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Table 4 - 2: Edit Prole Options
Item Option Description
Corridor
ON
OFF
In certain of the vertical oriented shape applications, e.g., sideway, aisle,
corridor, because of the attribute that requires more details in vertical areas,
the prevailed 16:9 aspect ratio is not that appropriate and large portion of
bandwidth are wasted in landscape field of view. Consequently, in order
to optimize the image result for corridor-like applications, click “On” to
enable this function so that the image will be rotated back 90 degrees to
a 9:16 aspect ratio that perfectly fits portrait-like environments, reducing
bandwidth and storage wastes.
Compression
QXGA(2048×1536) , Full HD(1920×1080),
QuadVGA(1280×960) , HD(1280×720),
SVGA(800×600), VGA(640×480), VGA
Wide(640x360), QVGA(320x240), (320x176)
QXGA(2048×1536) is the highest resolution
(320x176) is the lowest resolution.
Codec
MJPEG
H.264
MJPEG: Each video frame is individually compressed as single jpeg image
with full-scale contents itself and can be retouched freely with ease.
However, due to completeness of each frame, it brings about larger le size
and thus easily tends to lose frames under limited network bandwidth.
H.264: The latest best-renowned video compression format, it adopts
intelligent technology to record variation in each frame rather than record
each full frame. As a result, less network bandwidth it requires and le size is
prone to be smaller compared with MJPEG.
DSCP 0 ~ 63
To classify and manage network trac and provide quality of service (QoS)
on modern IP networks, Differentiated Services Code Point (DSCP) is a
computer networking architecture that specifies a resource allocation to
each device on a priority-based pattern for ideal bandwidth management.
The bigger value, the higher priority it will be.
Prole
Main
High
Baseline
There’re 3 kinds of proles for H.264 codec and the compression ratio with
protocol for each type are different. Users may choose a proper one for
desired applications or contact IT personnel for more information.
Frame Rate
NTSC: 1~30
PAL: 1~25
The utmost fps settings for 2 systems varies as the following:
NTSC:
H.264/MJPEG single stream: 2048×1536 to 320x176@30fps
PAL:
H.264/MJPEG single stream: 2048×1536 to 320x176@25fps
Rate Control
CBR
CVBR
Choose one of the Rate Control modes depending on dierent situations.
Higher bit rate value will result in better quality with bigger file size and
thus consume more network bandwidth, while lower bit rate value, instead,
has slighter loading on network bandwidth due to smaller le size but with
inferior image quality.
GOP (Group Of
Pictures) Length
NTSC: 1~60
PAL: 1~50
Select the GOP length number from NTSC: 1 to 60 / PAL: 1 to 50. Less number
means the distance between 2 I-frames is smaller, which needs more
network bandwidth with better image. By contrast, larger number consumes
less bandwidth but is hard to be recovered. The available length number
options of GOP will vary based on frame rate settings.
M-JPEG Quality
Level
Low/Mid/High
While “Low” produces the highest image quality, it increases the le size; on
the other hand, “High”, the lowest image quality, decreases the le size.