ATEM - Premultiplied Alpha Reversed?

General
1

Well… I don´t get it…

ATEM Television Studio HD + Ultrastudio HD Mini + Standard Caspar Config for Decklink, Keyer set to external.

When using the Caspar “Test graphic” where it tells you if the key is correct or not, it´s kind of reversed for me…
I activated “premultiplied” in the ATEM DSK. The graphic is telling me “Key incorrect, Straight Alpha not recommend”… if I deactivate the “premultipled” the graphic is telling me it´s correct - but I´m able to adjust gain, etc. parameters what I don´t want, as it should be correct out of Caspar…

Any idea what´s wrong?

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <paths>
    <media-path>media/</media-path>
    <log-path>log/</log-path>
    <data-path>data/</data-path>
    <template-path>template/</template-path>
    <thumbnail-path>thumbnail/</thumbnail-path>
    <font-path>font/</font-path>
  </paths>
  <lock-clear-phrase>secret</lock-clear-phrase>
  <channels>
<channel>
      <video-mode>1080p2500</video-mode>
      <channel-layout>stereo</channel-layout>
      <consumers>
            <decklink>
                <device>1</device>
                <embedded-audio>true</embedded-audio>
                <channel-layout>stereo</channel-layout>
                <latency>normal</latency>
                <keyer>external</keyer>
                <buffer-depth>3</buffer-depth>
            </decklink>
      </consumers>
    </channel>
	  </channels>
  <controllers>
    <tcp>
      <port>5250</port>
      <protocol>AMCP</protocol>
    </tcp>
    <tcp>
      <port>3250</port>
      <protocol>LOG</protocol>
    </tcp>
  </controllers>
<osc>
  <default-port>6250</default-port>
  <predefined-clients>
    <predefined-client>
      <address>127.0.0.1</address>
      <port>7400</port>
    </predefined-client>
    <predefined-client>
      <address>127.0.0.1</address>
      <port>5253</port>
    </predefined-client>
   <predefined-client>
      <address>127.0.0.1</address>
      <port>7401</port>
    </predefined-client>
  </predefined-clients>
</osc>
</configuration>
2

I sometimes also do not undersatnd this test graphic. But what is a good indicator of a correct setting: In the center of that graphic is a White circle with a alpha transparent gradient. When it has a black border, it’s wrong, it should uniformly fade from White to transparent.

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3

Ok, got it. When premultiplied is on, it´s faded out. But graphic says it´s incorrect… weird…

Got some files to check if they are correct or not and was really confused… You know, one of these “days”… :smiley:

4

Maybe it’s meant to make us double or triple check :joy:

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