Stream Profiles Page Features (Cont.)
Feature | Description |
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• Video In Rate | A |
| video data throughput available for use by the |
| • The larger the amount of available video data coming through the unit for encoding, |
| the better the outgoing video quality to the target IP device. |
| • Available video data rates: 6Mbps - 500Kbps |
• Resolution |
|
A | |
| resolution types. These options relate to the display size/resolution used by the outgo- |
| ing video stream. |
| • Available resolutions: D1 (default) or SIF: |
| • D1 is a resolution standard. In the NTSC system, "Full D1" means 720x480 pixels @ |
| 30 fps, and in PAL systems, full D1 is 720x576 @ 24 fps. |
| • SIF (Source Interchange Format) is a resolution standard defined as 352x240 @ |
| 30fps for NTSC and 352x288 @ 24 fps for PAL. |
• Mode |
|
These two radio boxes refer to the mode assigned to the bit rate encoding quality of the | |
| outgoing A/V stream. |
| Available bit rate encoding modes: CBR (default) or VBR |
| • CBR (Constant bit rate) relates to the bit rate quality used by the outgoing streamed |
| video data. Constant bit rate encoding means that the rate at which a codec's output |
| data should be consumed is constant. CBR is useful for streaming multimedia |
| content on limited capacity channels since it is the maximum bit rate that matters, not |
| the average, CBR would be used to take advantage of all of the capacity. |
| • VBR (Variable bit rate) relates to the bit rate quality used by the outgoing streamed |
| video data. Variable bit rate encoding varies the amount of output data in each time |
| segment based on the complexity of the input data in that segment. The goal is to |
| maintain constant quality instead of maintaining a constant data rate. |
|
|
Audio: | This section allows the user/administrator to define the encoding parameters for the |
| audio portion of the outgoing stream. |
|
|
• Codec | A |
| audio compression used for the audio portion of the outgoing stream. |
| Available audio codecs: MP2 or MP3 |
| • MP2 (MPEG Audio |
| of this type. It remains a dominant standard for audio broadcasting. This file type |
| allows the coding of audio programs with more than two channels. The main |
| difference between these two types is that MP2 audio files are generally larger than |
| their MP3 counterparts and are mostly used with |
| Note: MP2 is recommended for use with a high bandwidth video stream (ex: |
| or 6 Mbps - 3 Mbps). |
| • MP3 (MPEG Audio |
| compression format. It was designed to greatly reduce the amount of data required to |
| represent the original audio data, yet still sound like a faithful reproduction of the |
| original uncompressed audio to most listeners. |
| Note: MP3 is recommended for use with a low bandwidth video stream (ex: |
| or < 3 Mbps). |
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