[Cin] How do I crop a picture-in-picture?

Phyllis Smith phylsmith2017 at gmail.com
Fri Apr 17 01:18:15 CEST 2020


Have you tried the "Crop & Position" plugin instead of the "Crop tool" in
the Compositor?  IgorBeg is the expert on usage.

On Thu, Apr 16, 2020 at 4:43 PM David Given <dg at cowlark.com> wrote:

> I have two video tracks; one is overlayed on the other. I'm using
> projector automation to put the overlay video in the corner of the
> underlying video. I would like to crop the overlay video so it only shows
> the section I'm interested in. The overlayed video is a 1:1 image in the
> middle of a 16:9 video, and I just want to show the 1:1 bit. I can't figure
> out how to do this.
>
> - I thought I would be able to use the camera automation to scale the
> image after I had placed the projector, but while this works, it happens
> *before* any track plugins are rendered, and as one of these is rotation
> I always end up with a rotated rectangle on the screen. (With black
> borders.)
> - using the crop plugin adds more black borders.
> - I tried a mask, but I haven't found out how to invert the mask (i.e. I
> draw the area I want displayed so that everything else is cropped); plus
> cropped areas show up as black.
> - I simply can't get my head around the crop tool.
>
> The best I've come up with is to add a scale plugin to the track to resize
> it up a bit, so that the black wedges caused by the rotate plugin aren't
> visible; then adjusting the camera to zoom in on the are I'm interested in;
> but I haven't found a way to change the *shape* of the projector yet.
> It's always a 16:9 rectangle, but the area I want to show isn't that shape.
>
> What's the right way to do this? Ideally what I would like is the ability
> to draw a path on an object on the screen and say 'clip this object to this
> path'. Does anything like that exist?
>
> --
> ┌─── http://www.cowlark.com ───
> │ "I have always wished for my computer to be as easy to use as my
> │ telephone; my wish has come true because I can no longer figure out
> │ how to use my telephone." --- Bjarne Stroustrup
> --
> Cin mailing list
> Cin at lists.cinelerra-gg.org
> https://lists.cinelerra-gg.org/mailman/listinfo/cin
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.cinelerra-gg.org/pipermail/cin/attachments/20200416/79e1db53/attachment.html>


More information about the Cin mailing list