Amateur video of protests, violence and other news worldwide has become a staple of the Web. This exposure can be great for promoting a cause or revealing injustice. But it can also create problems for people appearing in these videos.

Law enforcement agencies, for example, have prosecuted people appearing in protest videos simply by analyzing faces and other clues in a piece of online footage.

YouTube, where most of these videos end up, isn't entirely comfortable with this loss of anonymity, especially when it's used to crack down on free speech. So the site recently introduced a tool that lets you automatically blur faces in footage you upload to the Web.

The site acknowledges that the new "Blur All Faces" feature isn't perfect. Sometimes it has difficulty picking out faces depending on camera angle, lighting, obstructions and video quality.

But preserving someone's anonymity online may help protect their privacy. That's a good thing, whether it’s a video of a Wall Street protest or just footage of your kids playing in the backyard.

—Larry Greenemeier

[The above text is a transcript of this podcast.]