Alpha gone in Compound and Fusion clips

Hello,

Let me explain what I am trying to do:
I have several .png-s with transparent backgrounds. Out of these .png-s I would like to create animations, by connecting them together with video transitions (eg.: smooth cut).
These animations will be needed throughout the video so I need to repeat them.

So I am creating an animation sequence and I would liek to store such sequences in Compound of fusion clips. However, whenever a Video Transition begins in a Compound clip, the transparency disappears, and everything turns black behind the .png.

I know I could key out the blackness, but since I am working with black objects as well, and there are several of these animations - is there a way to get rid of the non-transparent backgrounds while the video transition is happening?

I'm using Resolve 16 (free) for the record.

Edit: Use case for instance would be: I have a static background and I am trying to animate certain things on it. Like a flame on a candlestick that consist of 8 different pngs, and I need to loop that.

Help me follow.

You've got a sequence of PNGs in the timeline, with Smooth Cut transitions between each.

You then make that group of images a Compound Clip?

Where does Fusion come into it?

Thank you for taking time to look into my issue. I was probably unprecise with the way I phrased it.

I meant fusion only in the following way: it makes no difference if I create a new fusion clip or composite clip out pf the sequence of png-s the issue is the same. By creating a new fusion clip I mean selecting the clips with the transitions, simply right click, and select 'Create new fusion clip' (or something similar, don't have it front of me right now).

Got it.

And...why make them into a Fusion clip?

Just as a workaround as it failed with the compound clip. I would really like if I could make it work somehow with the compound clip.
I just wanted to emphasize that I tried combining them with the fusion clips as well, which yielded the same result.

Well, I don't want to use it, if I do not have to. I just wanted to emphasize that I got the same result when I tried to combine the png-s with compound clips and when trying to combine them into a fusion clip.

If there is a solution that would avoid fusion clips or fusion altogether, that would be the best.

(sorry if something similar gets posted, I may have already submitted a post like this)

I'm having the same issue with every transition. I also tried adding an alpha output in the color page, but that didn't solve the problem either.


I've found this thread which seems to relate:
https://forum.blackmagicdesign.com/viewtopic.php?f=21&t=126900

As of right now though, there don't seem to be any answers there either

Just as a workaround as it failed with the compound clip.

OK. But...why make it anything else? Just use the timeline as a clip.

Cause I need to repeat it tons of times for an hour or more.

The video (or at least the imagery) I'm currently creating will serve as visuals for 1-1,5 hour music mix on Youtube. It's similar to those well known "lo-fi for studying and relaxing" mixes, you've probably seen (if not, it's worth a look).

My visuals feature a background, where some stuff needs to be animated. I'll give 2 actual examples I'm using.

1. Simple animation for candle flames
- there are some candles in the background, and I have 9 "frames" of the flames on 9 seprate .png-s I wish to put on them
- After the 9 png-s are meshed together, the "animation" is put on repeat
- Each frame is shown for 6-8 frames (in 24 fps) and then they transform into each other using smooth transitions
- I need to create compound clips out of this so it becomes manageable otherwise I'll have 19.200 clips (given an 80 min long video, with 24 fps and each png lasting 6 frames) on one track only each with a transition between them which makes working with resolve impossible (at least on my machine)

2. Varying animations for a cat
- Imagine a cat in a window moving it's tail, the movement of the tail is drawn in ~20 different png-s, and gives a nice feel when combined into each other with video transitions
- out of these png-s I can create different animations for the cat's tail (eg.: moving excitedly, doing half of the movement then going back, doing the full 20 png movement, etc, etc)
- it would be most convenient to store each "type" of movement for the tail in a different compound clip, so I could fit the "mood" of the movement to the "mood" of the music that is currently playing

In my case, there would be around 5-6 objects that are "moving around" to give the viewer something to look at while listening to the music.

I'm not sure if links are allowed, but this is one of the most popular examples of what I am trying to recreate with my spin on it:

I hope I could explain it well.

