Grandstream Networks GXV3651_FHD user manual Video Settings, Qcif CIF 2CIF

GXV3651_FHD IP Camera

Video Settings

Preferred Video Codec – The GXV3651_FHD supports the H.264 video codec. Resolution – The higher the resolution is, the better the video quality is, and higher bandwidth is required.

Low -----------------------		 High Resolution
QCIF CIF	2CIF	720p

Bit Rate – The number of bits that are conveyed or processed per unit of time. Maximum Frame Rate – The video frame rate is adjustable based on network conditions. Increasing the frame rate will increase the amount of data significantly therefore consuming more bandwidth. Video will be impaired due to packet loss when there is insufficient bandwidth.

Bit Rate Control – Variable Bit rate (VBR) and Constant Bit Rate (CBR).

Variable Bit Rate - If VBR is selected, the codec varies the amount of output data per time segment. VBR produces a better quality-to-space ratio. The bits available are used to enable more flexibly and encode sound or video data more accurately, with fewer bits used in less demanding passages and more bits used in difficult-to-encode passages.

Constant Bit Rate - If CBR is selected, the codec‘s output data is constant regardless of the input data. The output bit rate is defined in ―Bit rate‖. CBR is useful for streaming multimedia content on limited capacity channels. It is easier to calculate required bandwidth as well as the required storage space using CBR.

Image Quality – If ‗Bit Rate Control‘ is set to ―VBR‖, ―Image quality‖ needs to be configured. The better the video quality is, the higher the bit rate will be.

I-frame Interval – While streaming video over a network, compression technologies are used to show the incremental difference between each frame. I-frames are used to help keep the video looking normal. When intervals are shorter, the video quality is higher but uses more bandwidth.

NOTE: The users might need to configure the Primary Stream and Secondary Stream properly. Sometimes, the user might like to watch the live video stream from the web GUI in low resolution mode while recording a copy via GSurf/GS_NVR in high resolution due to the limitation of internet bandwidth. In this case, for example, primary stream can be configured to have better resolution, and then the users can use primary stream to record while watching secondary video streams.

Firmware 1.0.1.32	Page 17 of 36
Grandstream Networks, Inc.	06/2011