3. The device of claim 1 , wherein the operations further comprise: detecting a second occurrence of the textual phrase in the closed captioning as a detected second occurrence; obtaining a second audio segment corresponding to the textual phrase as a second selected audio segment; and computing a second phonetic transcription for the second selected audio segment as a second computed transcription.
5. The device of claim 3 , wherein the operations comprise adding the second audio segment to the speech recognition library in relational association with the textual phrase.