How to stop a transparent clip losing its colours when it is composited
Tell Vizard Agent that the transparent clip also looks wrong in other players. That symptom points away from grading and towards decoding: a file with an alpha channel read by something that ignores it comes back with shifted colours. It inspects the alpha, decodes through a path that handles it, and checks the colour on an actually composited frame.
What do you type into Vizard Agent?
Report the symptom across players, not the colour itself. Saying the clip looks washed out invites a grade; saying it looks the same way in two unrelated players says the file is being read wrongly, which is a different investigation. Send the original transparent files, because a re-export has usually lost the evidence Vizard Agent needs.
Prompt
What does Vizard Agent actually do?
A transparent overlay carries two things: the picture and the mask. Read by the wrong path, the mask gets folded into the picture, and the colours come out subtly and consistently wrong in a way no colour correction fixes. So nothing gets corrected until the decoding question is settled. In the session behind this article it:
- Inspected the alpha channel and the real parameters of a set of overlays that kept coming back discoloured, and checked how the transparency was being extracted.
- Looked at the available ways to decode that format's alpha and tested an alternative decoder on the same frame.
- Decoded correctly, composited onto the intended background and pulled a frame through the alpha-capable path to check.
- Checked that the background was not swallowing the transparent layer, a different failure that also looks like wrong colours.
- Confirmed the colour on the composited result, then rebuilt the edit from the correctly decoded clips.
When does this not work well?
Some files are simply wrong. If the transparency was baked in at export, or the alpha was flattened at some earlier point, there is nothing to decode, and Vizard Agent will say so. Premultiplied and straight alpha need different handling, a format with no alpha at all becomes a keying job, and heavily compressed overlays fringe at the edges regardless.
Common questions
How do I know it is not my grade? It looks wrong in unrelated players too. Vizard Agent starts there.
Can it just correct the colour? Vizard Agent can, but that bakes in a fix that works on one background only.
Why did one player look fine? Because that one handled the alpha and the others did not.