Which of the following protocols belongs to the encapsulated transport protocol ( ).
Horizontal viewing is the angle between the audience's eyebrows and the ends of the screen in a horizontal direction.
What properties does the color rendering index affect on the color of a video image?
Multi-channel cascading, mainly through the establishment of multiple cascaded channels between the cascading conferences of the MCU, the multi-channel code stream on the MCU is sent to the peer
MCU.
Peer-to-peer calls between endpoints must use an MCU, but multipoint meetings can be scheduled without an MCU.
Diagnosis of peer-to-peer networks without networking traversed by public and private networks. ( )
Speech enhancement technology Jitter Buffer is the use of a human intervention signal wave, to eliminate the echo signal generated during the communication process, while retaining other normal voice
signals, in order to achieve the normal communication Use. ( )
When using MCU wall riding mode, the terminal on the GE0 side can call the terminal on the GE1 side over IP.
In the camera control of the WEB interface, only the local camera can be controlled, not the remote camera. ( )
In the SMC2.0 system, ( ) has the highest level of user rights. (Fill in the blanks)
The opening process of the logical channel in the H323 protocol follows the principle of "who transmits, who opens". ( )
Fe and GE0, GE1 IP addresses can not be in the same network segment, otherwise it will cause network failure, at this time the front panel ALM light is always on.
If you accidentally drop the meeting in the terminal meeting, you can join the meeting by calling the special service number.
SIP is an application layer protocol that is independent of the transport layer protocols below and can be hosted on different transport protocols, such as UDP/TCP/TLS/SCTP, currently Most commonly used
TCP. ( )
Only if the terminal supports T.140, you can use the T.140 method to send banners, subtitles, or short messages to a specified venue.
Due to the size of the display and the limitation of MCU resources, the number of multi-screen sprites generally does not exceed 16 sprites, otherwise the image is too small and the picture will not be clear.
In an RTP packet, the initial value of the Sequence number is random, no RTP packet is sent, and the sequence number is incremented. The receiver detects packet loss and rebuilds packets based on it.
In the SMC2.0 system, which of the following user rights has the highest level.
Which of the following signaling signalings can the gatekeeper issue address resolution requests to other gatekeepers?
Under static NAT networking, the SRC address of the terminal under the private network changes to ( ).
The following description of the cascading characteristics of the miniMCU is correct. () (3 answers).
A single value in a header field can only appear once in a message, such as Via, Route, etc.
Video conferencing has certain requirements for lamps, and the lamps used require strong light efficiency, uniform and soft light, and make full use of diffuse reflection.
Multicast is a networking technique that allows one or more senders (multicast sources) to send a single packet to multiple receivers (once, simultaneously).
When querying the "System Status" on the web interface of the RSE6500, which of the following information cannot be obtained?
PCM coding mainly includes three processes: sampling, quantization, and coding. ()
Which of the following protocols is a dual-stream protocol in the H.323 protocol stack?
The types of terminal faults can be summarized as: local AV faults, remote AV faults, and call and conference control problems.
RTP is a real-time transmission control protocol: on multicast (multicast) or unicast (unicast) network services, provides end-to-end network transmission capabilities, suitable for applications to transmit real-time data, such as audio, video or simulation data.
In a networking network, the H.245 TCP connection of the private network terminal is established with TS.
Which of the following measures can users use to expand the video port of the VP9650 ?
If both the sender and receiver () are the same, the MCU forwards directly. (3 answers).
At the end of the meeting, the recording server returns the recording address to the SMC, and the SMC emails the user to watch on demand.
The chamber sound reaches a stable state during reverberation time, and the residual sound is repeatedly absorbed by the sound absorbing material in the room after the sound stops, and the original value
of the average sound energy density word decays to one part in a million (Acoustic code attenuation 60dB). The time required, expressed in T60.
Image format refers to the size or resolution size of the image, common image formats include, SOCIF, QCIF, CIF, ACIF, 16CIF, HD, Full HD. ( )
Color temperature affects the white balance of the camera, and where the color temperature is complex, the image can be cast.
The difference between Ad Hoc conferencing and traditional video conferencing systems is that you can create and join meetings on the terminal side without an administrator.
VR can be understood as an interactive way to guide users to a destination meeting or create a meeting. ( )
The feed can be either the active image or the contents of the computer desktop. ( )
The video signal starts from the input terminal device, is encoded and compressed and sent to the network, and finally displays, and has undergone many image processing links in the middle, mainly
including: IP Camera, pre-processing, compression encoding, data encapsulation and transmission, decoding, image format variation , broadcast. ( )
Packet loss retransmission ARQ, similar to TCP's retransmission mechanism, requires the peer to resend the UDP when the UDP packet loss of the video stream is detected in the network Stream, the
receiving side stores the received stream in a certain cache, and only opens the decoding after receiving the retransmitted stream.
Several video compression standards that are currently widely used include: H.261H.263 and H.264 and MPEG-1. MPEG-2 and MPEG-4. Its H.26X series of standards is primarily used for real-time video
communications, and the MPEG series of standards is primarily used for video storage (DVD), video broadcasting, and video streaming.
In video conferencing, the empty field noise is required not to be greater than ( )dB. (Fill in the blanks)
In multi-channel cascading, two MCUs in a conference support up to ( ) cascaded channels
In audio encoding, which of the following is a speech quality metric. () (3 answers).
The standby GK completes the following procedures ( ) in response to a synchronization request.
Under static NAT networking, the signaling description of the public network terminal calling the private network terminal is correctly ( ).
Private network HD terminals use static NAT for public and private network crossing, regarding the calls between terminals, the following statement is incorrect ().
In the RTP specification (RFC3550), a total of ( ) types of RTCP reports are defined to report current control information.
Regarding the Client proxy in the H.460 protocol, the following description is correct ( ).
The SIP protocol's flexible scaling mechanism refers to the addition of header domains and message types.
Under static NAT networking, the SRC address of the terminal under the private network changes to ().
The ( ) function in Wireshark visualizes the conversational communication process graphically.
Video compression includes intra-frame compression (I frame) and inter-frame compression (P frame), common H.26X, MPEG-2, MPEG-4 Both support in-frame/inter-frame compression.
Three-color lamp refers to the use of red, yellow, blue three color spectrum of the lamp and light emitting lamps, the general luminous color and the color temperature of the lamp has a relationship, with a soft luminous light, uniform brightness, no stroboscopic, high visibility, small power consumption, high voltage resistance, no electric heat disaster characteristics.
RFC2190 defines a total of 3 load heads for the H.263 video codec format: mode A and mode B and mode C/A mode is the recommended and commonly used transmission mode. ()
When the speech codec capability is negotiated in the SIP protocol, the voice codec supported by the local device is provided, including PCMU and PCMA Based on the RTP message shown in the figure, it can be seen that the ( ) voice codec is selected.
After the video terminals A and B join the same video conference, the user of terminal B reflects that the video image of terminal A is more continuous, but not clear enough, and the administrator of terminal A performs the video self-ring and finds that the image of the self-ring is clear. From this, we can infer that the cause of this phenomenon is caused by the high image rate set by terminal A.
Which of the following in the header domain is used to represent the SIP entity through which the request passes and the route response?