Method and apparatus for enhanced phonetic indexing and search

A method comprising:

• receiving digital representations of audio signals, wherein the audio signals are produced by a suitable device;
• producing phonetic indexes of the audio signals based on said digital representations thereof;
• producing phonetic N-gram sequences from the phonetic indexes by segmenting the phonetic indexes into a plurality of phonetic N-grams;
• producing inverted indexes of the plurality of phonetic N-grams;
• obtaining a textual search term;
• converting the textual search term into a phonetic search term;
• searching the phonetic search term on the inverted indexes;
• ranking the digital representations of the audio signals based on matching between the search query and detected events of the search in the inverted indexes such that a rank reflects the probability that the textual search term is found within any of the audio signals,
• wherein the ranking is according to the following formula:
• Rank
• j
• =
• 100
• *
• (
• 1
• -
• a
• *
• log
• 2
• (
• 1
• +
• 1
• ∑
• i
• =
• 0
• N
• -
• 1
• ⁢
• C
• i
• )
• )
• where the rank is the rank level, j denotes the audio signal, Cj is the confidence score of i-th detected event that satisfy a query in the j-th signal, N is the number of detected events within the j-th signal that satisfy the search query, and a is a constant;
• and
• based on the ranking, determining whether or not to automatically perform on each signal of the audio signals a second slower and more accurate phonetic search based on non-inverted indexing,
• in case a determination to perform the second search is satisfied then the second slower and more accurate phonetic search based on non-inverted indexing is carried out;
• responsive to performing the second slower and more accurate search, determining search results with respect to the textual search term;
• and
• playing back, via a media player, the search results with respect to said digital representations of the audio signals.