Parameter Values Description
Language A selection of languages from across the world. The language of the stream to be signaled in descriptors.
Audio Stream Type
Main Audio; Clean Effects; Hearing Impaired;
Visual Impaired
Intended use of the audio.
MPEG Version MPEG-1; MPEG-2 Standard to be used for the output compressed audio.
Copyright Off; On Set the copyright bits in the MPEG headers.
Original Off; On Set the original bits in the MPEG headers.
De-emphasis Off; 50/15us; CCITT J.17
Set de-emphasis as applied to the audio, in the MPEG
headers. Does not apply the appropriate pre-emphasis.
Action on control track
loss
No action; Bit rate saving
If Bit rate Saving is selected, there shall be no emitted
elementary stream for Audio Description if the control track
is not received.
Action when silence is
detected
No action; Bit rate saving
If Bit rate Saving is selected, there shall be no emitted
elementary stream for Audio Description if silence is
detected on the incoming audio track.
Silence Threshold Decibels, -90 to -1, dBFS
Threshold of incoming audio track, which, if below the
threshold will be determined to be silence.
Silence Period Time, seconds, 0-300
Duration of silence as determined by the threshold,
needed before Action when Silence is Detected will take
place.
Table 5.24 Automatic Loudness Control Parameters
Parameter Values Description
Operating Mode Off ALC is not in use.
Measure
Long and short measurements are taken and displayed in
the status but no audio adjustments are made.
Measure + ALC
Measurements are taken and corrections are made for
short term peak in audio that are measured 1 LU above
the Target level.
Measure + ALC + LTLC
Measurements are taken and corrections are made for
short term peak in audio that are measured 1 LU above
the Target level. Corrections are also made over the
longer term to adjust the channel loudness level to that of
the Target Level.
In this mode manual gain adjustment from the codec page
is disabled.
Target Level -40 to 0 (LKFS (LU) The desired Loudness level for the channel.
Time Period 5 to 120 minutes
This controls the responsiveness of the long term audio
loudness level correction.
A smaller number will result in the audio being adjusted
more dynamically. A larger value will give a slower less
noticeable adjustment.
Peak Limit -20 to 0 dBFS
This controls a hard clipping limiter for the audio level.
This adjustment is based on the absolute peak level
measured in dBFS.
The peak limiter only operates in ‘Measure + ALC’ and
‘Measure + ALC + LTLC’ modes.
If this value is set to 0 no limiting is performed
To Next Page
Loading...
