major Magic Mask problem! (Studio, obviously)

So I spent a long time masking up a video - it is my niece against a busy background and a LOT of fiddling was needed. I probably ended up doing strokes on every 3rd frame or so had about 900+ strokes in the end and got a pretty good result but it was a LOT of work.

(The idea being to then take her and paste her into another piece of footage / background)

I saved the project, closed down and restarted next day - the clip is still there but all the mask data is gone, and the clip that remains is super glitchy. And I mean REALLY glitchy. And the alpha channel has disappeared too.

I assumed that I had forgotten to save it, so spent another metric crap-ton of time rebuilding it from scratch. It's a time consuming project not a 'one session' proposition so again I saved it (ensuring I also had auto save while doing it etc) and now I reopen today and it's the SAME issue, and I am very unhappy.

(It also seems that the audio has moved to a different place in the time line whereas it was under the video, but that might be wrong. Just thought I'd mention it, in case.)

Does anyone have a 'fix' for me please? This is driving me mad - in both meanings of the term.

[Peter Chamberlain]

Once you have made the magic mask render it in place.
That will get you around your current project deadline so further investigation can occur as to why its loosing the data on restart.

Hi Peter,

Do you need anything from me for an investigation?

I'm not keen to redo the mask until I can be satisfied the issue is resolved, at risk of losing it again. It's not time critical for me.

I do note that from some googling I am not the only person having such issues - many have - and it doesn't appear to have commenced with the 18.6 update but may have been an issue since the introduction of the magic mask tool, or at least as far back as 18.2 I hope this helps.

Are you really losing the mask or are you just losing the cache? Most likely it's the latter, and if so, you just need to regenerate the cache from the MagicMask options menu.

It's happened again. I tried with a different clip, from scratch and it was working - until it wasn't.

Seems to be gone completely mate - says no magic mask, the alpha output has also disappeared BUT visually it has been separated from background but background is black rather than alpha.

I tried adding an alpha output again and connecting but that made no difference.

I tried the regenerate the cache option (both selected clip and all clips but absolutely nothing happened)

I've attached screen shots in case helpful.

screenshot as was

001.png (290.04 KiB) Viewed 568 times

added alpha no effect

002.png (327.57 KiB) Viewed 568 times

This is driving me crazy!!

Hard to say whats going on there Michael, very weird if that happened without prompting.
Looks like what I'd expect to see after the magic masked clip instance has been made into a compound clip, or a rendered in place clip.
Very odd (unless thats what happened obvs)
Hopefully someone else has an idea.

I think I may have tried to render it in place as a fix (i.e. once this happened) but that's not the cause.
If I did render in place can I go back to get rid of that to at least eliminate one possible issue?

As for a compound clip - I'll check when next at my computer - but if that happened somehow, surely that wouldn't delete the alpha channel would it?

EDIT: Somehow it was a compound clip. I decomposed it and alpha is back.

I decomposed it and alpha is back.

Cool.

Michael, cool down and first try what was proposed to you... Trust me, I've answered this a lot recently, because I personnally checked any solution months ago now. If you search the forum about that, you'll find tons of threads about this very topic, which is known and discussed a lot.

So YES, if you Render in Place in the edit page what you just finished in the Fusion tab, you can close the project and/or Resolve, you'll be able to find your alpha and your track at reopening the project
And YES, you'll also be able to Decompose in Timeline to find back your nodes...
Peter also had suggested this to you 3 days ago now

Sam - I appreciate you are trying to help but note that I had posted I'd managed to get it fixed, prior to your post. I don't need to 'cool down' - I wasn't even aware I was hot! God to know though

If you search the forum about that, you'll find tons of threads about this very topic

Which shows that there needs to be more thought put into this problem (or issue) by BM so that users can avoid it in the first place. Hopefully it will be 'fixed' in the next patch/update.



Cheers all, I appreciate your help greatly.

Hehehehe, no problem... I noticed you didn't try the most efficient fix imho 3 days after it had been suggested to you, that's all
Above all I wanted to add you can reverse the Rendr in Place, which makes it a pretty good solution while waiting for an update

So I spent a long time masking up a video - it is my niece against a busy background and a LOT of fiddling was needed. I probably ended up doing strokes on every 3rd frame or so had about 900+ strokes in the end and got a pretty good result but it was a LOT of work.

My opinion: there's a lot of things that CAN be done in Resolve, but it shouldn't necessarily BE DONE that way. I think this is an example. It's kind of like trying to use a big wrench as a hammer: you can do it that way, but sometimes it's better to just grab an actual hammer.

I think you're basically trying to cut out a foreground person/actor from a shot and exclude them from the background, which is essentially the point of chroma key (aka green screen backgrounds). To me, that's not what Magic Mask is for.

There are tools like Mocha Pro and other sophisticated 3rd party VFX software that you can use for this purpose, but there's a learning curve and it does take time.

For me, Magic Mask is just a "quick and dirty" way of cutting most of a person out of the background and maybe splitting the color correction between the person and the background, or maybe throwing the background a little bit out of focus, or darkening it, or otherwise placing more emphasis on the person. I think trying to use it as an actual compositing tool is going to be a long and lonely road.

Read up on VFX compositing and see what pro VFX artists are using for compositing. Fusion could potentially be a better tool, and if you're drawing 900 strokes to get movement/shape samples, I think you'd be better actually cutting out the person on a frame-by-frame basis. Steve Wright's Digital Compositing for Film and Video: Production Workflows and Techniques is one of the standard texts on the subject:

https://www.amazon.com/Digital-Composit ... 138240370/

Ron Brinkmann's The Art and Science of Digital Compositing: Techniques for Visual Effects, Animation and Motion Graphics is also good, but somewhat dated:

https://www.amazon.com/Art-Science-Digi ... 0123706386

You can get more info on Mocha here:

https://borisfx.com/products/mocha-pro