Skip to main content
G
gaston5
Participant
May 13, 2020
Question

Transparency

  • May 13, 2020
  • 2 replies
  • 400 views

Hello!

I have a video that I want to render with a transparent background. I have masked out an object from another video and can in this project use it in any way i like. I would like to have this freedom with the object in any project i would like so I want to render it as a video, but I can't seem to render it with a transparent background. I have tried to export it with rgb + alpha enabled and everything else except of the video disabled, but the video has a black background when rendered. I have also tried to export it to photoshop but when rendered there I get the transparency I wanted but it has an outline of white which I don't want.

 

Any help at this point would be greatly appreciated!

 

This topic has been closed for replies.

2 replies

R
Community Expert
Rick GerardCommunity Expert
Community Expert
May 13, 2020

If your video really has transparency and you verified that by enabling the transparency grid or by checking the Alpha Channel in the Comp Panel, or by checking the Alpha Channel values in the Info Panel and finding zero somewhere in the comp panel, then your comp has transparency. If you were using the Output Module in the Render Cue and you chose the Lossless with Alpha preset then you have a video with an alpha channel. If you created custom settings in the Output Module and you were able to select RGB + Alpha then you have chosen a codec that supports alpha channels. 

Did you notice in this custom setting that I chose Straight Alpha? If so, that is preferred in almost every case because all NLE's and compositing apps work natively with straight alpha channels and pre-multiplying can introduce color to the edges if you have changed the Comp background color. I have been trying to get Adobe to change the default for years. 

 

Open any video with an alpha channel in any media player and you will see a black background. Open a video with an alpha channel in Premiere Pro, After Effects, DaVinci Resolve, Final Cut, Vegas - and the preview will probably show a black background unless you have enabled transparency in previews, but the alpha channel and the transparency will be there. Check the Project Panel. 

If you rendered with a video with RGB + Alpha selected in the output module then the info in the Project panel will show what kind of alpha (Straight or Pre-Multiplied) the video has, but if you did not verify transparency using one of the methods I listed, there is no guarantee there will be transparent areas in the video. 

Martin_Ritter
Martin_Ritter
Legend
May 13, 2020

To do so, you need to set the export to rgb+alpha - just as you already did. BUT you also need a video codec which can handle alpha channel!

DNxHD/DNxHR can do it, as well as ProRes. You can try uncompressed AVI, too, but I'm not sure about it and it will create an insane huge file.

I usualy use PNG image sequence (Tiff will also do it). The downside of this are hundreds or thousend of files, which take forever to copy.

 

*Martin

Terms & ConditionsAccessibility statement
Using the community Terms of use Privacy Cookie preferences Do not sell or share my personal information ad choicesAdChoices