Software for removing backgrounds on video

[Ashkan]

hi dears
i want a software that can erase any part of video in frame by frame mode.
i explain it:
i am in frame one of a video and select an erase tool and start erasing part of frame like same work on photoshop and on image file but i want do this on video file.
if i erase some part of frame one i don't want to erased that part on other frame, every frame is keyframe.
please tell me this software for do same work.
thanks alot

[mats.hogberg]

Well, only way I can see, is to export each frame as an image, edit the images, and lastly bring back the images to a video again. If you have an AVI, VirtualDub can do it both ways AFAIK. (Both save as image sequence and make video from image sequence.)

/Mats

[thecoalman]

The video has to be shot with this in mind, usually with a solid blue or green background. Google chroma key or composting. It doesn't necesaarily have to be blue or green just a solid uniform color. Trying to remove a background from a video that is not uniform is all but impossible without doing each frame individually as mats suggested. The only exception would be if it's the area you want to remove is static, or only varies slightly over set amount of frames. In that case you could apply a mask and even keyframe the size and location of the mask.

[guns1inger]

The best option would something like After Effects or Fusion, where you can keyframe bezier masks to isolate objects and exclude everything else. It is a technique called rotoscoping, and it is time consuming work. Usually you cover most of the frame with one or more garbage mattes, then use bezier splines to refine the edges of your target shape - person, car etc. You can then drop the results over a new background.

http://www.eyeonline.com/Web/EyeonWeb/Techniques/tips_tricks/newtips/tip_105.aspx shows you one way to do it in Fusion

An alternate approach using vector paint in AE -> http://forums.creativecow.net/cgi-bin/page_wrapper.cgi?forumid=2&page=http://www.creat...tte/index.html

Although this is for a green screen key, it is a good explanation of junk or garbage mattes -> http://forums.creativecow.net/articles/rabinowitz_aharon/junk_mattes/CC_Junk_Mattes.mov