1, system design features

 

    The main functions of the intelligent multimedia conference system are:

 

    Easy access to the Internet, call data

    You can switch audio and video sources at will

    High quality audio reproduction to ensure voice quality

    Digital conference system control conference speech

    Projection system for large screen display

    Remote conference system for off-site presentations and conferences

    Central control system for centralized control management

 

2, system design

 

    The intelligent multimedia conference system realizes the seamless connection between the digital conference system and the central control system, and integrates the sound reinforcement system, the conference discussion system, the simultaneous interpretation system, the voting system, the automatic tracking camera system, the multimedia video system and the network. The video conferencing system and other subsystems; under the control of the wireless touch screen, through the central integrated control system, the above subsystems and the entire conference environment are organically integrated into one, and the intelligent management of the conference is realized.

 

    2.1 Central Control System

 

    The central control device is the soul of the system design. It integrates lighting, mechanical, projection and video and audio control methods to provide users with a simple and direct control solution, so that users can easily grasp the status of each device in the entire space environment. And function.

 

    The entire system is centered on the central controller. It is connected to each device by the control bus, accepts the control requirements issued by the controller, and then issues control commands to each of the extended control devices and the controlled devices. All control functions are programmed through dedicated system software, and the specific control can be realized by a color LCD touch screen or a normal PC. The operation interface is intuitive and easy to understand (all Chinese, graphic modularization) and operation according to the actual requirements of the user. (As shown in Figure 1)

 

    Control effect:

 

    You can control the operation of various audio and video equipment (such as simple functions such as playing and stopping, and setting advanced settings such as equipment) as needed;

    According to the needs, through the control of various professional matrices and related equipment, complete the switching of various audio/visual/computer signals and adjust the signal path;

    The volume control can be done through the volume control box;

    The incandescent lamp in the conference center can be steplessly dimmed, and the fluorescent lamp group can be switched on and off;

    Through the relay controller, the control of the electric curtain, the electric screen, the switch of the electromagnetic lock and the control of the single glass through the electricity are completed;

    The central control equipment can be designed according to different needs, such as various lighting modes, dimming rate, password protection, etc., and can be adjusted on-site with actual use. It is also possible to write a linked operation program according to the specific needs of the user, and multiple actions can be completed with one instruction.

    Through the RS485 interface, the camera's pan/tilt is used to realize the zoom of the camera of the conference room and the omnidirectional rotation. The video signal of the camera is switched and output to the display device through the audio-video matrix switcher.

    The temperature of the room can be tested by the temperature card and the temperature probe, and the switching display on the touch screen can be realized.

 

    2.2 Acoustic sound reinforcement system

 

    The acoustic effect of the multi-functional conference hall needs to meet the acoustic characteristics index standard of the sound reinforcement system design of the National Hall. On the basis of architectural acoustics, it is generally necessary to compensate for sound effects by using sound reinforcement equipment.

 

    The sound reinforcement system is mainly composed of three parts: sound source, central control processing equipment (mixing console), and speaker system.

 

    Sound source: mainly includes conference microphones, recording and playback decks, DVD players and other sound source devices, which can play ordinary or metal tapes, CDs, DVDs, video recorders, and video cassettes for high-quality recording of conference broadcasts.

 

    Multi-channel conference dedicated mixer: It is the central control device of this system, which can mix and amplify and switch multiple audio signals, adjust the high and low sounds, effect compensation control, volume adjustment, recording and playback;

 

    Speaker: The sound quality and sound field uniformity of the entire sound reinforcement system depends mainly on the quality and arrangement of the speakers.

 

    The sound reinforcement system design usually starts from the sound field design. Because the sound field design is the basis for satisfying the system function and sound effect, the selection of the speaker system, the sound supply scheme and the signal path are very complicated and cumbersome work. Due to the rapid development of computer technology, special acoustic software tools can now be used for calculation to obtain a sound field design that meets the expected requirements. After the speaker system is determined, the calculation of the power amplifier driving power and the determination of the driving signal path can be performed; then, the signal processing scheme and the selection of the mixer are further determined according to the driving power allocation scheme.

 

    2.3 Conference speech system

 

    The conference presentation system includes a hand-in-hand conference discussion system, a voting system and a simultaneous interpretation system.

 

    2.3.1 Hand in hand meeting discussion system

 

    All the microphones in the system are connected in series by dedicated lines, and finally to the conference host, as if they were hand-in-hand. During the large-scale group meeting, there are many speakers at the meeting. The hand-in-hand meeting system can ensure that everyone can speak easily and at the same time facilitate meeting management.

