A direct method to export mattes to external applications, such as Fusion??? Possible???

[Glenn Sakatch]

have you tried loading the rgba file into fusion and adding a channel switcher?

If there is alpha embedded in the resolve output it should work.

Glenn

[Dmitry Kitsov]

Hello, Mike. My post that you have referenced, was true prior to Resolve, with version 12.5 release, being able to embed alpha channel to some of the output format/codecs combination. It is still true and the grey scale matte image is still a valid method that can still be used be used.

Dmitry Kitsov,
Blackmagic Design technical support agent

[Michael Mccune]

Thanks, Dmitry; … did not quite understand: are you saying simply that:

1) version 12.5 was the first to include alpha channels in some Delivery tab format options??? [agreed] and,
2) that the black-and-white image export method (still) works; [agreed] and, finally, that
3) the Resolve alpha channel is indeed not recognized by other applications, e.g., Fusion)???

If so, we are on the same page in that regard!

Or, perhaps I misunderstand and you *ARE* saying that the Resolve alpha channel *IS* recognized by external apps, such as Fusion. True???

Please clarify.

Going forward:
FWIW, as you already know as a professional, Fusion matte tools such as LumaKeyer work wonderfully for the purpose of creating a matte from a natural image (i.e., not from a green or blue screen image source). I discover, among other things, that it includes its own LumaKey gamma and contrast sliders among other refinement controls.

Experts will know better than I, but it seems to offer more control than with a natural image source than the control possible when starting with a B/W Resolve output source, as much of the range and potential for Fusion key refinement is, at that point, already baked into the Resolve B/W output.

In fact, if I understand this correctly, the irony would seem to be that the greater the delineation and definition (usually desirable in a matte) that is baked into a Resolve B/W output actually and severely limit the potential for Fusion to apply its LumaKey adjustments, such as contrast and gamma adjustments.

Am I understanding this correctly?

Please clarify any misunderstandings you find here.

Thanks, Mike

[Dmitry Kitsov]

There are no issues with alpha channel as included by Resolve that we know of.

Dmitry Kitsov,
Blackmagic Design technical support agent

[Michael Mccune]

Thanks, Dmitry; Question: how properly to export alpha channels???

Which Deliver tab codec would you use to generate an alpha channel (RGB+alpha) for import into Fusion?

I am asking as I cannot seem to generate a 4-channel output, that is, RGBA, for Fusion.

Here are my steps: please correct any mistakes or note better ways to do this.

Base case:
1. I have a node (the last one in a very simple node tree) with a key mask feeding the output: the node tree output has both an RGB and an alpha output.
2. The key mask in the last node can be verified using the highlight mode which shows the individual node output (as opposed to the node tree output) and selecting the key tab;
3. On the Deliver page, I select a codec that should, I believe, generate a 4-channel output, such as QT Uncompressed RGBA.
4. The exported file is inspected for bit depth and the number of channels. But it shows only three channels in the output video. The output video is of the mask; in other words, it is a video version of the key mask: black surrounding the key mask area.
5. Checking the file metadata using MediaInfo, file manager properties or importing into Photoshop, all show only three channels.
5. Imported into Fusion, the video version of the key mask appears as expected; that is, a black area surrounding the key mask area. But there is no 4th or alpha channel. Selecting the Fusion button for color/alpha under the display window displays only a field of white (opaque).

Please clarify this and detail your approach to generating a 4-channel output from Resolve to be imported into Fusion.

Thanks again, Dmitry. I very much appreciate the help of your professional experience in this.
Mike

[Glenn Sakatch]

So i gave this a try, thinking…it can’t be that hard right?

First off, i exported a series of shots, same idea … put a power window on it, add an alpha output node and export.
Right away i’m wondering “just because the power window is there, does that create an alpha output, or do we need to do some other song and dance?”

I exported a dnxhq, dnx444, dpxrbg, tiff16bits, uncompressed argb, uncompressed bgra, and an uncompressed quicktime.

Brought each of those into fusion, turn my viewer to alpha, and each showed full screen white, no power window key.

I then brought each back into Resolve, and under clip settings, set each to have an alpha channel. The dnxhq, tiff16bits and uncompressed each came in as a keyable element, the others did not.

I then brought each into after effects. Of all those files, only the uncompressed bgra file gave me the option of assigning an alpha component, but it, nor any of the others, showed up as a keyable element.

So although it appears some files will export an alpha channel, they are only visable when brought back into Resolve. I’m sure there is a reason you might want to do this workflow….just not quite sure what it is, perhaps archiving elements for future use, but certainly not what most of us would think of as an alpha output workflow.

Glenn

[Michael Mccune]

Glenn; thanks for the thorough double-checking of this process.

And yes, one of the purposes of this round-trip within Resolve is to create an “archive” or version that is (re)usable outside of that timeline.

But, most importantly, your tests seem to reach the same general conclusion that 3 Resolve Delivery codecs work as keyable alphas when taken back into Resolve and that no Resolve codecs work in Fusion and only one in After Effects as an alpha component and none as an AE keyable alpha.

Dmitry, BMD Support said in this thread, [Dmitry Kitsov] “There are no issues with alpha channel as included by Resolve that we know of.”

But I wonder, as you do: [Glenn Sakatch] ” or do we need to do some other song and dance?” For example, to get them to work in Fusion, a close relative to Resolve.

At least the proper method is not obvious. Unless Dmitry meant to say that a B/W rgb image of the Resolve key is the only “alpha” that Resolve has and that it is, indeed, in lieu of a keyable alpha.

Thanks again, Glenn; Onward and upward!
Mike

[Dmitry Kitsov]

Following codecs were exported from Resolve 12.5.4 and opened in Fusion with alpha intact on Mac OS X:
DNxHR444.mov,
GrassValleyHQX.mov,
GrassValleyHQ.mov,
ProRes4444.mov,
ProRes4444XQ.mov,
UncompressedARGB.mov,
UncompressedBGRA.mov;

After Effects 2017 accepted with Alpha intact:
ProRes4444.mov,
ProRes4444XQ.mov,
UncompressedARGB.mov,
GrassValleyHQX.mov,
GrassValleyHQ.mov,
UncompressedBGRA.mov.

Please make sure you have appropriate codecs installed, where appropriate for the third party application support.
Please refer to the references like operation manuals for mentioned applications on the information on how to produce or import media with alpha.

Dmitry Kitsov,
Blackmagic Design technical support agent

[Michael Mccune]

Thanks for this list, Dmitry;

To get started, this list is also valid for Windows, correct??? I note that you begin your list by saying that these alpha codecs were valid for MAC OS.

Mike

[Dmitry Kitsov]

Not all of the codecs are available on Windows (for example you will not be able to deliver ProRes on Windows). There is also a possibility of different feature set on Windows platform, than that available on macOS, for the same codec.
A thorough testing of any intended workflow is recommended.

Dmitry Kitsov,
Blackmagic Design technical support agent