I've always told After Effects artists etc... the Avid can only handle a straight Alpha. That was true in the past but is it still true? Today I clicked on the effects window of an imported matte key graphic and I accidentally hit the Foreground carrot and it opened to reveal a check box for premultiplied foreground. I had not noticed this before. I'm assuming that means Avid can now accept a premulitplied graphic as well as a straight graphic. Is this a valid assumption?
Back in the day GVG called key inputs shaped or unshaped for inputs that were premultiplie and straight. Prior to that on a GVG they had regular key and linear key that allowed for a feathered key. I've always considered premultiplied vs. straight in the same way I though of the switcher configurations. Chyrons were straight but Dubners and others could be shaped although I only worked with Chyrons at that time. Similarly the Devious/Gevious IIRC could work either way. I forget the menu settings as the Devious was properly named when trying to figure it out.
My curiosity is when did Avid add the foreground Premultiplied checkbox and if the foreground is premultiplied does that mean the key/alpha channel is not straight. I always think of the two going hand and hand or Fill to Key if you will.
John Moore Barking Trout Productions Studio City, CA bigfish@pacbell.net
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