Watermark based content recognition improvements

A method for improving identification of a temporal or spatial location within a multimedia content based on detection of a watermark from a segment of the multimedia content, comprising:

• (a) receiving the multimedia content at a watermark extractor that is implemented at least partly in electronic circuitry;
• (b) using the watermark extractor to extract a plurality of candidate watermark symbols from the multimedia content that correspond to at least a portion of one or more embedded watermarks in the multimedia content and storing the extracted candidate watermark symbols in a non-transitory computer readable medium, wherein each of the one or more embedded watermarks has W symbols;
• (c) detecting a watermark synchronization pattern from the multimedia content, wherein the watermark synchronization pattern has H symbols and identifies start of a corresponding embedded watermark;
• (d) using the watermark extractor to extract k candidate watermark symbols from multimedia content subsequent to the detection of the watermark synchronization pattern, wherein k is selected to be a number this greater than or equal to 2 and less than W symbols;
• (e) retrieving W-H-k of the candidate watermark symbols from the non-transitory computer readable medium;
• (f) forming a candidate watermark by appending the retrieved W-H-k candidate watermark symbols to the H symbols of the watermark synchronization pattern and to the k candidate watermark symbols;
• (g) determining whether or not the candidate watermark forms a valid watermark;
• and
• (h) upon a determination that the candidate watermark forms a valid watermark, generating a signal that is indicative of a successful watermark detection.

A device, comprising:

• a processor;
• and
• a memory including processor executable code, the processor executable code, when executed by the processor, causes the device to:
• receive the multimedia content;
• extract a plurality of candidate watermark symbols from the multimedia content that correspond to one or more embedded watermarks in the multimedia content and store the extracted candidate watermark symbols in a non-transitory computer readable medium;
• process the extracted candidate watermark symbols to detect a synchronization header and to detect remaining symbols of a full watermark using the synchronization header;
• based on the detected full watermark, construct a first predicted watermark segment that includes a specific number of symbols and positioned at a first predicted distance from the synchronization header, the specific number being smaller than the number of symbols in the detected full watermark;
• retrieve, from the non-transitory computer readable medium, a group of candidate watermark symbols having the same number of symbols as the first predicted watermark segment and positioned at the same distance from the synchronization header as the first predicted distance;
• compare the group of candidate watermark symbols to the first predicted watermark segment;
• and
• upon a determination that a number of mismatched symbols between the group of candidate watermark symbols and the first predicted watermark segment is less than a first threshold value, generate a signal indicating that starting point of the group of candidate watermark symbols as a starting section of the watermarked segment within the multimedia content.

A device, comprising

• a processor;
• and
• a memory including processor executable code, the processor executable code upon execution by the processor, causes the device to:
• (a) receive the multimedia content;
• (b) extract a plurality of candidate watermark symbols from the multimedia content that correspond to at least a portion of one or more embedded watermarks in the multimedia content and store the extracted candidate watermark symbols in a non-transitory computer readable medium, wherein each of the one or more embedded watermarks has W symbols;
• (c) detect a watermark synchronization pattern from the multimedia content, wherein the watermark synchronization pattern has H symbols and identifies start of a corresponding embedded watermark;
• (d) extract k candidate watermark symbols from multimedia content subsequent to the detection of the watermark synchronization pattern, wherein k is selected to be a number this greater than or equal to 2 and less than W symbols;
• (e) retrieve W-H-k of the candidate watermark symbols from the non-transitory computer readable medium;
• (f) form a candidate watermark by appending the retrieved W-H-k candidate watermark symbols to the H symbols of the watermark synchronization pattern and to the k candidate watermark symbols;
• (g) determine whether or not the candidate watermark forms a valid watermark;
• and
• (h) upon a determination that the candidate watermark forms a valid watermark, generate a signal that is indicative of a successful watermark detection.

A computer program product, embodied on a non-transitory computer readable medium, for detecting one or more boundaries of a watermarked segment in a multimedia content, comprising:

• program code for receiving the multimedia content;
• program code for extracting a plurality of candidate watermark symbols from the multimedia content that correspond to one or more embedded watermarks in the multimedia content and storing the extracted candidate watermark symbols in a non-transitory computer readable medium;
• program code for, processing the extracted candidate watermark symbols to detect a synchronization header and to detect remaining symbols of a full watermark using the synchronization header;
• program code for, based on the detected full watermark, constructing a first predicted watermark segment that includes a specific number of symbols and positioned at a first predicted distance from the synchronization header, the specific number being smaller than the number of symbols in the detected full watermark;
• program code for, retrieving, from the non-transitory computer readable medium, a group of candidate watermark symbols having the same number of symbols as the first predicted watermark segment and positioned at the same distance from the synchronization header as the first predicted distance;
• program code for, comparing the group of candidate watermark symbols to the first predicted watermark segment;
• and
• program code for, upon a determination that a number of mismatched symbols between the group of candidate watermark symbols and the first predicted watermark segment is less than a first threshold value, generating a signal indicating that starting point of the group of candidate watermark symbols as a starting section of the watermarked segment within the multimedia content.

A computer program product, embodied on a non-transitory computer readable medium, for facilitating detection of a watermark from a segment of multimedia content, comprising:

• (a) program code for receiving the multimedia content;
• (b) program code for extracting a plurality of candidate watermark symbols from the multimedia content that correspond to at least a portion of one or more embedded watermarks in the multimedia content and storing the extracted candidate watermark symbols in a non-transitory computer readable medium, wherein each of the one or more embedded watermarks has W symbols;
• (c) program code for detecting a watermark synchronization pattern from the multimedia content, wherein the watermark synchronization pattern has H symbols and identifies start of a corresponding embedded watermark;
• (d) program code for extracting k candidate watermark symbols from multimedia content subsequent to the detection of the watermark synchronization pattern, wherein k is selected to be a number this greater than or equal to 2 and less than W symbols;
• (e) program code for retrieving W-H-k of the candidate watermark symbols from the non-transitory computer readable medium;
• (f) program code for forming a candidate watermark by appending the retrieved W-H-k candidate watermark symbols to the H symbols of the watermark synchronization pattern and to the k candidate watermark symbols;
• (g) program code for determining whether or not the candidate watermark forms a valid watermark;
• and
• (h) program code for, upon a determination that the candidate watermark forms a valid watermark, generation a signal that is indicative of a successful watermark detection.