Methods and apparatus to monitor audio/visual content from various sources

A multi-engine meter to monitor media content provided by a selected one of a plurality of media content sources for presentation by an information presenting device, the multi-engine meter comprising:

• at least one audio engine to process audio samples corresponding to the monitored media content;
• at least one video engine to process video samples corresponding to the monitored media content;
• at least one metadata engine to process at least one of the audio samples or the video samples;
• and
• a decision processor to evaluate information generated by the at least one audio engine, the at least one video engine and the at least one metadata engine, to identify the selected one of the plurality of media content sources and identify the monitored media content.

An article of manufacture storing machine readable instructions which, when executed, cause a machine to:

• determine first information based on a video signal corresponding to monitored media content provided by a selected one of a plurality of media content sources for presentation by an information presenting device;
• determine second information based on an audio signal corresponding to the monitored media content;
• identify the selected one of the plurality of media content sources based on a first classification decision resulting from one of the first information and the second information and a second classification decision resulting from the other of the first information and the second information;
• and
• identify the monitored media content based on identification information associated with at least one of the video signal or the audio signal.