Messoa SPD970, Руководство пользователя

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Table 3 - 2: Edit Profile Options
Item Option Description
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 file 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 file size is prone to be
smaller compared with MJPEG.
Resolution
3M(2048×1536) , 1080P(1920×1080) ,
SXGA(1280×960) ,720P(1280×720),
SVGA(800×600), VGA(640×480), VGA
(640x360), QVGA(320x240), QVGA (320x180)
3M(2048×1536) is the highest resolution
QVGA (320x180) is the lowest resolution.
Frame Rate (fps)
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@15fps;
H.264/MJPEG single stream: 1920×1080 to 320x180@30fps
PAL: H.264/MJPEG single stream: 2048×1536@15fps;
H.264/MJPEG single stream: 1920×1080 to 320x180@25fps
GOP (Group Of
Pictures) Length
NTSC / PAL: 1~254
Select the GOP length number rangingfrom1 to 254.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 default GOP Length is 30
QoS (DSCP)
Codepoint
0 ~ 63
To classify and manage network traffic 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.
Bit Rate Mode
CBR: Constant Bit Rate
VBR: Variable Bit Rate
Choose the bit rate control selection based on user
requirements. Higher bit rate values will result in better
quality with bigger file size and thus consume more network
bandwidth. CBR stands for constant mode with certain fixed
rate by user definition, while VBR means variable mode in
which users can set a range of upper and lower limits
respectively for bit rate control.