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4.1.9. Video Stream Parameter
Select “Stream” label at the right of the video display area to set up the parameters like video definition rate,
and the size of stream, etc. Users can select the video stream type built in the system as well as select the
combination of multi-bit stream types. The default stream 0 is the main stream and the stream 1 is the slave
stream. The stream 2 can be CVBS analog output or HDMI HD digital output.
Fig. 28.
Video Stream types:
The video coding types built-in the system include dual-stream, triple-stream,
dual- CVBS analog output, and dual-stream HDMI HD digital output, etc. If it is required to be tested
via CVBS(That is, BNC interface), please select the video code type with CVBS output. For different video camera
models, the highest definition combination supported by main stream is different. Please refer to Appendix D.
D1 Format Selection:
Image resolution supports 720*576 or 704*576, and user can select according
application, 720*576 defaulted.
Stream Encryption Way:
support “standard data stream” or “encryption data stream”, and user can select
according practical application requirements. When selecting “standard data stream”, back-end video can be
played by general player; while selecting “encryption data stream”, back-end video can only be played by special
player.
Frame rate:
There are many types of frame rate. Full frame rate represents the real-time level with the
highest of 25 frames (PAL mode) or 30 frames (NTSC mode), and the 1/10 level with the lowest of 2 frames (PAL
mode) or 3 frames (NTSC mode).
Coding types:
There are two options: video stream and composite stream. The video stream contains no
audio. However, the composite stream includes video and audio.
Bit rate mode:
It includes two types: fixed bit rate and limited bit rate. Users can select the size of the bit
rate, and also can self-define the upper bound of the bit rate.
Image quality:
It sets up 6 grades from normal to the best. Normally if the image quality is prior without
considering the bandwidth occupation, it can set up to be the best; if the image quality and the bandwidth (bit
rate) are both under consideration, it can set up to be better or even better.
Bit rate upper bound:
32Kbps~2048Kbps. User can self-define the higher bit rate.
Custom bit rate:
When the bit rate type is limited bit rate, users can self-define the upper bound of the bit
rate. For Full HD (1920x1080P), the bit rate is recommended to be 4~6Mbps (4096~6144Kbps); for
HD(1280x720) to be 2~4Mbps (2048~4096Kbps); and for Full D1(720x576) or 960H (960x576) to be 1~
3Mbps (1024~3072Kbps). The highest bit rate can be 8Mbps. The set bit rate cannot exceed the highest upper
bound of the bit rate under each individual definition.
