Playing a video through a photograph

[number2goose]

Hi all,

I am very new to Isadora and, although I have a fairly basic understanding, I haven't been able to figure out this specific problem. I am attempting to create a stage image in which the image of an American flag is projected and a video plays through only the white pieces of the flag. My initial idea was to use photoshop to remove all of the white, however Isadora doesn't seem able to read the removed sections as transparent. Is the only way to manually add red shapes to the colored sections or is there a way to get it to play only through the white sections that is less time intensive. 

Thank you for any help.  

[DusX]

There are multiple ways to accomplish this.

But since it sounds like your flag image is a photo, it may be nicest to do as you suggested and remove the white with photoshop, saving the image as a PNG file with alpha channel.

You can then play this file with picture player connected to a projector with blend set to transparent.

Now play a video to another projector, and ensure its layer setting is at a lower number than the picture.

You should see the video thru the transparent sections of the flag. You may still need to work out placement and masking, so that the video doesn't appear outside the outer edges of the flag.

[jhoepffner]

Or make an alpha mask (select the white, invert the selection, save the selection…), leaving the white, saving as .psd and isadora recognize the alpha mask.

Jacques