Cobalt Digital COMPASS 9822 Downconverter - Manual (Page 11)

9822-OM (V4.1) 9822 PRODUCT MANUAL 1-7
Introduction
9822 Functional Description
A video/audio delay offset function allows adding or reducing audio delay
from the matching video delay. This function is useful for correcting lip sync
problems when video and audio paths in the chain experience differing
overall delays. A Reset Framesync function resets the frame sync following
any horizontal or vertical offset changes, clearing any buffered audio and
video and re-establishing the frame sync. The 9822 re-establishes video/audio
sync following framesync changes by applying an offset in small, progressive
amounts to provide a seamless, glitch-free retiming. A user-selectable hard
resync function allows setting a threshold at which hard resync is applied if
audio-video offset exceeds the threshold. Hard resync provides fastest
snyc-up suitable for off-air manipulation. Conversely, a threshold setting that
avoids hard resync allows glitch-free on-air manipulation.
In the event of input video loss of signal, this function provides for disabling
the video, going to a desired color raster, or freezing to the last intact frame
(frame having valid SAV and EAV codes).
Downconverter Function
The downconverter function provides down-conversion from multiple
standard HD video formats to corresponding NTSC or PAL SD interlaced
formats. Table 1-1 lists the 9822 conversion choices available for various
input formats and frame rates.
Note: “NTSC” and “PAL” in this manual respectively denote 525i5994 and 625i50
SD-SDI, and are not meant to denote in any way NTSC or PAL analog for-
mats.
The downconverter function also provides aspect ratio conversion that
provides a choice from several standard aspect ratios. Additionally, user
defined and “Follow AFD Settings” conversion can be applied. User defined
settings allow custom user-defined H and V aspect ratio control. “Follow
AFD Settings” sets the output aspect ratio to track with AFD (Active Format
Description) settings embedded in the video signal.
Table 1-1 Downconverter Function Conversions
Input
Format
SD Output
Format
(NTSC/PAL)
Input
Format
SD Output
Format
(NTSC/PAL)
Input
Format
SD Output
Format
(NTSC/PAL)
525i 59.94 525i 59.94 720p 25 625i 50 1080p 29.97 525i 59.94
625i 50 625i 50 720p 24 X 1080p 25 625i 50
720p 60 X 720p 23.98 525i 59.94 1080p 24 X
720p 59.94 525i 59.94 1080i 60 X 1080p 23.98 525i 59.94
720p 50 625i 50 1080i 59.94 525i 59.94 1080PsF 24 X
720p 30 X 1080i 50 625i 50 1080PsF 23.98 525i 59.94
720p 29.97 525i 59.94 1080p 30 X
Notes: 1. “X” denotes conversions not available or invalid conversions.
2. Interlaced formats rates listed are field rates. Progressive format rates listed are frame rates.