Digital Watchdog MEGApix Flex DWC-PVX20WATW User Manual page 19

Setup - Video & Audio Setup
Video Configuration
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GOP (Group of Pictures) Size - Set the number of frames (P-frame) which contain only changed
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information based on the basic frame (I-frame). For videos with lots of movement, set the GOP value higher to
capture more P-frames. In this case, the video resolution will be lower but 'File size' and 'Bit-rate' can decrease.
GOP (Group of Pictures) Size -
'I-frame', also known as 'key-frame', refers to the complete image data for a specific video frame. 'P-frame'
refers to the changes in the image in comparison to the previous video frame. The GOP consists of one
I-frame and several P-frames. For improved video quality, use a lower number of P-frames.
Profile - The profile defines the subset of bitstream features in H.264, H.265 (HEVC) stream, including color
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reproduction and additional video compression.
H.264: Main, High / H.265 (HEVC): Main
Main - An intermediate profile with a medium compression ratio. Supports I-frames, P-frames and B-frames.
High - A complex profile with a high compression ratio. Supports I-frames, P-frames and B-frames.
Bitrate Mode - Select the bit rate control scheme of video compression from CBR (Constant Bit Rate) or VBR
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(Variable Bit Rate).
CBR - To guarantee the designated constant bit rate, the quality of the video is controlled in this
mode. Therefore, the quality of the video is likely to be varying when network traffic is changing.
VBR - To guarantee the designated quality, the bit rate of the video stream is changed in this mode.
Therefore, the frame rate of the video is likely to be varying when network traffic is changing.
This category will not appear if you select the codec.
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