JPS649796B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a video conference device used when a plurality of people hold a conference between distant locations.

Conventionally, in this type of video conferencing device, when a single camera is used on the transmitting side to capture images of multiple meeting participants, and when the images are received and displayed on a receiver on the receiving side, the images of the people become too small and it is difficult to speak. The drawback was that it was not possible to clearly recognize people.

The purpose of the present invention is to provide an identification means for identifying a speaker, an allocation means for allocating this on an image, a suppression means for suppressing other image areas, and a method for making a receiver aware of the above. The above-mentioned drawbacks are eliminated by providing recognition means for the speaker who gives the maximum audio input level to the microphone among the plurality of conference attendees whose images are captured by one camera on the transmitting side. is detected and generates a speaker identification signal, suppresses the average level of the video signal of the range of conference attendees other than the speaker, and displays the video signal at low brightness on the receiving side to identify the speaker on the receiving screen. An object of the present invention is to provide a video conference device that makes it possible to clearly recognize people.

The video conference device according to the present invention transmits video signals captured by a plurality of cameras on a transmitting side via a transmission path, receives the video signals using a plurality of receivers on a receiving side, and also so that the audio signals collected by multiple microphones are played back to the receiving side's public address system.
It is configured to mutually transmit and receive video and audio signals between distant locations. In the present invention, the above-mentioned apparatus includes an identification means, an allocation means, a suppression means, and a recognition means. The identification means generates a speaker identification signal by comparing the levels of speech audio signals collected by microphones prepared by each conference attendee,
This is to detect and identify the speaker at the maximum voice input level. The allocation means is for allocating a horizontal video signal period in the video signal captured by the camera according to the number of conference attendees. The suppression means is a means for suppressing the average level of the video signal outside the range to which the speaker belongs in the video signal using the speaker identification signal. The recognition means generates and transmits a suppressed video signal so that when the receiving side receives the video signal,
This is to clearly detect and identify the speaker based on differences in local average levels of received images.

Next, embodiments of the video conference device according to the present invention will be described in detail with reference to the drawings.

In the present invention, FIG. 1 is a block diagram of a transmitting side which is equipped with means for making the speaker on the transmitting side clearly recognized by an image to all conference participants on the receiving side. In Figure 1, 1 is a microphone group, 2 is a microphone amplification circuit group, 3 is an analog/digital conversion circuit group, 4 is a comparison detection circuit, 5 is a video signal control circuit, 6 is a camera, and 7 is an analog/digital conversion circuit. , 8 is a switching circuit, 9 is a video signal level attenuation circuit, 10 is a delay circuit, 11 is a video synthesis circuit, and 12 is a digital/analog conversion circuit.

In FIG. 1, an audio signal collected by a microphone group 1 consisting of a plurality of microphones is amplified by a microphone amplification circuit group 2, and then converted by an analog/digital conversion circuit group 3.
It is converted into a PCM code and input to the comparison detection circuit 4. The comparison detection circuit 4 compares the microphone input signals converted into digital signals, performs arithmetic processing, and detects the microphone having the maximum input level based on the speaker identification signal.

FIG. 2 is a diagram showing a gate signal for selecting the speaker's position in the video signal control circuit 5 of FIG. 1. That is, as shown in FIG. 2, the video signal control circuit 5 divides the horizontal video signal period according to the number of conference participants, gates the speaker identification signal from the comparison detection circuit 4, and determines the speaker's position. A speaker gate signal for identification is generated. This signal is latched until the input level of another microphone is at maximum. On the other hand, the video signal input from the camera 6 is converted into a PCM signal by the analog/digital conversion circuit 7, and then the switching circuit 8
is input. The speaker gate signal from the video signal control circuit 5 is input to the switching circuit 8 as a select signal indicating the speaker's position, and the video signal is output to the speaker's position and to positions other than the speaker.
Here, the video signals of those other than the speaker are input to the video signal level attenuation circuit 9, and the signal level is digitally divided and suppressed to a preset level. At this time, the pedestal level of the video signal and the amplitude of horizontal/vertical synchronization are not changed. The video signal of the speaker's part and the selector signal are both input to the delay circuit 10, delayed by the amount of delay by the signal level attenuation circuit 9, and then input to the video synthesis circuit 11. The two phase-matched video signals are sent to the video synthesis circuit 11.
After being synthesized again by the digital/analog conversion circuit 12, it is converted into an analog signal.
When this output video signal is displayed on a receiver, as shown in FIG. 3, the brightness of images other than the speaker becomes low, so that the speaker's position can be clearly recognized visually.
That is, FIG. 3 shows an example in which the video signal of the speaker's part is left as is, and the receiver receives a signal in which the average level of the video signal of the range other than the speaker's part is suppressed. FIG. 4 is a diagram showing the transmitted video signal at that time.

As explained above, the present invention detects the position of the speaker on the transmitting side and suppresses the level of video signals for signals other than the speaker, thereby detecting the speaker when the image is displayed on the receiver. This has the effect of allowing for clear recognition and allowing the meeting to proceed extremely smoothly.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the transmitting side of an embodiment of a video conference apparatus according to the present invention. FIG. 2 is a diagram showing an example of a gate signal for selecting the speaker's position in the video signal control circuit shown in FIG. 1. FIG. 3 is a diagram showing an example of a received image in which the average level of the video signal is suppressed in a range other than the speaker. FIG. 4 is a diagram showing the video signal in FIG. 3. 1... Microphone group, 2... Microphone amplification circuit group, 3... Analog/digital conversion circuit group, 4... Comparison detection circuit, 5... Video signal control circuit, 6... Camera, 7... Analog/digital Conversion circuit, 8...Switching circuit, 9...Video signal level attenuation circuit, 10...Delay circuit, 11...Video synthesis circuit, 12...Digital/analog conversion circuit.

Claims (1)

[Claims] 1. On the transmitting side, video signals captured by multiple cameras are sent out via a transmission path, on the receiving side, the video signals are received by multiple receivers, and on the transmitting side, the video signals are transmitted to multiple microphones. In a video conferencing device configured to mutually transmit and receive video and audio signals between distant points, so that the collected audio signals are played back by a public address system on the receiving side, conference attendees can each identification means for generating a speaker identification signal by comparing the levels of speech audio signals collected by a prepared microphone to detect and identify the speaker with the maximum audio input level; and an image captured by the camera. Allocating means for allocating a horizontal video signal period according to the number of conference participants in the signal, and suppression for suppressing the average level of the video signal outside the range to which the speaker belongs in the video signal by the speaker identification signal. and a recognition means for generating and transmitting the suppressed video signal so that when the receiving side receives the video signal, the speaker is clearly recognized based on the difference in the average level of the parts of the received image. A video conferencing device comprising: