Unwanted transparency in track matte for Stinger Transitions

[WeAreMemnor]

Hey folks, my first time making stinger transitions, so apologies if I'm being dense, but couldn't find good wording to google the problem.

On putting my stinger on (I'm using stinger on the left, track matte on the right), it seems to make the scene slightly transparent, as if the black in the track matte is not properly black. I've gone through the video file I've uploaded and ensured that the black in the track matte is definitely #000000, so I can't think of why it's displaying the scene as transparent.

The screenshot is showing pre-transition, where you can see that the A slide is showing slightly through the B slide. Hope this is helpful info, and that someone can shed some light, because I'm kinda stuck.

The video file was exported as Quicktime GoPro Cineform RBG with alpha, for the transparency on the Left hand side of the video. Doesn't seem to have the problem when exported as an .mp4, but then I lose transparency.

Log File in case it's any help in this situation.

Cheers, all.

 

[WeAreMemnor]

OK!

So apparently it took me a month to crack but I've seen some people on youtube ask a similar question so I shall post it here for posterity.

If you're using resolve, you can't export straight to .webm, so you have to export to .mov or something similar for transparency on the left side of the stinger (the graphic). This is fine, but it turns the black on the right side (the track matte) into a very dark grey, hence the slight transparency.

The way that I got around this was exporting the 2 videos seperately:
The stinger graphic i exported as a .mov to preserve transparency and converted into a webm afterwards using ffmpeg

ffmpeg -i in.mov -c:v libvpx-vp9 -pix_fmt yuva420p out.webm

And the Track matte I exported as an .mp4, and then applied (almost) the same process to turn it into a .webm

ffmpeg -i in.mp4 -c:v libvpx-vp9 -pix_fmt yuva420p out.webm

Then I used a separate ffmpeg command to put the 2 together for the final stinger transition

ffmpeg -c:v libvpx-vp9 -i left.webm -i right.webm -filter_complex hstack output.webm

the final transition works in OBS with all the transparency where it should be and the blacks remain true black.

 

[craftykaname]

OK!

So apparently it took me a month to crack but I've seen some people on youtube ask a similar question so I shall post it here for posterity.

If you're using resolve, you can't export straight to .webm, so you have to export to .mov or something similar for transparency on the left side of the stinger (the graphic). This is fine, but it turns the black on the right side (the track matte) into a very dark grey, hence the slight transparency.

The way that I got around this was exporting the 2 videos seperately:
The stinger graphic i exported as a .mov to preserve transparency and converted into a webm afterwards using ffmpeg



And the Track matte I exported as an .mp4, and then applied (almost) the same process to turn it into a .webm



Then I used a separate ffmpeg command to put the 2 together for the final stinger transition



the final transition works in OBS with all the transparency where it should be and the blacks remain true black.

I literally made an account on this forum JUST to thank you for updating the post with your solution! Worked perfectly.
I NEVER would have figured out that exporting it the way necessary for alpha would affect the color of the black. Had the exact same issue on mine!

If you had just said "use FFMPEG" I never would have succeeded, but even a dummy like me could do it since you shared your exact commands! Thank you, thank you, thank you!!

 

[craftykaname]

Hello! I actually have another update.

Before coming to this forum, I asked on the Blackmagic Design Discord.

User "FoldableHuman" figured out what settings to use to fix the ghosting issue!

Switching Data Levels from "Auto" to "Full" is what should fix it! No need to export separately anymore.

 

[bergocean]

Hello! I actually have another update.

Before coming to this forum, I asked on the Blackmagic Design Discord.

User "FoldableHuman" figured out what settings to use to fix the ghosting issue!

View attachment 86604

Switching Data Levels from "Auto" to "Full" is what should fix it! No need to export separately anymore.

I was looking for this type of solution everywhere. As you said 'I literally made an account on this forum JUST to thank you for updating the post with your solution!' Thank you so much!