Using SVG and the CSS mask property to 'knock out' portions of a video clip. In this example, we're using SVG <text> as the mask.
At the time of this writing, the example does not work in any version of Internet Explorer.
Tested and works on the following PC platforms:
Firefox (v27.0.1) and Chrome (v33.0.1750.154) on Windows;
Safari (v6.1.2), FF (v28.0) and Chrome (v33.0.1750.152) on Mac;
Firefox (v26.0.1) and Chrome (v31.0.1750.63) on Ubuntu.