Table of Contents
Advertisement
7700 MultiFrame Manual
7735CEM Composite Encoder with Monitoring
7.10.6. Detecting Audio Silence Faults
The Silence level and Silence duration controls are used to detect when the audio is considered to be
silent. The Silence level control sets the audio level under which the audio is considered to be silent. The
audio must be under the Silence level for the duration set by the Silence duration control before the fault
condition exists. When the fault condition exists, the audio must be over the Silence level for the duration
set by the Silence duration control before the fault condition will be removed. A fault will be generated
when both channels in a pair (1 and 2 or 3 and 4) has satisfied a silence condition.
7.10.6.1. Setting the Audio Silence Level
Fault definitions
Silence level
-96dB to –20dB FS
-60dB FS
7.10.6.2. Setting the Audio Silence Duration
Fault definitions
Silence duration
0.5 to 127 sec
10 sec
7.10.7. Detecting Audio Phase Reversal Faults
All stereo audio material has a varying amount of phase difference between the two channels. If there is
significant phase reversal for a period of time, then this is a sign that the audio signals may be out of
phase.
The Phase reversal level and Phase reversal duration controls are used to detect when the left and right
audio channels are considered to be out of phase. The Phase reversal level control sets the amount of
phase difference that is considered to be out of phase. The audio must be out of phase by more than the
Phase reversal level amount for the duration set by the Phase reversal duration control before the fault
condition exists. When the fault condition is active, the audio must be out of phase by less than the Phase
reversal level amount for the duration set by the Phase reversal duration control before the fault condition
will be removed.
7.10.7.1. Setting the Audio Phase Reversal Level
Fault definitions
Phase reversal level
0.5 to 1 in 0.01
increments
0.9
7735CEM-48
Gray background indicate un-implemented or un-tested features
This control sets the audio level under which it is considered to be
silent. This value is expressed in dB full scale (FS).
This control sets the amount of time the audio is silent in seconds
before a fault occurs.
This control sets the amount of phase difference before the audio is
considered to be out of phase. This phase reversal is calculated by
comparing the difference of the two channels to the average of the two.
If a signal is always out of phase, then the difference between the two
will be high compared to the average of the two. This corresponds to 1
in this control.
If there is only content on one of the channels (i.e. left only or right
only), then the difference is equivalent to the average of the two
channels. This corresponds to 0.5 in this control.
Revision 1.1.1
Advertisement
Table of Contents
