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Fading the edges of a video to be transparent

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igloo
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Hi all,

I can use the Affine transition to get a picture-in-picture effect, but that gives me very sharp edges to the small video. I would like to have it fade out at the edges instead.

I can use the Region transition to do this, by using one of the square wipe files. However, Region is one of the transitions that gives a green tint to the video.

Is there a way to do this without the green tint please?


Thanks
Ian
TheDiveO
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What you probably need is not a transition but instead an effect that manipulates the alpha channel of your clip in the timeline. If you look at the effects list you should see a category for alpha manipulation (sorry, don't have the precise category ready as I'm using a localized Kdenlive where the categories are named diffrently).

The is an effect especially for creating alpha masks from a few geometric base figures, such as rectangle, ellipse, triangle. You can control the extend and placement of the shape as well as how smooth and wide its border should be. Just add this effect to your clip. Often, the alpha mode of write on clear will be sufficient ... unless you are working with clips that already have some alpha channel data that you need to deal with.

In your case, you don't have any video alpha data, so the effects writes on clear, that is, the effect now sets the alpha channel of your clip. However, you may need to compose ypur clip to either another track or black in order to get proper video out without the green tint.

For instance, I'm regularly using a PNG bitmap image with transparency as an end credit. I have to compose it with a black clip in order to get rid of the green tint in regions of partial transparency.
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ttguy
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If you use a recent build git build of mlt you might fix the green tint bug - http://sourceforge.net/p/mlt/bugs/198/ - 198 wipe transition causes green tint "Fixed in git commit 2aaa902. I will close this ticket on the next release."


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