Eneo IPD-72M2713MAA, Руководство пользователя

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Full Menu Setup
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MEGA-PIXEL NETWORK CAMERA
> BITRATE Quality : Enables to set the quality.
> BITRATE : Indicates the transmission speed through the network and defines the overall
picture quality along with the image resolution, frame rate, GOP size and the compression
codec for H.265, H.264. A high value provides the higher image quality but the total
sum of bitrates for the streams has to be considered in calculating the network duty.
> BITRATE CONTROL : Selects how to manage the bitrate.
• VBR (Variable Bit Rate):
Provides the higher image quality with the optimal variable bitrate for the scene
which has more moving elements in the image. It is not recommended when network
is in heavy duty.
• CBR (Constant Bitrate) :
Tends to keep the bitrate steady at the assigned bitrate within a very small variation.
It is useful when the network is in very heavy use.
> GOP SIZE: GOP (Group of Picture) defines the number of Intra-coded pictures (I frame)
& Predictive-coded pictures(P frame) in H.264. I frame is a complete image while P frame
is the predictive image data which can lower the image data dramatically between frames.
GOP SIZE stands for the number of P frames between I frames. Too small GOP SIZE
(too frequent I frames) can degrade the picture quality because the codec compresses
the data strongly to maintain the bitrate. On the contrary, a little bigger GOP SIZE can
improve the picture quality with the better quality for P frames if the network is in good
condition. Too big GOP SIZE can make the longer black out or the broken image if the
network quality is not good enough.