load a path from a raster based matte

[Ron Coy]

oh, man… I don’t know of a quick solution. Not with paths anyway. You could just use something that affects alpha edges.

I don’t know of any way to make paths from the alpha of the layer, except for a tedious importing of every frame into Photoshop and converting the alpha to a path, which doesn’t even work that well, or using the path tracing stuff in Illustrator, which also wouldn’t work that well, and would be even more tedious, or just Rotoscoping the whole thing, which, again, is tedious, but probably your best bet, with the best results.

you might try looking for an effect to affect the alpha, like Shine

[Paul Rijkaard]

There must be a way to deal with this – there just must be – all of the information other than the calculated vector line is available

just to confirm again – I would like to use the silhouette of a moving figure to trace the figure’s outline and use this outline as a motion path for a light beam effect.

Perhaps I am complicating it somewhere along the line?

I recently bought Shine and Form – but have spent most of my time in Form – can you briefly explain what it can do for alphas??

[Ron Coy]

Shine doesn’t do anything for alphas, but if you have element in your scene with an alpha channel, obviously, Shine can effect just the edges of the element as opposed to the entire thing, or just the alpha channel itself. It’s a drop down menu within the plugin settings box, I believe it’s Composite and the options are “On Original, Alpha, and Alpha Edges”. There may be another option, but I don’t have it open and in front of me right now.

With Alpha Edges selected, you can adjust the settings to give an edge glow type effect that’s more dynamic than just a standard glow. As far as extracting the path from an alpha, I just don’t think there is a tool for that. Maybe someone should or will make one, but I don’t know of one.

Try going to Toolfarm and looking for something there. They are basically plugin central.

[Ron Coy]

ok. I found something that might work, but it’s in beta.

Masks to Shapes

http://www.redefinery.com/ae/view.php?item=rd_MasksToShapes

There is also one called Shapes to Masks

http://www.redefinery.com/ae/view.php?item=rd_ShapesToMasks

One of these may be able to get you there. They only work in CS3 though.

[Paul Rijkaard]

Thanks for this – although there is still the problem of generating a shape/path from a raster file – although it could be conceivable to write an action in photoshop that loads each frame selection and makes a path –

but this leads to a problem of how to bring together many paths into one keyframed/roto path??

perhaps the answer lies back in motor/mocha which can export shape data but not to after effects – only to combustion/flame/shake

does anybody know of a work around with this? I am not familiar with these applications??

[Jeff Kosmicki]

Sorry for the late response, this may be too late but you can select the layer you want to make a mask for and then go to layer/auto-trace. You can then select to make a static mask from a single frame or animated from a range of frames.

Jeff Kosmicki
http://www.toyraygun.net

[Jeff Kosmicki]

Sorry for the late response, this may be too late but you can select the layer you want to make a mask for and then go to layer/auto-trace. You can then select to make a static mask from a single frame or animated from a range of frames.

Jeff Kosmicki
http://www.toyraygun.net

[Paul Rijkaard]

Thank you so much – it is such an obvious command that has been staring me in the face but it really really has solved my problems. the results are incredible. thank you thank you

paul richards