Longvast GVP-201, Руководство пользователя

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Note: the users may right-click and choose VLC program’s “Full Screen” mode too.
Resolution -
The resolution here describes an image size counted by width and height, e.g. 640x480, referring to pixel
resolution . The 1
st
stream can be set from more options of resolution; 1600x1200 (2 megapixels),
1280x720(HD), 800x600(SVGA), 640x480(VGA), 320x240(QVGA). While Stream2 has the options of VGA
and QVGA, stream3 is in a fixed resolution, the QVGA. The users need to decide which resolution and frame
rate options to be selected according to the requirements and practical constraints from the bandwidth and
storage available.
Video Mode -
This option allows the selection of two bit-rate modes, the Constant Bit Rate (CBR) or Variable Bit Rate (VBR).
CBR refers to the setting of a fixed Target Bit Rate (configuration in the range of 64Kbps to 6Mbps) that
would apply in the case of limited bandwidth or/and storage requirement. While CBR concerns a fixed data
rate transmitting, the video quality setting is of high priority for VBR mode selected. VBR therefore is
configured with the Quality Level (Standard, Good, Best). In general, CBR predicts the provided condition; if
image activity requires higher bit rates than configured, the frame rate and quality would be affected as not
likely to increase bandwidth (bit rate). In spite of the required recording storage estimation, VBR is by way of
compensation that adjustable bit rate fits the actual image activity.
Image Format -
H.264 and MJPEG are available for image format selection. The term, “image format”, is referring to
compression / encoding technique. The selection of image format decides the performance of bandwidth and