Rotoscoping black screen help?

Hi everyone, i have been rotoscoping in Hitfilm express (a little new to it) and i have spent a long time rotoscoping a few things for a project which worked pretty good. but the only thing is i tried to use the things i rotoscoped out in a other video but the object is there that i cut out but has a black screen behind it so i right clicked on it and went to blend then clicked on screen and the object is Transparent?? i have tried all the blend options and nothing is working i really don't want to rotoscope again?? 

Comments

  • Triem23Triem23 Moderator Moderator, Website User, Ambassador, Imerge Beta Tester, HitFilm Beta Tester Posts: 18,305 Ambassador

    So... You rotoscoped your footage and rendered it out as an mp4 for reuse? 

    To reuse roto footage you have two and a half basic options. 

    First, you can render to a format that supports alpha transparency. In Hitfilm Express on Windows that's "PNG Sequence with Alpha" or "GoPro Cineform RGB with Alpha," both of which are presets in the Export Queue.

    The other "option and a half" is to render out on top of a solid background - like a green - to key the re-imported footage. Since your footage has a black background you can try using either the "Demult" effect or "Luminance Key" effect to remove the black. How well this works depends on how dark the shadow areas of your roto are.

  • adamsfilms12adamsfilms12 Website User Posts: 67

    Triem23 Thanks for the reply i didn't even really know about the Demult effect thanks for teaching me something new. i have ended up rendering alpha transparency the Demult effect worked well but it had a few shadows that got in the way haha. thanks for the help and have a nice day!

  • Triem23Triem23 Moderator Moderator, Website User, Ambassador, Imerge Beta Tester, HitFilm Beta Tester Posts: 18,305 Ambassador

    Yeah, rendering with alpha to begin with is the better option, but Demult and Lumakey might have saved some time - as said above  it would depend on shadows. Glad to help!

    Keep Demult in mind. If you ever use fire/explosion stock footage that's the first step in removing the background. 

This discussion has been closed.