2019 version doesn't render clips with alpha channels as transparent

[MaxAppian]

I have a timeline that contains some rendered out clips with alpha channels over video (titles and such).  In the timeline everything looks good.  When I render it out, the clips with alpha channels do NOT render out as transparent- they have the black backgrounds. 

[getho]

so to clarify: this should now be working as it was before?  No need to turn off maximum bit depth??

Because in the most recent (as of july 2019) version I still dont get an alpha chanell in cineform 12 bit with alpha export.

[Carlos Ziade]

DaveAtNeoti​ you don't have to select each clip separately to modify it from the project panel, you can simply select all by pressing CTRL+A then right click on any of them, choose Modify - Interpret Footage.

Selecting the Sequence won't interpret footage. Select all cips then holding CTRL you can deselect the sequence and other assets that you don't want to modify. You can also put the clips you want to modify in a separate bin.

What format are you using for export ? Better go for Quick Time GOPro Cineform YUV 10 bit, then use that exported clip to make other formats out of it. Let me know the results please

[Guest]

I'm having the same issues. I've tried exporting to multiple formats in both the Media Encoder queue and directly from Premiere. If I do a quick still export of a frame, it works fine, but I can't get a video to output with the alpha channel transparency working.

[REZI]

I've noticed premiere 2019 blacking out alpha if.... 1. Export settings have render at maximum depth selected, and or 2. Sequence settings have Maximum Bit Depth selected.... Simply deselect these... It worked on mine... In previous versions having these selected  didn't black out alpha.

[Carlos Ziade]

adobe100000000​ you seem to be on software only, can you please confirm this ?

[REZI]

Nope in the Mercury Playback open cl

[Carlos Ziade]

adobe100000000​ can you please try to switch to Metal ? and reply back ?

[Ann Bens]

BTW prores 422 does not support Alpha channel.

Use proress 4444 with alpha channel selected or

Animation or

Cineform 12 bit with alpha.

[Carlos Ziade]

Hi Ann, the issue here is that the user does not want to export a video with alpha channel, they already have videos with alpha channel composited upon other videos, so they simply want the export to show the underlying video already on the timeline, that which is not happening. I would agree with you if you have a video that you want to export with its alpha channel as a video with transparent background

[REZI]

Metal behaved the same on the alpha clips as Open Cl saw no difference.

[Carlos Ziade]

adobe100000000​ thanks for your cooperation, can you please share your system specs? Im interested to know more about your MacOSx version

[REZI]

[Carlos Ziade]

adobe100000000​ thanks for your help, if you have time, can you please try to modify your clips from the project panel and set Alpha Channel to and don't check premultiplied alpha ?

try also checking premultiplied alpha to test what's happening in your case, this would be useful to other users

[REZI]

When unchecked the subtle lighting from the transition is gone...

premultiplied alpha Not Checked

premultiplied alpha Checked (below)

USE ALPHA FROM FILE (below)

[Carlos Ziade]

tx a lot for sharing, these are export results or timeline results ?

[REZI]

Screen Grabs from timeline

[Carlos Ziade]

so before you were getting black results ?

can you try to export the setting that looks best ? to make sure alpha is exported correctly ?

[REZI]

Before it looked like this.... Couldn't see the image underneath. But once I unchecked maximum bit depth in both sequence and export settings. It acted correctly (as seen in previous response)  in both timeline and x-ports.

[Carlos Ziade]

Please keep maximum bit depth checked in both, and try the results with modified Alpha Channel set to (premultiplied checked, and uchecked, try both) try the same procedure as before, but now with Maximum bit depth checked, can you do this ?

[REZI]

Doesn't work. Just comes out with black video underneath.

I got to go. Hope this helped.

[AlexManni]

Alright, just tried it - still not working. When Maximum Bit Depth is checked - it is not rendering the transparency in the Alpha clip.

[Carlos Ziade]

try Cineform 12 bit with Alpha as Ann suggested before, does this make any difference ?

[Carlos Ziade]

Also please check this thread and read Neil Haugen's post number 5 and find out if you really need to render and export at maximum bit rate and maximum bit depth even with alpha channel :

"Use Maximum Render Quality" for Youtube ..?

[AlexManni]

Having the exact same problem. I have a ProRes 4444 w/ Alpha Channel clip on top of my timeline and when trying to export/render with Maximum Bit Depth it's exporting with no transparency. All transparent areas are black.

This has to get fixed fast - or there's a swarm coming.

[Ann Bens]

Exporting to what? Post export settings.