Example: Screen blending with Visual Cortex System

This topic presents an introduction to screen blending as achieved in a Visual Cortex System. I will use the following modules along with two external video sources:

  • LZX Visual Cortex
  • LZX Marble Index
  • LZX Bridge
  • LZX Doorway

FAQ:

  • Do I need all of these modules to benefit from this thread?

No, there are a variety of ways to achieve screen blending. This thread hopes to assist in development of screen blending comprehension and proficiency through exhibition.

  • Do I need to understand formulas such as ‘NEG / Negative is OUT = 1.0V - INPUT’ to benefit from this thread?

No, if successful this thread should provide clarity through visual identification of concepts without relying on key terms or underlying theory. With this in mind, remarks have been minimized.


  • The following diagram suggests a signal flow that facilitates distribution of two decoded RGB signals.


NEG / Negative is OUT = 1.0V - INPUT

  • Logotype > VC1 Y OUT > Video Mixer Channel 2 (Framed in Red)
  • Footage > VC2 Y OUT > Video Mixer Channel 4 (Framed in Green)
  • NEG / Negative is OUT = 1 - INPUT

  • Logotype > VC1 Composite OUT > Video Mixer Channel 1 (Framed in Red)
  • Footage > VC2 Composite OUT > Video Mixer Channel 3 (Framed in Green)
  • NEG is VC_OUT = 1 - VC_INPUT


  • NEG is R_OUT = 1 - R_INPUT
  • NEG is G_OUT = 1 - G_INPUT
  • NEG is B_OUT = 1 - B_INPUT


  • Marble Index in FADE mode, followed by BG NEG, Opacity Ch. A 100%, and Ch. A NEG.
  • FADE mode is OUT = (OPACITY * ChA) + ((1 - OPACITY) * BG)





MULTIPLY is OUT = BG * A

  • Marble Index in FADE mode, followed by Opacity Ch. A 100%, and Ch. A blend mode switch set to Multiply.
  • MULTIPLY is OUT = (BG * ChA) + ((1 - ChA) * OPACITY)



  • Multiply is appreciated during Opacity Ch. A sweep.

ChA-opacitysweep

  • A sheet provides reference for combinations of NEG per BG/ChA/OUT, Opacity Ch. A 0/100%, and Multiply.


ADDITIVE is OUT = BG + A

  • Marble Index in FADE mode, followed by Opacity Ch. A 100%, and Ch. A blend mode switch set to Additive.
  • ADDITIVE is OUT = BG + (( - ChA(1 - OPACITY)) + (ChA * OPACITY))



  • Additive is appreciated during Opacity Ch. A sweep.

ChA-additive-opacitysweep

  • A sheet provides reference for combinations of NEG per BG/ChA/OUT, Opacity Ch. A 0/100%, and Additive.


Opacity VC

  • A key is generated.

  • This key is output to Marble Index Opacity VC input, below as .gif.

ChA-opacityvcinput

  • Opacity control is appreciated during Opacity Ch. A sweep.

MIX_442s

  • The key as Opacity control presents below at landmark positions of Opacity Ch. A adjustment.


TLDR:

  • Proficiency in screen blending allows for conscientious and logical composition of assets within the system.



References:

6 Likes

This is such a good demonstration of how these concepts work on MI & Doorway. Solid work.

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