference device through the hybrid circuit 7, BPF 6, modem 10. The signal is output to the video signal processing section 4 via the receiving section 3b of the mode switching device 3.

Here, when the changeover switch 38 is switched to the a side, the received digital image signal is output to the screen board SB, and a drawn image of the signal is displayed. Further, when the changeover switch 38 is switched to the b side, the received digital image signal is output to the printer P, and a hard copy of the image drawn by the signal can be made. This hard copy is handed over to a particular conference attendee by a conference attendee or operator seated near the printer P. Furthermore, by correcting the image displayed on the screen board SB using the light pen W, the corrected drawn image is transmitted to the other party's video conference device in the same manner as described above, and the image displayed on the screen board SB is transmitted to the other party's screen board SB. It can also be displayed on the SB.

In the above embodiment, a drawn image drawn using a light pen W on the screen board SB is directly converted into a digital image signal, transmitted to the other party's device, and then displayed on the screen board SB or output to the printer P. Therefore, the drawing information can be displayed or output more clearly than when the drawing information is photographed and transmitted using a video camera VC.

In the above embodiment, the low-speed mode image signal generated and output by the video processing unit 4 is 1800Hz in the frequency band of the telephone line 9 (0 to 3.4Ki(z)).
occupies the +150Hz band, while the audio signal processing section 5
Although the audio signal output from the telephone line 9 includes components in the entire frequency band of the telephone line 9, the components of the audio signal in the band occupied by the image signal are removed by the BEF 8.
The audio signal and the low-speed mode image signal are frequency division multiplexed on the telephone line 9, so that the audio signal and the image signal can be simultaneously transmitted on one telephone line 9.

Here, a part of the '' component of the audio signal corresponding to the occupied band of the low-speed 2-mode image signal is removed, but since the removal band is an extremely narrow band (i), it is practically impossible to hear the audio signal. Signal clarity is not degraded.

Furthermore, since the carrier frequency of the PSK image signal is 1800 Hz, the center frequency of the second harmonic of the PSK image signal is 36001 (z, and the second harmonic of the PSK image signal exists outside the band of the telephone line 9. Therefore, 1) SKl
i! The second harmonic of the J-image signal does not affect the audio signal.

As explained above, in this video conference device, video signals and audio signals of conference attendees are transmitted to the other party's device using a video camera C1 monitor television MT, microphones M1 to M3, and speakers SP. In addition to being able to conduct video conferences, tablets such as TI or T
3, create a drawing image such as a drawing or memo, or create a drawing information drawn using a light pen W on the screen board SBJ2, and transfer the above drawn image to the other party's printer P or It should be possible to output to the screen board SB.

In the above embodiment, three tablets T I to T3 and three microphones A I to M3 are used, but the number is not limited to this, and the number of each device may be increased or decreased as necessary.

[Effects of the Invention] As detailed above, according to the present invention, in a conventional video conference device, an image data generation means for converting handwritten image information into image data of an electric signal, and an output of the image data generation means are provided. a full-duplex modulation/demodulation means for modulating and outputting the image data to the transmission line, and demodulating the modulated image data input manually via the transmission line; and a demodulated image output from the full-duplex modulation/demodulation means. Since it is equipped with a printer device that outputs and outputs data, it is possible to hold teleconferences between remote locations at any time, and at the same time transmit the audio signals of the conference participants, it is also possible to send drawings or memos or other drawn images to the other party. It can be transmitted to the local device and made a hard copy. Therefore, for a particular meeting participant on the other side,
The present invention is particularly effective when transmitting the above image information.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a television conference device that is an embodiment of the present invention, and FIG. 2 is a block diagram of a full-duplex modem of FIG. 1. 3...Mode switcher, 4...Video signal processing section, 5...Audio signal processing section, 6...Band pass filter (BPF), 7...Hybrid circuit, 8...Band removal Filter (BEF), 9...Telephone line, 10...Full-duplex modem, TI, T2, T3...Tablet, Ml, M2
．． M3...Microphone, W...Light pen, SR...Screen board, P...Printer, SP...Speaker.

Claims (1)

[Claims] (1) In a video conference device equipped with a means for transmitting image signals and audio signals via a transmission line, an image data generation means for converting handwritten image information into image data of an electric signal; a full-duplex modulation/demodulation means for modulating the output and outputting it to the transmission line, and demodulating the modulated image data input via the transmission line; A television conference device comprising: a printer device that outputs image data.