Video frame capture conversion to photo (jpeg?) software

[nyslowhand]

Anyone use any freeware programs sucessfully, that capture a single video frame and convert it to a photo w/o degrading the quality?

 

Saw one that looked interesting on Cnet, but thought I'd get some input first.

[First-light]

I work on a Mac and use a number of programs.

http://www.macworld.com/article/1154212/pullingstills.html

[nyslowhand]

Should have been more specific; Windows Vista and trying to capture frames from DivX video and convert to most any photo format like jpeg.

[WNYBuckHunter]

All i do is pause the video and use the snipping tool in windows to capture it.