 

    The system generally consists of one chairman speaking machine (control machine) controlling multiple representative speakers. The system components and functions are as follows:

 

    Chairman's speaking machine: has the right to speak first, control the right to speak and set the system; each system sets a chairman machine;

 

    Vice-Chairman's speech: has the right to speak first, control the right to speak; each system sets a vice-chair;

 

    On behalf of the speaking machine: with the function of applying for a speech, queuing a speech, listening to a speech; each system can be set up with 5~120 speaking representatives;

 

    Conference host: accept the instructions of the chairman machine to control the delegate machine.

 

    2.3.2 Voting System

 

    Add voting function to each device of the conference discussion system for elections and voting meetings. Its main equipment includes:

 

    Voting: Let the delegates use to vote;

    Data display: used to display information such as meeting agenda, representative and conference background information, voting results, etc.

    Representing the identity manager: used to confirm the identity;

    Voting Management Software: This software is used to manage complex voting conferences, including microphone management, voting management, check-in management, and simultaneous system management.

 

    2.3.3 Simultaneous Interpretation System

 

    Used for international conference exchanges. In the process of meeting with representatives of multilingual participants, when speaking in a representative of any language, the simultaneous translators can instantly translate into other languages ​​and send them to each participant through the language distribution system. Listen to the language you know and achieve the purpose of multilingual communication.

 

    The system adds the language channel selection function in the simultaneous interpretation system to each device of the conference discussion system, and correspondingly adds the following device components:

 

    Interpreter: Let the translator transfer the translated language to the system and let the delegates listen;

    Language distribution system: The language distribution system of the simultaneous interpretation system can be divided into wireless or wired;

    Wireless--flowable, high equipment and space utilization, the disadvantage is that the equipment is expensive, the confidentiality is not as good as the wired type; now the infrared wireless system is used, the performance is stable, the infrared rays can not pass through the wall, and the confidentiality;

    Wired--the equipment is cheap, stable in performance, low in maintenance cost, and confidential; the disadvantage is that the construction is complicated and inconvenient to use.

 

    2.4 Automatic tracking camera system

 

    The automatic tracking camera system provides high quality live video image signal resources for meetings. It can be activated by a digital speaking system to accurately and quickly close the speaker in the absence of maneuvering. The acquired signals can be output to a large-screen rear projection system and a remote video conferencing system.

 

    In general, the automatic tracking camera system requires several high-speed dome cameras to be mounted longitudinally at the top of the conference table. The main function is to collect close-ups of the speaker. Install a panoramic fixed camera above the large screen of the conference room to capture the full screen when no one is speaking.

 

    A control port of the central controller of the speaking system is connected to the control port of the video matrix. When a microphone of the speaking system is turned on, the central controller sends a serial command to the video matrix, and the video matrix is ​​corresponding according to a preset operating procedure. The camera issues an operation command and simultaneously outputs the captured signal of the camera from the output port to the conference video system or the remote video conference system.

 

     2.5 Multimedia Video System

 

    With the development of computer technology, multimedia video system has become an indispensable part of modern conference system. Its content mainly includes projection system, physical projection system and smart whiteboard that can be connected to meet the needs of modern information exchange. Through it, other existing signals, such as closed-circuit television, broadcast television, and network television conference signals, can be sent to the multimedia conference system; the multimedia conference signals of each venue can also be sent out to the network exit for network video conference exchange.

 

    Multimedia Projector: Professional multimedia projector with high brightness (2900ANS lumens), high resolution (1024*768 and 1280*1024), true color display function, not only video images of video recorders, LDs, DVD players, but also video images. Computer graphics text (or computer network information) can be projected on a large screen (150 inches). This function is especially suitable for project introduction, lecture teaching, etc.

 

    Physical display stand: high-brightness physical display stand, which can send any physical objects, lectures and slides to the projector after shooting, and project on the big screen to show the audience;

 

    Electronic whiteboard: This device can project the display content of the notebook computer used in the lecture on the electronic whiteboard through the projector, and let the lecturer conveniently control the computer demonstration program directly on the electronic whiteboard, and write, mark, and save the disk. It can be discussed at the same time through network conference equipment, which is a necessary and effective communication tool for modern multimedia conference systems.

 

    2.6 Remote Video Conference System

 

    The remote video conferencing system uses the communication line to transmit the image, sound, and conference materials and related physical images of the participants in two or more conference venues in real time, so that participants in different locations can see each other as if they were in the same place. Sitting in the same meeting room as a meeting.

 

    At present, most remote video conferencing systems are based on IP networks, and generally consist of several multimedia conferencing terminals, an IP network, and a multipoint control server. The conference terminal refers to a multimedia PC equipped with a video capture device camera and codec card, an audio input and output device microphone and speaker, and a terminal application; the multipoint control server is a high performance server. A typical centralized multipoint conference is that all terminals send video streams, audio streams and control streams to the multipoint control server in a point-to-point manner. The multipoint servers follow a certain control protocol to centrally manage the conferences for mixing and data. Allocation and video signal mixing and switching, and the processing results are sent back to the terminal participating in the conference.