Audio Lkfs Monitor Description; Dolby Digital (Ac-3) Encoder Description (+Encd Only) - Cobalt Digital Inc 9083 Product Manual

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Audio LKFS Monitor Description

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Dolby Digital (AC-3) Encoder Description (+ENCD only)
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Note: Refer to Appendix A, "Loudness Measurement Guidelines and Techniques"
for more information about LKFS parameters and this function, as well as
practical measurement techniques.
This function monitors selected output ("destination") channels from the
Audio Routing/Gain Control function and applies signal analysis based on
ITU-R BS.1770-1 – ATSC A/85 criteria to produce an LKFS measurement
and provide indications of under-threshold and over-threshold level
conditions.
The function can monitor any combination of embedded, AES, or analog
channels (or channels fed to the Dolby
and Rs ITU-R BS.1770-1 channels (note that the LFE and AUX channels are
not included in any LKFS calculations). Because the LKFS monitor uses
output (post-processed "destination") channels, LKFS under/over conditions
can be corrected using the Dashboard™ controls on this card for the
monitored channels (Dolby
Dolby encoder inputs).
The functions provides a configurable moving average period for tailoring the
measurement to suit various program material conditions, as well as
configurable thresholds which provide an unambiguous alarm indication if
the measured LKFS deviates from the thresholds. This function uses the
encoder metadata dialnorm setting as the LKFS target reference.
(See Figure 1-7.) The Dolby
different audio sources (
Routing/Control and produces an encoded Dolby
external metadata or internally generated metadata that can be user-defined
using the encoder controls. The encoded pair can be sent from the card as
embedded audio or over discrete AES-3id connections as a SMPTE
337M-formatted non-PCM signal.
Note: On cards equipped with a Rear I/O Module accommodating AES OUT pairs
5-8, the encoded pair is available as copies on AES channels 9 thru 16.
Input Audio Mapping
Any audio input supported by the card can serve as audio inputs for the
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Dolby Digital (AC-3) Encoder. The six user-selected audio sources are
mapped to
Encr Ch 1
Encode function.
9083 (WITH DOLBY ENCODING OPTION) PRODUCT MANUAL
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encoder) selected as the L, R, C, Ls,
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channel selections use the channels routed to the
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Digital (AC-3) Encoder receives up to six
thru
Input Audio IN 1
thru , which are then fed to the Dolby
Encr Ch 6
9083 Functional Description
) from the card Audio
IN 6
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pair using either received
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9083-ENC-OM (V4.4)
Audio