Small changes in a broadcast version of a base media item can be identified by performing a multi-level comparison of digital fingerprints. A fingerprint of a base media item is compared to a fingerprint of a media broadcast to determine whether a media item embedded in a broadcast is likely, to a first level of certainty, to be the base media item. A second, more stringent, match between the fingerprint of the base media item and loosely matched items can be used to identify potentially-altered versions of the base media item. Potentially-altered versions can be compared against each other, and resulting matches are flagged as altered base media items, which can be fingerprinted and tested against broadcast fingerprints in the same manner as the base media item. Comparisons are made in parallel between two fingerprints to distinguish between a known base media item and unknown altered versions of the known base media item without prior storage of the unknown altered versions of the known base media item.

A method and system for providing contextual filters respective of an identified context of a plurality of multimedia content elements are provided. The method comprises receiving the plurality of multimedia content elements; generating at least one signature for each of the plurality of multimedia content elements; determining a context of each of the plurality of multimedia content elements based on its respective at least one signature, wherein a context is determined as the correlation among a plurality of cluster of signatures; and providing at least one contextual filter respective of the context of each of the plurality of multimedia content elements.

A method for signature-enhanced multimedia content searching. The method includes searching through a plurality of input multimedia content elements by comparing a query to at least one tag assigned to each input multimedia content element, wherein at least one of the at least one tag assigned to each input multimedia content element is assigned based on at least one signature generated for the input multimedia content element, wherein each signature represents a concept, wherein each concept is a collection of signatures and metadata representing the concept.

A method and system for providing recommendations to multimedia content elements of interest to a user. The method comprises receiving at least one multimedia content element; generating at least one signature for the received multimedia content element; querying a user profile of the user to determine a user interest; searching, by means of the at least one generated signature, through a plurality of data sources for multimedia content elements matching the determined user interest; and returning the matching multimedia content elements to the user node as recommendations.

A system and method for identification of inappropriate multimedia content elements are provided. The method includes receiving a request to identify a multimedia content element from a user device; generating at least one signature respective of the received multimedia content element; matching between the at least one of generated signature respective of the multimedia content element and at least one signature of each concept designated as inappropriate; determining whether a match is identified between the at least one of signature generated respective of the multimedia content element and the at least one signature of an inappropriate concept; and preventing the display on a user device of the multimedia content element, upon identification of a match.

Methods and apparatus to determine a state of a media presentation device are disclosed. Example disclosed methods include generating a first set of weighted coefficients based on first audio received by first and second microphones at a first time. Example disclosed methods include generating a second set of weighted coefficients based on second audio received by the first and second microphones at a second time after the first time. Example disclosed methods include comparing the first set of coefficients and the second set of coefficients to generate a similarity value. Example disclosed methods include, when the similarity value satisfies a threshold, determining that the media presentation device is in a first state. Example disclosed methods include, when the similarity value does not satisfy the threshold, determining that the media presentation device is in a second state.

A method and system for providing at least a link to a content item related to a multimedia content element respective of an on-image gesture. The method comprises receiving, from a user device, at least on-image gesture and the multimedia content element; analyzing the at least on-image gesture determine at least one portion of the multimedia content element that a user is interested in; generating at least one signature for each of the at least a portion; determining a content item corresponding to the at least one identified portion of multimedia content, wherein the determination is based in part on a type of the at least on-image gesture; and modifying the received multimedia content element to include at least a link to an informative resource containing the content item.

A system and method for clustering multimedia content. The method includes: detecting at least one clustering trigger event related to at least one multimedia content element to be clustered; generating at least one signature for the at least one multimedia content element, each signature representing at least a portion of the at least one multimedia content element; determining, based on the generated at least one signature, at least one multimedia content element cluster, wherein each multimedia content element cluster includes a plurality of clustered multimedia content elements sharing at least one common concept with the at least one multimedia content element; and adding, to each determined cluster, the at least one multimedia content element.

A system and method for identifying multimedia content elements are presented. The method includes generating a signature for an unknown multimedia content element (MMCE), wherein the unknown MMCE is a portion of a multimedia content item; comparing a signature of the unknown MMCE to a signature cluster of at least one concept to determine whether each of the at least one concepts is proximate to the unknown MMCE; for each proximate concept, determining a probability that the at least one proximate concept identifies the unknown MMCE; and identifying the MMCE based on the determined probabilities of the at least one proximate concept.

Methods and apparatus for determining whether a media presentation device is in an on state or an off state are disclosed. A disclosed example method comprises determining contribution values from at least one of a signal measured from a sensing device or an output signal accessed from the presentation device, wherein the contribution values are indicative of a state of a presentation device. Summing, via a logic circuit, a first plurality of the contribution values corresponding to a first measurement cycle to generate a first intermediate fuzzy score for the first measurement cycle. Storing the first intermediate fuzzy score in a buffer including a plurality of intermediate fuzzy scores corresponding to respective measurement cycles. Combining, via the logic circuit, the intermediate fuzzy scores corresponding to a first time period to form a final fuzzy score. When the final fuzzy score satisfies a threshold, setting the state of the presentation device as on and enabling crediting of media presented by the presentation device.