Edited for grammar.

OK.

I'm thinking the work might be easier if you create a new clip of the animation segment. Something that holds an alpha, like DNx.

I'll give that a try - and maybe "converting" the individual png-s to a video format and combining them as video would also work... I hope.

I'll be in front of my editing machine tomorrow, and give an update on how it worked.

Well... it didn't work.

For me to export with alpha, I need to export as individual clips - which as far as I experienced it means I lose the transitions.

Exporting the png-s as separate videos with alpha, and trying to combine that with transitions and then combining those with a compound clips yields the same results when I tried to combine the original pngs (alpha gone while the transition lasts).

I'm on the verge of giving up and trying to pre-do the effects in some Adobe software - which I was hoping I didn't have to learn.

I'll keep experimenting a bit, maybe I'll stumble on some solution randomly... but at this point I don't have high hopes.

Version 17 has added the ability to export Alpha in Single file mode. Might be worth a look.

Standard backup caveats apply.

OH MY GOD IT WORKS !!!

I can't express how relieved I am. Thank you for all the help!

Anyone reading this in the future, in case you are experiencing the issue described above:
- Upgrade to Resolve 17 (preferably on a new machine while in beta)
- Join your clips with your transitions
- Go to deliver, select render Single Clip, in the format: Quicktime, Codec: DNxHR, Type: 444 12-bit (probably some other formats would work as well)
- Make sure "Export alpha" is ticked

You are all set!

Thanks a bunch again for the help!

Nice!

Hello,

I was having the same issue as this post.

With update 17 (17.1 Build 24) I can indeed export with alpha for single clip.

HOWEVER, my exported clip doesn't work fully. When the transition happens, the colours change as if the composite mode changes to add rather than normal, but only during the transitions. None of the original clips, nor the exported video imported into davinci again, have anything other than "normal" set for composite mode.

What's going on here?

Can you show us, Ken?

Sure. Here's a sample of what's happening.

This is what it should look like, with the transition part way through.
I've put in a coloured background on the lower half to show how the changing widget doesn't interact with the background at all.

This is what the end result actually looks like
(delivering without the coloured background of course, then putting the .mov onto the background in a new project). Once the transition is completed, the colours go back to normal. Best I figure is that it's treating the composite mode like add *only* during the transition, but the drop down for composite mode is on normal at all times (untouched throughout the project).

What's more on further inspection, this happens to all but the top-most video layer in my delivered .mov file. That top-most layer is rendering correctly.

I have managed to work around the issue by delivering individual layers as their own .mov files, and then using those as layers. However it doesn't explain why it's making these unexpected colour composite mode changes during transitions when I have multiple video layers.

Interesting workaround but it's cumbersome.

I'm wondering why this bug is not tackled as it should, and definitely solved

Interesting workaround but it's cumbersome.

I'm wondering why this bug is not tackled as it should, and definitely solved

Yeah this can be an annoying issue. BMD are definitely aware of it - a friend of mine was on the phone with them the other day regarding it.

From my own testing, it doesn't occur if you limit yourself to Fusion effects. Non-fusion transitions (like Cross Dissolve) will break alpha inside a nested container, but a Fusion Transition won't. Fusion compositions should likewise be OK.

If the problem is related to using transitions in compound clips, there's now - in DR 17, a smart workaround: use Fusion transition instead of the native resolve one:

viewtopic.php?f=21&t=94564

Hope it helps,
Mario

If the problem is related to using transitions in compound clips, there's now - in DR 17, a smart workaround: use Fusion transition instead of the native resolve one:

viewtopic.php?f=21&t=94564

Hope it helps,
Mario

Even without transition the Alpha is gone. I hope in the 18 the solved this issue

Hi all,

Interesting to read this thread.
I have a similar issue.

Some text clips with transitions on them, along with some tiff sequences, all bundled into a compound clip.
The alpha channel of the compound clip becomes fully opaque during any transition of the clips text clips within the compound clip.

