4 Replies Latest reply on Apr 29, 2011 5:39 AM by SmellyMcFarty

    Ignoring but preserving an alpha channel

    SmellyMcFarty

      I'm working with a png sequence that has an alpha channel that holds information for a stereoscopic 3D display process. I do not need the alpha to be viewed but it does need to be rendered with the final movie clip in order to be processed in RAD Tools. Anyway this is possible?

        • 1. Re: Ignoring but preserving an alpha channel
          Colin Brougham Level 6

          Two ways you might do this:

           

          1. Select your PNG sequence clip in the bin, and right-click or go to Clip > Modify > Interpret Footage. Select "Ignore Alpha Channel" in the alpha channel portion of the dialog. When it comes time to export, simply reverse this process.
          2. Use the Alpha Adjust effect (Video Effects > Keying). Apply it, and tick the "Ignore Alpha" option. You could save that as a preset or copy and paste it to other clips. When it comes time to export, select all the clips, and right-click or go to Clip > Remove Effects; check only the "Video Effects" option and hit OK. The caveat is that this will remove all other applied video effects from the selected clips.

           

          Hope either of those accomplish what you need...

          • 2. Re: Ignoring but preserving an alpha channel
            SmellyMcFarty Level 1

            Thanks for the response, unfortunately what ends up happening is that in  the render (either after effects or premiere) the alpha information  ends up cutting pieces out of the video image (which ultimately is it's  proper function). So when I re-import the rendered QT file and ask it to   ignore the alpha, it no longer shows me the full image. I guess to  clarify my request, I need to ask how to render an alpha channel that  is invisible to the final render or some way to reapply the alpha to the  rendered file after a full image has been rendered and exported. Or  maybe there's a way in premiere or after effects to indicate a layer as  an alpha and a layer as video? Or a third party program or plugin that  can embed an alpha channel into an existing render? I know it's a strange request...

            • 3. Re: Ignoring but preserving an alpha channel
              joe bloe premiere Level 5

              What are the import specifications for  files to be processed in RAD Tools?

              • 4. Re: Ignoring but preserving an alpha channel
                SmellyMcFarty Level 1

                Rad can take about any format, stills and video alike with alphas. I think it's the actual software player that can remove the alpha until it's needed.