Tektronix 2200 Manual Do Utilizador

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Section 3 — Functional Description
The incoming video and keys from the Crosspoint Module are first 
converted from serial to parallel. Next, there are selectors that select 
between the Chroma Keyer and the Crosspoint Module. The selected video 
and key are then sent to the Keyer Mezzanine Modules. 
Parallel video from the Keyer Mezzanine Module to the Keyer Carrier 
Module are: 
A clipped, gained and masked key and a shaped video for the 
background
A clipped, gained and masked key and a shaped video for the key 
If there is a BORDERLINE Mezzanine installed, the key goes onto that 
module and has a border added to it. The BORDERLINE Mezzanine is 
described later in this section. 
Next, there is a a Non-Additive Mixer (NAM) in the key path. The NAM 
can do a mix between the two keys of that M/E. The key NAM compares 
the luminance level of Key 1 and Key 2 fills and puts the key that has the 
highest instantaneous luminance level of its fill on the air. Only the NAM 
on the A keyer for each M/E is active. The video and key from the B keyer 
is sent to the A keyer for NAMing. 
The outputs of the Keyer Carrier Module are parallel video. The A video 
and keys are sent to the Mixer Interface Module, the B video is sent to the 
Mixer Module. 
Keyer Mezzanine (064826) 
There are two Keyer Mezzanines on each of the Key Carrier Module. One 
Keyer Mezzanine is for a background layer and the second Keyer 
Mezzanine is for the key layer. Backgrounds can be used as keys in the 
“Layered Mode.” 
On the Keyer Mezzanine Module the video is separated into luminance 
and chroma. All videos are timed together and all keys are timed together. 
Depending on control panel settings, the video then goes through 
processing for gain and offset and coring for noise reduction. Depending 
on settings, the key is clipped and gain adjusted, and the video is shaped 
by its key. Masks are added, then the signal goes off the keyer Mezzanine 
Module and back to the Keyer Carrier Module.