DMG 3200/3100/3000 – User Manual
Page 235 (306)
8.7 Statistical Multiplexing
The principle of statistical multiplexing is that a group of video encoders/transcoders (referred to
as a StatMux group) shares a fixed quantity of TS bandwidth. The bandwidth is distributed by a
centralized StatMux controller, and the program with the most complex video may be allowed to
use more bandwidth than programs with less complex video or with a lower priority.
The statistical probability that all programs in a multiplex shall demand a high bit rate at the
exact same time decreases when the size of the multiplex group increases.
The motivation for a StatMux system is to either:
• Avoid spending bandwidth on simple video sequences in order to free up capacity for
new programs in the multiplex.
• Distribute available multiplex bandwidth between programs in order to increase overall
video quality (VQ), by minimizing overall quantization (QP)
8.7.1 Modules Supported
The StatMux controller is located on the MMI module of the unit. This is responsible for the
control of the StatMux groups and modules.
The following encoder/transcoder modules types are supported:
• encoder-hd (Dual HD-SDI encoder)
• encoder-hd (Dual HD-SDI encoder with AES )
• encoder-sd (QUAD SD-SDI encoder)
• transcoder-hd (HD transcoder)
• transcoder-sd (SD transcoder)
8.7.2 Statmux group configuration
The Statmux tab is available under the top level Coders menu, below all encoders/transcoders.
Clicking the Statmux tab will bring up the StatMux GUI page. This is where the StatMux groups
are generated. On this page, the encoder and transcoder modules are listed on the left hand
side, under Coder Inputs. All Statmux groups are listed on the right hand side, under StatMux
Output.