Just wondering if anyone has encountered this problem before:
I am trying to key a character over a webpage, but I am getting this small white 1-2 pixel halo around him. When you look at it behind a background its fine in after effects. I have tried bringing it into flash but after I compress it with squeeze or in flash and put it behind a background (in flash) I see the white ring. I think this is a premultiplication issue. I have tried interpreting the keyed footage in after effects as straight and premultiplied and tried them both. It's pretty weird and I am wondering if anyone has gone through that problem as well, any input would be appreciated thanks!
I had a similar problem a while back. I'm pulling this from memory so I hope it will help. This was my work flow:
In AE I added a mask to choke/feather the the edges of the key a little. The footage I shot was HD, so rendered the key full size, no fields, uncompressed. After that, I took the rendered key and shrunk it down the correct size, still high quality uncompressed. Then I took it to the Flash video encoder and compressed it with an alpha channel. In the fla I added a slight inner glow filter to the video, similar to the background. In my case it was white. The background was a gradient that went from a orange-brown to white. So I imagine if your background was blue, adding a inner glow of the same blue would help cover in up the white outline.
We were going for a lower bandwidth, so the video compression settings reflected that, 15 fps and somewhere around 250 to 300 kbps. Probably lesser of an outline if compressed at higher quality.