No alpha transparency for compound clips

Hi everyone.

When Davinci Resolve Beta 15 came out, one of the features listed that compound clips now support transparency. But when I create a compound clip with two or more tracks, background goes black, no alpha at all. What's the problem there? This really is a deal breaker.

I don't know, maybe there's some extra step I'm missing? I really appreciate any help.

[Peter Chamberlain]

Are you on beta 6?

Hi everyone.

When Davinci Resolve Beta 15 came out, one of the features listed that compound clips now support transparency. But when I create a compound clip with two or more tracks, background goes black, no alpha at all. What's the problem there? This really is a deal breaker.

I don't know, maybe there's some extra step I'm missing? I really appreciate any help.

Works fine here. What exactly are you trying to do. Resolve treats the last clip as a background clip, If you combine the two the one below will be treated as a background and alpha is added over and above it and so you will loose the alpha if you try to merge the two alphas of the title clip. A workaround is to link the clips and apply transformations. On the other hand, now that Fusion is part of resolve, I would use it for more complex composites. Having Fusion is like WOW for us here, hardly a deal breaker.

But when I create a compound clip with two or more tracks, background goes black, no alpha at all.

This is the key here. I am assuming what you are trying to do is to compound multiple clips that have transparency over a background, right?

If that is the case, then it still doesn't work in Resolve. Compound clips can only take one clip with an alpha channel. The moment you add multiple ones there, it breaks.

However, there is still a solution for you. As Rajiv said, you can use Fusion clips instead of compound clips. Since Fusion is an advanced compositor, it can easily handle multiple alpha channels merged together and send that back to the Edit page.

Are you on beta 6?

@Peter, I am not sure about the OP, but I am on beta 6 and this still happens.

The issue is exactly as Abdelrahman describes. When I create a compound clip with more than one clip (say a title and a png image) transparency is lost. I really don't see the point of supporting alpha if can't do it with multiple clips, because having multiple clips is the whole point of compound clips, no?

Anyway, thank you all for your replies.

Same here.



Tested on Beta 6.

Same here.



Tested on Beta 6.

I prefer to go in the tab Fusion: it is more powerful than the compound clip which is not powerful enough in a lot of cases.
It is humbly my opinion.

Sometimes you are doing something in Edit with multi layers and resizing or a graphic with alpha, and at a later stage decide to do something to it using Fusion. It is a waste of time to have to re-create whatever you did in Edit to work around this Alpha limitation. IMO Fusion should handle any and all Edit's output just as Edit displays it.
tx
Mark.

Just searched an hour for what I did wrong before I stumbled across this. Compound looses alpha when two layered clips have alpha?! Come on Blackmagic. You cant be serious. Even my smartphone vid editor can handle that...

viewtopic.php?f=21&t=110358

Some other problem brought me back to exactly this question. It seems that maybe the codec is the culprit. Tried to export with DNxHR HQX 12-bit, alpha enabled and the "individual clips" checked. Gave me no alpha. Tried again with Cineform and that seemed to work just fine. So it seems that compound clips can have alpha. Can anyone confirm this?

Works perfectly for me, no issues at all.
DNxHR must be a "444" type to include alpha channel.

Just searched an hour for what I did wrong before I stumbled across this. Compound looses alpha when two layered clips have alpha?! Come on Blackmagic. You cant be serious. Even my smartphone vid editor can handle that...

For me working very well with Compound Clip (ver 16.2).

Works perfectly for me, no issues at all.
DNxHR must be a "444" type to include alpha channel.

I usually export DNxHQX with alpha (MXF container).

Also having this issue in 16.2.2.011

Same here. Lose alpha if putting 2 or more clips together in a compound clip.

i recognize this, was happening not too long ago , but i cannot reproduce it for some reason.

Hi all

I'm having this issue, I think, in 16.2.2.012.

However I have it both with CCs and with nested Timelines. Does that match the issue that you guys are having?

Here's an example:


Lower timeline shows a Timeline (not CC), containing several media clips, with an adjustment clip on the top. The adjustment clip has a Fusion DeltaKey effect applied, to cut the subject out of the background and replace it with transparency. This appears to work fine when viewed in Fusion - MediaOut shows the transparency background grid.

But when this timeline is nested in another timeline, as seen in the top viewer in above screenshot, I do not get any alpha. So in the top timeline above, only the output of Video 2 is shown; Video 1 is not overlaid underneath.

This is really frustrating because I hoped to simplify my green screening - which I need to do across 33 different clips, with three different configurations - by applying it in bulk in timelines or CCs that I would then nest.

I can get it to work if I apply the DeltaKey to every individual media clip in a given timeline, but that's so much messier.

I don't know how to start a new thread here. Apologies for hijacking.

I have a roughly related issue. To be brief:

When saving fusion clip as PNG still with alpha, it is impossible to export with Resolve FX nodes applied and clean Alpha at the same time. Resolve FX disappear from the final PNG still with FX Alpha channel OFF. Or I toggle the Resolve FX Alphas ON, but the background is black (or semi-trans black in this case due to blend node being at a %).
Works fine when I render an Alpha applied .mov

Many thanks for any help.