Example: Keying in Warp Mode with Memory Palace v2.0.1-beta

This topic presents an exploration of Memory Palace keyer in Warp Mode as implemented in v2.0.1-beta.

  • LZX Memory Palace
  • LZX Visual Cortex
  • LZX Doorway

FAQ:

  • What configuration of Memory Palace achieves pass through in Warp Mode?

A key of minimum span shows background for any center. From any configuration that shows background only, activating the Invert toggle shows foreground only. This is one method of achieving pass through.

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  • How can an unwanted horizontal offset during keying operation be corrected?

If a discrepancy in horizontal alignment between key edge and source appears during keying operation, power cycling Memory Palace will restore alignment. In some cases, resolution may require power cycling more than once.

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(The Memory Palace used in this Example is running a fresh installation of firmware memorypalace_v2.0.1-beta.zip released 11MAY20.)

Memory Palace: Luma Keyer Control

  • Memory Palace achieves Luma keying through adjustment of Width, Center, and Softness sliders.

  • A still is uploaded to Memory Palace, presented below with annotated Luma values.


Key Mode, Luma: Hard Keying

  • The Center slider selects a foreground Luma value as key target. The Width slider adjusts the span of the key target around center. In Warp Mode, Luma values outside of the key target span reveal the frame buffer as background. The slider configuration below targets 40% luma values through adjustment of Center slider to 50% and adjustment of Width slider near 10%.


(Note: The Softness slider is set to 0% and as such characterizes a hard key.)

  • Activation of the Invert Toggle changes keyer behavior by switching the relationship of foreground and background. In this configuration, keying now reveals background in place of foreground.


A side by side comparison of Invert toggle behavior can be appreciated below.

  • When Invert is inactive, the key target shows FG, and Luma values outside of target span show BG.

  • When Invert is active, the key target shows BG, and Luma values outside of target span show FG.

  • The following reference presents a hard key as established by Memory Palace in Luma mode with center point indicated by arrow and width represented as increasing span.


Key Mode, Luma: Soft Keying

  • A still is uploaded to Memory Palace, presented below with Luma reference.

  • The Softness slider controls key edge softness from 0% (hard) to 100% (soft.)
  • A 50% Luma key is established and adjustment of Softness during 0-80% sweep is appreciated as .gif below.

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  • Adjustment of Softness in 80-100% range follows.

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  • To change the behavior of this slider, the default S-Curve setting is changed from Heavy to Light via the Softness Parameter menu.

  • Adjustment of Softness (S-Curve: Light) during 0-80% sweep is appreciated as .gif below.

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  • Adjustment of Softness in 80-100% range follows.

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(Note: The current functionality of the Softness slider may be malfunctioning however it does well if you believe in yourself and move the slider in small increments within the 80-100% range.)


Key Mode, Chroma

  • A still is uploaded to Memory Palace, presented below as signage over bars.

  • With Width, Center, and Softness sliders set to 0%, Memory Palace outputs the following result.


  • 0-100% sweep of Width slider appreciated below as .gif.

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  • 0-100-0% sweep of Center slider appreciated below as .gif.

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  • A few combinations of Width and Center are presented for consideration below.
  • First, a key of minimum span has its center adjusted from 0-100%.

  • Second, a key of median span has its center adjusted from 0-100%.

  • Last, a key of maximum span has its center adjusted from 0-100%.


(Note: The current functionality of chroma keying may be malfunctioning however anything is possible if you believe in yourself and perhaps it will be improved in a forthcoming firmware update.)


Key Mode, Alpha

  • A key is prepared as alpha input to Memory Palace to be used as alpha key source. (VC, H+V Ramp > Doorway > MP Alpha IN)

  • Memory Palace Alpha IN is keyer source.
  • Aux Mode, Alpha: Aux channel is summed with the alpha input, providing a secondary alpha input and opacity control.


  • As in other modes, activation of the Invert Toggle changes keyer behavior by switching the relationship of foreground and background. In this configuration, keying now reveals background in place of foreground, presented below followed by slider adjustment.

  • A 1V signal is output to AUX input.

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  • The AUX input is summed with the alpha input.

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  • When Alpha keying in Media mode, the alpha channel of the loaded still is used as key source.

TLDR:

  • Effective keying with Memory Palace begins with identifying how a key of a given width and center interacts with different keying modes.

8 Likes

Excellent breakdown of the Memory Palace keyer. :medal_sports:

I was wondering if I was missing something… then I got to this wonderful nugget

( Note: The current functionality of chroma keying may be malfunctioning however anything is possible if you believe in yourself and perhaps it will be improved in a forthcoming firmware update.)

Thanks for doing these. Your documentation and clarity is fantastic. Looking forward to seeing more.

2 Likes