Hi,
I couldn't find anything specific to this topic on the forum or in the manual for v2.3.1.
In a greenscreen Webcam feed into MMV (chromakeyfast used on the input), some transformation I use seem to create a "black background". For instance, "optical flow generator" seems to no longer allow any transparency resulting in a completely black opaque background. Is there a work around this?
Thanks!
ChromaMask / Chroma Desaturation
Re: ChromaMask / Chroma Desaturation
Some of the effects don't support alpha channels. I'm not really sure if there's a "workaround" per se.
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Re: ChromaMask / Chroma Desaturation
Not a general workaround, but there are possibilities that will work in certain cases. The first two below will give different results - hopefully one or the other will be useful to you.Eric wrote:Some of the effects don't support alpha channels. I'm not really sure if there's a "workaround" per se.
1) In the case of the "Optical Flow Generator" you could restore transparency to the black regions by following it with the "Luma Key" module. Try Strength = 0.01 and Falloff = 1.0 as a starting point.
2) You can use the Vidvox "Show Alpha" ISF module to extract the alpha generated by "ChromaKeyFast". The alpha can then be re-applied after the effects chain by using using Magic's "Mask" module with "Use Alpha" unticked. I've attached the "Show Alpha" module. I found it here: https://editor.isf.video/shaders/5e7a7f ... 18206de179 .
3) On the offchance that you find a distortion module that sets alpha to 1.0 rather than distorting it to match the image you could try the "ChromaKeyFast" after the distortion rather than before.
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Re: ChromaMask / Chroma Desaturation
Here's a demo, using the Match Alpha method (#2) and the "Edges" module in place of the "Optical Flow Generator".
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Re: ChromaMask / Chroma Desaturation
Adding an "Erode" module in the alpha feed to the "Mask" module will add a black border (right-hand image). This can be useful to isolate the camera image from the background if it would otherwise be hard to distinguish.
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Re: ChromaMask / Chroma Desaturation
Thank you so much for the posts i'm going to look into it tonight. I want to say, i'm so glad i got this software, the support on forums is amazing. I'm doing publicity for you guys on twitch, people are losing their minds!
Perhaps it should be a whole other post, but would you know if there is a way to control the scene switch via OBS rather than via the playlist? I can post this standalone as well, let me know what is the best course of action.
Cheers and thanks again!
Frank
Perhaps it should be a whole other post, but would you know if there is a way to control the scene switch via OBS rather than via the playlist? I can post this standalone as well, let me know what is the best course of action.
Cheers and thanks again!
Frank