TANDBERG E5714 - Manual (Page 117)

Operating the Equipment Locally
Instruction Manual: evolution 5000 E57xx DSNG and DENG Voyager Encoder Page 4-39
ST.TM.E10076.3
It is possible to operate the Encoder in a stand-alone Variable Bit-rate
(VBR) mode. When in this mode the bit-rate generated by the video
encoder ranges between a minimum (Bmin - dependent on Compression
Mode) and a maximum (Bmax - set by user, up to a limit defined by the
Compression Mode). The video encoder attempts to use a bit-rate to
achieve a particular picture quality set by the user.
If this is set very high then the generated bit-rate clips at the Bmax value.
If it is set very low then the bit-rate clips at Bmin. Somewhere in-between
the bit-rate varies, depending on the picture material being encoded.
Simple pictures use a lower bit-rate than complex pictures.
When in this mode the main encoder output remains at the bit-rate set
within the Mux menu and any spare unused bit-rate is filled with stuffing
packets. These could optionally be removed and reinserted by some
equipment between the Encoder and Decoder.
A typical view of the Video Encoder menu would be:
To run in VBR mode the Encoder must be placed into a Seamless
Compression mode.
A new menu item VBR Mode then appears. When set to Off (Constant)
the Encoder generates a fixed constant bit-rate set by the Bit-rate option.
When changed to On (Variable) the Encoder enters its stand-alone
VBR Mode.
A new menu item appears Max (VBR) Bit-rate. This is the maximum
bit-rate the Encoder will generate. The read-only menu item Bit-rate
remains, but now indicates the bit-rate being generated by the Encoder.