mikejuk (1801200) writes "The Microsoft Research Audio Video Indexing System (MAVIS) has been running on a trial basis for a while and it extends search to audio material. It uses speech recognition to transcribe audio sources and then indexes them for use by standard search engine.
Not only does this let you search audio recordings but video sound tracks as well. There is also an API that means it can be built into other applications.
Of course being able to index audio files is just one step away from being able to index phone calls in the same way...."
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