HUAWEI VP9050 Executive Video Terminal |
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User Guide | DGlossary | ||
dual stream | During a conference, two channels of video streams can be sent or received |
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| simultaneously. For example, one channel is used for transmitting video (such as |
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| video captured by a camera) and the other channel is used for transmitting |
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| presentation (such as a computer desktop). The two channels of videos can be |
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| displayed on two displays. |
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G.711 | G.711, also known as Pulse Code Modulation (PCM), is a very commonly used |
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| waveform codec. G.711 uses a sampling rate of 8,000 samples per second, with the | ||
| tolerance on that rate 50 parts per million (ppm). |
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| (logarithmic) with 8 bits is used to represent each sample, resulting in a 64 kbit/s bit | ||
| rate. There are two slightly different versions; |
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| North America, and |
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| America. |
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G.722 | G.722 is a | ||
| kbit/s. It was approved by |
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| based on |
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G.728 | G.728 is an | ||
| described as Coding of speech at 16 kbit/s using |
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| prediction. |
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give floor | After the chair site gives floor to a site, the other sites view and hear the site. All the | ||
| sites, except the chair site and the site that is given the floor, are muted. |
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H |
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H.239 | H.239 is an | ||
| macrofamily of standards for multimedia communications over various networks. |
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| The H.239 recommendation is titled "Role management and additional media |
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| channels for | ||
| its setting forth a way to have multiple video channels (for example, one for |
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| conferencing, another for presentation) within a single session (call). |
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H.261 | H.261 is a 1990 | ||
| over ISDN lines on which data rates are multiples of 64 kbit/s. It is one member of | ||
| the H.26x family of video coding standards in the domain of the |
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| Coding Experts Group (VCEG). The coding algorithm was designed to be able to |
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| operate at video bit rates between 40 kbit/s and 2 Mbit/s. The standard supports two | ||
| video frame sizes: CIF (352x288 luma with 176x144 chroma) and QCIF (176x144 | ||
| with 88x72 chroma) using a 4:2:0 sampling scheme. It also has a |
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| resolution and 352x288 chroma resolution (which was added in a later revision in |
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| 1993). |
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H.263 | H.263 is a video codec standard originally designed as a |
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| format for videoconferencing. It was developed by the | ||
| Group (VCEG) in a project ending in 1995/1996 as one member of the H.26x family | ||
| of video coding standards in the domain of the |
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| support for flexible customized picture formats and custom picture clock frequencies. | ||
| Previously the only picture formats supported in H.263 had been | ||
| CIF, 4CIF, and 16CIF, and the only picture clock frequency had been 30000/1001 |
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| (approximately 29.97) clock ticks per second. |
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Issue 03 | Huawei Proprietary and Confidential | 110 |
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| Copyright © Huawei Technologies Co., Ltd |
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