Source: http://www.labnol.org/internet/youtube-speech-recognition-called-google-audio-indexing/4551/
Sometime back, Google introduced speech recognition in YouTube that enables you to search for words spoken in the video and you could also directly jump to the portion where that word was said.
Initially you had to install an iGoogle gadget to experience YouTube’s speech recognition but now there’s a dedicated search page for this at Google Audio Indexing - this not just enables you to find spoken words in videos but also share that video portion.
If you like to share a clip where that word was found (or uttered), just click that ‘people’ icon in the YouTube Video player and you’ll get a direct link to that particular video segment.
http://labs.google.com/gaudi?q=obama&start=0&num=10&longId=-5906960400639115923
Like Blinkx, Google too has developed its own speech recognition system (called GAudi, for Google Audio Indexing), which powers both Google Audio Indexing and the Google Elections Video Search gadget.
Google Audio Indexing currently searches only videos related to US Elections that are uploaded on the YouTube political channels.
Google Speech Recognition Technology Is Now Called Google Audio Indexing - Digital Inspiration