Why Alpha Channel does not work on my template?

VT_91 wrote on 12/3/2021, 3:43 PM

Hello.
I recently downloaded a template and changed pictures in it.
Then I tried inserting it into a project.
For some reason, when I change the alpha channel to "straight" or "premultiplied" in the original template, the black is treated as transparent.

Yet when I make those settings on my template, rendered or directly imported, the black is still solid black.

Why is this happening?

I would like to include project files if this would help you answer my question, yet the forum does not allow me to upload .7Z archives.

I don't know if this helps.
Zipped two project folders and uploaded to my Google Drive.
https://drive.google.com/file/d/1T_X0lyiYeVV2k824VsS6oDMySaVbl-Nk/view?usp=sharing

Thank you.

 

Update - I may have found the problem.
However I still don't understand why Alpha refuses to recognize my solid (verified using MS paint paintbucket function) black as black.

How do I do masks in the Vegas if I just happen to have a picture with a solid background then?


 

Comments

john_dennis wrote on 12/3/2021, 7:36 PM

@VT_91

"How do I do masks in the Vegas if I just happen to have a picture with a solid background."

Set Compositing Mode to Difference if the background is black or white.

If the background is another color, use the Chroma Keyer fX.

Musicvid wrote on 12/3/2021, 8:24 PM
  1. Setting Media Properties Alpha to Straight or Premultiplied reveals the Source Alpha layer, if present. It does not create an alpha layer in the output (render).
  2. Selecting a Transparency model in the Project Compositing mode creates Alpha in the output (render) only if the output codec supports Alpha, the Alpha settings are enabled (RGBA or YUVA), and Vegas supports Alpha rendering for the chosen codec (not always the case). All three conditions must be met.
  3. Statements #1 and #2 are mutually exclusive.

 

jetdv wrote on 12/4/2021, 7:48 AM

I recently downloaded a template and changed pictures in it.

How did you "change" the pictures and how did you save it after changing the pictures? If you didn't save it in a format that supported alpha channel then you won't have an alpha to show through anymore. Or if the pictures you used as a replacement don't have alpha, then there's no alpha to show through.

VT_91 wrote on 12/4/2021, 4:32 PM

Thank you. Let me experiment with this again, when opportunity arises and I will tell what worked and what did not.