Cobalt Digital COMPASS 9086 Embedded Audio Loudness Processor - Manual (Page 41)

9086-OM (V4.3) 9086-SD PRODUCT MANUAL 3-13
Operating Instructions
9086 Function Submenu List and Descriptions
Audio/Video Sync (Framesync Tab)
Provides video offset and audio re-sync tools.
Note: The 9086 framesync function is mainly intended to provide audio/video resyncing (loudness processing induces an
8 msec delay which can be nulled by advancing the audio 8 msec using the Audio Offset from Video control described
below). When loudness processing is enabled, the glitch-free audio resyncing provided by the audio SRC is not
available. To ensure glitch-free audio resyncing, it is recommended that the incoming video be locked to reference
upstream of this card, and to have the framesync on this card set to the corresponding external reference (Reference 1
or Reference 2).
In this manner, the audio SRC is never called upon by the card processing, while setting this card to also use the
external reference allows the framesync function to provide full Freeze to Last Frame or Freeze to Color protection upon
loss of input. If this protection is required without the incoming video being upstream frame synced and with framesync
enable set to an external reference on this card, hard audio resets (and the resulting audio “hits”) must be expected.
• Framesync Enable Disables the Frame Sync function, or selects from choices below.
• Off: Disables Frame Sync function; output video timing matches the
input video timing.
• Reference 1: Allows Frame Sync function to use external
Reference 1 as the reference standard.
• Reference 2: Allows Frame Sync function to use external
Reference 2 as the reference standard.
Note: If Reference 1 or Reference 2 is selected and an
appropriate external reference is not received, the
indication appears in the Card Info
status portion of DashBoard™, indicating invalid frame sync
reference error. (Additionally, the card edge ERR indicator
illuminates indicating the same.) External reference signals
Reference 1 and Reference 2 are distributed to the card
and other cards via a frame bus.
• Input Video: Uses the input video signal as the
reference standard.
Note: If Input Video is used for framesync, any timing instability
on the input video will result in corresponding instability on
the output video.
• Vertical Delay Control
When Framesync is enabled, sets vertical delay (in number of lines of
output video/timing) between the output video and the frame sync
reference.
(Range is -1124 thru 1124 lines.)
Note: Lines refer to lines in the output video format, and not to the
reference format.
• Horizontal Delay Control
When Framesync is enabled, sets (in µsec of output video timing)
horizontal delay between the output video and the frame sync reference.
(Range is -64.000 thru 64.000 µsec)
Note: When an external framesync reference is used, the card will not
produce a framesync reset until the variance between framesync
reference and output video exceeds ± 2 clock periods. Therefore, a
framesync reset will not result if offsets within this window are
applied.
To apply an offset/framesync reset within this window, first apply a
relatively large offset, then apply the target smaller offset.
Example: To apply a 1-period offset, first apply a 10-period positive
offset and then apply a 9-period negative offset. This results in the
target 1-period offset being applied to the output video.
Table 3-2 9086 Function Submenu List — continued