[bug] fix the "Motion Blur" unusable trans. with png

The motion blur setting is totally unusable with transparent png.

Here you have transparency around the "shadow" and between the green and the blue (for reference).

It's crazy that this was never fixed since V17.0 :/

A simple "slid" left and it's a mess if the motion blur is activated (Resolve transitions on the edit page)

I'm finishing an edit now after 4h, I wanted to have more dynamique transitions...

Sometimes I don't get it, it's like nobody uses these transitions or transparent images with Resolve.
The most basic things are broken, why are they not fixed in the 0.x updates...

PS.
No, that's not the thing I was working on lol, but I made a quick example to post here.
And I think I reported this bug months ago (I can't find in my posts).

Oh and for testing purpose, the quick and ugly test png sample here : https://i.ibb.co/TbxTGYz/TEST.png

That sucks! I guess you could use Fusion but one would think that BMD might consider fixing this issue since the built in transitions can be useful.

That sucks! I guess you could use Fusion but one would think that BMD might consider fixing this issue since the built in transitions can be useful.

I used Fusion at the end to finish my project.

But yeah it sucks when basic transitions, from Davinci Resolve itself, don't work. So much waste of time for so little :/

There are so many problems with anything with a transparency. Png, animations, compound clips, etc.

I see all these 0.x updates, with the most obscure "bug fixe" (I'm sure they help some people, of course), but those that are the most visible are not taking care of. It's like nobody use the edit page and the effects pannel or something lol

There are so many problems with anything with a transparency. Png, animations, compound clips, etc.

Agreed. I just took your example and played around with compound clips and render-in-place to see if I could work around the issue (I was thinking that render-in-place with DNxHR 444 12-bit would give me transparency (which it did) and then I could apply a motion blur effect to that, however, the motion blur effect didn't appear to do anything - maybe I'm using it incorrectly).

Anyway, the only workaround I could find was using Fusion. The limitations imposed by using transparency in the edit page drives me a bit mad. Maybe someday but perhaps there is a low-level issue in the architecture that is making a 'quick fix' impossible.

Add - I just realized that render-in-place did not include the slide transition - so that's why motion blur didn't work. Oh well.

Yeah frustrating to battle with simple things like transitions :/
I love Fusion, but it's like using a bazooka to kill a fly, I just wanted to have a quick easy in/out transition with motion blur.

Edit : Thanks for your test

For anyone who is still reading this in 2025:

Go to Project Settings -> Image Scaling -> set it to Bilinear.

That fixed it for me.

You can also change Resize Filter settings at the clip level in the Inspector - Retime and Scaling - Resize Filter (Cubic and Bicubic usually best for me). And don't forget to disable Force sizing to highest quality in render settings.