Cobalt Digital COMPASS 9033 Input Processing Analog to Digital Video - Manual (Page 14)

1
9033 Functional Description
1-10 9033 PRODUCT MANUAL 9033-OM (V4.0)
Figure 1-4 Audio Mono Mix Functional Block Diagram with Example Sources
2.0-to-5.1 Upmix Function
Note: Upmix function is an optional licensable feature. This function and its controls
appear only when a license key is entered and activated. (This option (identi-
fied in Cobalt
® price lists as +UM) can be purchased upon initial order, or
field-activated using a key string which is sent to you when this option is pur-
chased.)
The 2.0-to-5.1 upmixer function receives a normal PCM stereo pair from the
Audio Routing/Gain Control function and upmixes the pair to provide 5.1
channels (Left (
L ), Right ( R ), Center ( C ), Low Frequency Effects ( LFE ), Left
Surround ( Ls ), and Right Surround ( Rs )). Whenever the upmixer is active, it
overwrites the six selected channels with the new 5.1 upmix signals
(including replacing the original source stereo
L and R inputs with new L and
R signals).
The 2.0-to-5.1 upmixer can be set to up mix in any of three modes: Always
upmix, Bypass upmix, or Auto enable/bypass upmixing. The Auto upmixing
mode looks at the signal levels on the selected channels and compares them to
a selectable level threshold. It then determines whether or not to generate 5.1
upmixing from the stereo pair as follows:
• If the upmixer detects signal level below a selected threshold on all
four of the selected channels designated as
C , LFE , Ls , and Rs , this
indicates to the upmixer that these channels are not carrying 5.1. In
this case, the upmixer overwrites all six selected channels with the
new 5.1 content.
• If the upmixer detects signal level above a selected threshold on any
of the four selected channels designated as
C , LFE , Ls , and Rs , this
indicates to the upmixer that the channel(s) are already carrying
viable 5.1 content. In this case, the upmixer is bypassed, allowing the
original channels to pass unaffected.
MONO L
Σ
R
AES Ch 12
AES Ch 16
AES Ch 1 - Ch 16
AN-AUD Ch 1- Ch 8