Methods and apparatus to detect an internally generated signal mode of a local media playback device are disclosed. A disclosed method comprises tuning a harmonic frequency of a chrominance signal output by a local media playback device, and determining that the local media playback device is in an internally...http://www.google.de/patents/US20090265730?utm_source=gb-gplus-sharePatent US20090265730 - METHODS AND APPARATUS TO DETECT AN INTERNALLY GENERATED SIGNAL MODE OF A LOCAL MEDIA PLAYBACK DEVICE