I don't want to render any of the clips because 'flattening' defeats the purpose: I want to be able to come back and adjust transitions, position, scale etc of anything inside my compound clip without having to flatten again each time.

I'm using Resolve 17 still - does anyone know if this has been fixed in 18?

PS - Thanks Mario - fusion transitions have indeed fixed the issue for me. Hopefully the stock transitions will work too soon, or already do in 18. I love the convenience of right clicking to get a dissolve without having to worry it will break stuff further down the line.

Yes I have this issue as well.

I have a series of png's, actually an animation brought in from blender in single image mode with transitions on each clip. Each clip changes in time with the music track (bpm=120 so each clip is 2 seconds).
It is a composited sequence with a foreground, middleground and background, as well as some overlays and effects.

I want to add a letterbox effect to that part of the project.

(Another issue is that I can only add the letterbox effect to the whole of the output file using timeline>output blanking where as I still want to output 16:9 and have titles in the black area).

This means that my pngs are a little to low at the beginning and too high at the end. So I want to animate the whole thing drifting up. To do this I need to conform the foreground in order to have the picture move slowly over the 4 minutes or so.

But creating a compound clip, the alpha channel disappears so I no longer have a composited clip. I could try removing it using fusion but its fiddly and I shouldn't have to. I am using Resolve 17.4.6.

Is there really no setting to force Resolve to create a compound clip with alpha?

Yeah.. alpha is still sketchy with compound clips, i have a single off plus alpha that i need to make it a clip (for grain reasons) and as soon as I compound it, alpha is lost…

Yeah.. alpha is still sketchy with compound clips, i have a single off plus alpha that i need to make it a clip (for grain reasons) and as soon as I compound it, alpha is lost…

Hi Walter, can you describe this a bit? I'm trying to reproduce on my MacBook - What codec is your source clip with alpha? Thx

Add - I'm trying several of the examples mentioned in this thread with the 18.5 beta 2 version of Resolve - is it possible BMD fixed this issue in the latest? Or maybe I'm missing an important detail of how to create the problem. Thanks again.

Add2 - Is it possible that the loss of alpha is related to render caching? I don't have render cache active in my tests. I'll enable it and see what happens...

Yeah.. alpha is still sketchy with compound clips, i have a single off plus alpha that i need to make it a clip (for grain reasons) and as soon as I compound it, alpha is lost…

Hi Walter, can you describe this a bit? I'm trying to reproduce on my MacBook - What codec is your source clip with alpha? Thx

Add - I'm trying several of the examples mentioned in this thread with the 18.5 beta 2 version of Resolve - is it possible BMD fixed this issue in the latest? Or maybe I'm missing an important detail of how to create the problem. Thanks again.

Add2 - Is it possible that the loss of alpha is related to render caching? I don't have render cache active in my tests. I'll enable it and see what happens...

was a single tiff plus alpha, repeated for 3 second, make a compound clip and try to put grain on the result : alpha was gone.....

Not seeing this, Walter (18.5 b2, Ventural 13.3.1(a)). I tried both a Tiff sequence and a single Tiff. Both had alpha and 16-bit RGB.

1. Put Tiff on timeline
2. Make Tiff into compound clip
3. Place a color under compound to see the background (for contrast)
4. Go to color tab and add a Film Grain to the compound clip
5. Looks fine, still has alpha
6. Render the clip on the edit page (ProRes HQ)
7. Still looks fine after rendering (render cache, not render-in-place, btw)

I even tried just adding the film grain OFX directly to the compound clip on the timeline to see if that made any difference (rather than to a node on the color page). It did not make any difference.

What else can I try? Can you provide a dra (including the Tiff)?

Not seeing this, Walter (18.5 b2, Ventural 13.3.1(a)). I tried both a Tiff sequence and a single Tiff. Both had alpha and 16-bit RGB.

at work we are still on 18.1.4/5, not in beta.....