Video Grabber DGR-1000 User Manual - v. 1.4 (FW 1.9)
35
ID
Section
Description
1
IDR
I-Frame period – determines the frequency at which I-Frame (frame
that contains a full picture) will be generated. e.g. 200 means that I-
Frame will be generated after every 200 P-Frames which means that
every 200
th
frame will contain a full picture while all the frames ‘in
between’ will only contain changes in relation to the previous frame.
High IDR period usually results in lower network utilization as P-Frame
is usually much smaller than I-Frame
5
.
Allowed values:
Integer <1; 65535>
Table 20: RTSP protocol setting common for H.264 and Lossless (LLE)
ID
Section
Description
2
LAN 1
RTSP connection string for H.264 format available on LAN 1
Read only
3
CBR mode
When selected H.264 codec works in CBR mode, when not selected
then the H.264 codec works in VBR mode.
CBR – Constant Bit Rate – amount of data sent will be constant. When
there is a lot of activity on the captured screen then the quality of the
Video Grabber’s output stream will be lowered to comply with CBR
kbps limitation.
VBR – Variable Bit Rate – amount of data sent will vary depending on
the amount of activity on the captured screen. Quality of the Video
Grabber’s output stream is determined by the value of the QP
parameter.
4
Quantization
Parameter (QP)
Used to adjust the quality of image in VBR mode (available only
when
3
is not selected). Lower values produce better quality and
higher bit rates. Higher values produce lower quality and lower bit
rates.
Allowed values:
Integer <0; 51>
5
LAN 2
RTSP connection string for H.264 format available on LAN 2
Read only
6
Bitrate (kbps)
Constant Bitrate setting in kbps. Available only when
3
is selected.
Sets the bit rate limit for the RTSP stream.
Allowed values:
Integer <10;40000>
Table 21: RTSP protocol settings for H.264 format
5
In extreme situations – when screen contents change very fast – it may happen that P-Frames are actually
bigger than I-Frames.