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lumakey
Posted: Fri Sep 17, 2004 6:33 pm
by mo
i tried this yesterday and found that i cannot get it to work as i would like to - or at least how i am used to it from resolume. there does not appear to be a control that selects at what threshold something will become (completly) transparent. does this mean the transparency is simply proportional to the luma as opposed to either fully transparent or not depending on where the luma is relative to a selected threshold?
i guess both methods have their merrit. i am just trying to understand how to get 100% transparency.
mo
Re: lumakey
Posted: Fri Sep 17, 2004 7:03 pm
by yves@garagecube
mo wrote:i guess both methods have their merrit. i am just trying to understand how to get 100% transparency.
You have several ways to generate transparency: global alpha-blending (in the layer list), predefined per-pixel per-frame transparency (stored in your media) or using luma keys. To get 100% transparency, simply use the alpha-blending slider in the layer list.
Yves.
Posted: Fri Sep 17, 2004 7:36 pm
by mo
i meant 100% transparency of certain areas in a clip. i.e. if i want everything that is 128+ (assuming 8-bit grey scale for now) to be 100% transparent and everything else (0-127) to be non-transparent would there be a way to achieve that using the luma keyer?
mo
Posted: Fri Sep 17, 2004 9:56 pm
by yves@garagecube
mo wrote:i meant 100% transparency of certain areas in a clip. i.e. if i want everything that is 128+ (assuming 8-bit grey scale for now) to be 100% transparent and everything else (0-127) to be non-transparent would there be a way to achieve that using the luma keyer?
mo
Currently the lumakey maps directly the color channel to the transparency channel (alpha). So for the standard luma key, black is 100% transparent and white is 100% opaque.
Yves.
Posted: Fri Sep 17, 2004 11:16 pm
by boris
One trick for the moment, you can use (and adjust) the Contrast fx in the same time of the luma key.
The contrast is applied before the luma key and you will be able to have better results.
The same trick works for the color key and the saturation fx.
We already discussed about this here :
http://www.garagecube.com/forum/viewtop ... luma%20key
Boris.