Brompton TESSERA M2, User Manual, Page: 220 / 296

220
TESSERA - V3.0 | USER M ANUAL - REV B | 14.4 - GENLOCK SETTINGS
N OTE The selected genlock fram e rate affects the capacity of each Tessera output port. See
Output Capacity on page 43 for m ore inform ation.
If the fram e rate of the video input differs from the reference, whether it is internal, another
video input or a bi- level or tri- level sync, the processor will m atch the fram e rate by either
doubling or dropping fram es. For critical synchronisation between two or m ore processors, the
incom ing fram e rate should m atch the referenced fram e rate.
14.4.4 - ACTIVE INPUT GENLOCK
The ‘Active Input’ is selected by default for new projects and switches autom atically to the
genlock source between the HDMI and SDI inputs according to which input is selected as the
active video source. This helps to display video content at the correct fram e rate with the
m inim um latency and avoids fram e drops or doubling due to inadvertently using the wrong
genlock source.
N OTE This is a Tessera SX40 and S8 only feature as Tessera S4 and T1 have only one input,
and the M2 has two video processing pipelines and can crossfade between inputs, so
dynam ically switching the genlock source on these processors is not as desirable.
14.4.5 - GENLOCK PHASE OFFSET
Genlock Phase Offset perm its fine control of the LED screen tim ing to rectify visual artefacts if
present on cam era. Artefacts which m ay appear as dark lines on the LED wall when viewed
through the cam era's electronic viewfinder. Settings should be toggled until less apparent or in
cases com pletely disappear off the top or bottom of the cam era fram e.
N OTE Fine control of cam era shutter speed is typically also required to avoid scan
m ultiplexing causing artefacts on cam era. I.e. Fine shutter speed control on the
cam era is also needed alongside genlock phase offset on the processor to achieve
the best possible results.
An offset of up to plus or m inus one fram e m ay be configured, specified either as a fraction of a
fram e in percent, or a phase angle in degrees, as an absolute num ber of lines and pixels of the
selected genlock source.
Fig 14.5 - Phase Offset options can be found under Network, Genlock. Options available to
offset by are angle, fraction or use an absolute value.