Methods and systems for decreasing latency of content recognition

1. A method for reducing latency in identification of an audio work in an audio stream received in an audio recognition system, the method comprising:

receiving, in a reference-fingerprint generator, a reference audio content associated with an audio work;

generating, in the reference-fingerprint generator, a modified reference audio content by prepending a selected audio content to the reference audio content;

computing, in the reference-fingerprint generator, at least one modified-reference fingerprint from the modified reference audio content using an analysis window comprising a portion of the prepended, selected audio content;

storing, in a database communicatively coupled to the reference-fingerprint generator, the at least one modified-reference fingerprint;

receiving, in an audio recognition system, an audio stream;

sampling, in the audio recognition system, the audio stream in real time;

computing, in the audio recognition system, at least one fingerprint from the samples of the audio stream;

comparing, in the audio recognition system, the at least one fingerprint generated from the samples of the audio stream with the at least one modified-reference fingerprint stored in the database; and

when a first fingerprint from the at least one fingerprint generated from the samples of the audio stream substantially matches a second fingerprint from the at least one modified-reference fingerprint, identifying that the audio stream comprises the audio work.

2. The method of claim 1 , wherein the selected audio content does not produce a fingerprint match with the reference audio content.

3. The method of claim 1 , wherein the selected audio content comprises a fixed duration of a pink noise.

4. The method of claim 1 , wherein the selected audio content comprises a fixed duration of a low-frequency tone.

5. An audio recognition system for identifying an audio work in a received audio stream, the system comprising:

a reference-fingerprint generator module configured to receive a reference audio content associated with an audio work, to modify the reference audio content by prepending a selected audio content to the reference audio content and to generate at least one modified-reference fingerprint from the modified reference audio content using an analysis window comprising a portion of the prepended, selected audio content;

a database module configured to store the at least one modified-reference fingerprint;

a sampler module configured to receive an audio stream and to extract samples, in real time, therefrom;

a buffer module configured to store the extracted samples of the audio stream;

a fingerprint generator module configured to generate at least one sample fingerprint from the stored samples of said audio stream; and

a fingerprint comparator module configured to compare two fingerprint, wherein one of the two fingerprint is a fingerprint from the at least one modified-reference fingerprint and the other of the two fingerprints is a fingerprint from the at least one sample fingerprint and to detect a match between at least a portion of said two fingerprints, thereby identifying that the audio stream comprises the audio work.

6. The system of claim 5 , wherein the selected audio content does not produce a fingerprint match with any reference audio content.

7. The system of claim 5 , wherein the selected audio content comprises a fixed duration of a pink noise.

8. The system of claim 5 , wherein the selected audio content comprises a fixed duration of a low-frequency tone.