New pending patent applications are published by the USPTO on Thursdays. Both of today's Spotlight Applications concern aspects of digital fingerprinting. Assigned to Shazam, the first application discloses techniques for recognizing sound and music signals in high noise and distortion. Assigned to Yandex Europe, the second application discloses techniques for indexing audio tracks using chromaprints.
20160328473, "Systems and methods for recognizing sound and music signals in high noise and distortion," assigned ot Shazam.
A method for recognizing an audio sample locates an audio file that closely matches the audio sample from a database indexing a large set of original recordings. Each indexed audio file is represented in the database index by a set of landmark timepoints and associated fingerprints. Landmarks occur at reproducible locations within the file, while fingerprints represent features of the signal at or near the landmark timepoints. To perform recognition, landmarks and fingerprints are computed for the unknown sample and used to retrieve matching fingerprints from the database. For each file containing matching fingerprints, the landmarks are compared with landmarks of the sample at which the same fingerprints were computed. If a large number of corresponding landmarks are linearly related, i.e., if equivalent fingerprints of the sample and retrieved file have the same time evolution, then the file is identified with the sample.
20160328472, "Method of and a system for indexing audio tracks using chromaprints," assigned to Yandex Europe AG (CH)
A non-transient computer information storage medium storing an audio track inverted index, and method of its creating and maintaining, the audio track inverted index comprising a plurality of sets of posting lists, each posting list within the plurality of sets of posting lists being a posting list of chroma words, each chroma word being a component of an audio fingerprint, each of chroma words being split into a plurality of bytes, each of chroma words comprising a beginning portion of the chroma word, the beginning portion of the chroma word being a sub-plurality of bytes having a first byte and a following byte, the following byte located immediately after said first byte; within a given set of posting lists of the plurality of postings lists: each posting list contains chroma words having the same first byte within the beginning portion of the chroma word, and a first one of the plurality of posting lists being different from a second one of the plurality of posting lists by the associated chroma words having a different following byte, the different following byte being unique for the given set of posting lists. Validation index comprising key file and fingerprint file.