Task 1: Read and translate the text in written form

The Video System 
The modern video conference system also makes extensive use of other video 
sources such as interactive computer presentations to augment the communication. 
This can be especially valuable for technical applications where models, drawings, 
sketches, and broken or defective parts can be shown to the receiving station. In 
addition to standard video sources, the use of interactive displays or collaborative 
computing software on tablets allow material displayed in the source room to be 
shared at the receiving end. Where a similar interactive computer is located in the 
receiving station, true interactive design, troubleshooting and problem solving can 
take place in near real time. 

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8 
Where the video conference room also functions as a meeting room, the video 
display for the video conference system can be made to double as the display for 
meeting support materials. The same document camera, as well as other video 
devices, can be used with these display systems. 
The Audio System 
The audio system has four major components: one or more microphones (and 
mixer if required); the loudspeaker system; the video codec and digital phone 
hybrid that handles the signal processing allowing full duplex (two way) 
conversation and transmission/reception of the signals; and the acoustic echo 
cancellation (to prevent the source station hearing itself amplified and re-
transmitted from the receive location). The performance of the entire audio chain is 
directly tied to the room acoustics. The performance of the echo cancelling is 
directly tied to the decay of sound in the room, and the quality of microphone 
pickup is likewise affected by early reflections and reverberation. This is the 
reason we emphasize the importance of room acoustics as part of the system 
design. 
Microphone placement plays an important part of the sense of distance between the 
talker and the receiving station. We are all familiar with the "group of people in a 
barrel" sound of a speaker phone. The speaker-phone sound results from a 
combination of an omni-directional microphone and hard surfaces in the room. The 
way to beat that tell-tale sound quality is by using appropriate microphones, getting 
the microphone closer to the talkers in the source room, and controlling the 
reflections from hard walls. This can help make a video conference sound like a 
cross-the-table meeting.