DF4900HD / DF4500HD
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Variable bit rates make better use of the available hard disk space.
GoP-size
The GOP-size (Group Of Pictures) specifies how images are used to generate the H.264
data stream.
The higher the GOP-size is, the better the image quality. However, a higher GOP-size will
also result in an increase in the delay.
A GOP-size between 6 and 15 generally provides a good image quality with high compres-
sion.
A GOP-size of 1 denotes a low compression factor and should only be used for special ap-
plications (e.g. in multiplex mode).
GOP-sizes greater than 15 belong to the extended GOPs.
Reverse playback has limited quality (frame drops) with extended GOPs (GOP-size > 15).
10.3.2
encoder 2
encoder 2
is disabled by default.
Note that the
encoder 2
option is dependent on the set frame rate and resolution of
en-
coder 1
.
Select the
encoder 2
tab.
Fig. 10-5
If required, activate the
Use encoder
checkbox to enable Encoder 2.
Select the required settings (see section “
Confirm with
oK
.
10.3.3
encoder 3
encoder 3
is disabled by default.
encoder 3
only supports the encoding standard H.264.
Note that the
encoder 3
option is dependent on the set frame rate and resolution of
en-
coder 2
.
Select the
encoder 3
tab.
