Image with alpha channel

vvvv beta question
1

hello,
how would i overlay a live video with a pre-prepared video/image that includes an alpha channel?

i tried the blend.fx shader, but it doesnt include an alpha blend option.

thanks for a hint!
mkl

2

just use two quads (one with a VideoTexture (EX9.Texture VMR9) and one with a FileTexture (EX9.Texture) and combine them with a Group (EX9) ). that should do the job…
also read: EX9 Rendering ;)

3

ai mkl,

easy:
you put the videotexture on a quad that goes to the first input of a Group (EX9). then on its second input you connect a quad that has a filetexture connected with a still image selected that has an alpha channel (ie. .png or .tga). that will be it. as the quad drawn last has an alpha channel no special blending is necessary.

for overlaying a video with a second video it is a bit more tricky, as videos cannot have alpha channels in vvvv…

4

ha, beat yo to teh point! joregs answer is more thorough though, but mine has a these silly wiki links… :D

5

A quick search yields the following threads (which all provide answers to your question):

so please search before posting.