New patents are issued by the USPTO on Thursdays. Today's Spotlight Patents concern aspects of digital watermarking and digital fingerprinting. Assigned to Orange (FR), the first patent addresses techniques for watermarking a sequence of images and for authenticating a sequence of watermarked images. Assigned to Hitachi, the second patent addresses techniques for accurate and efficient detection of data duplication.
9,239,966, "Method and device for watermarking a sequence of images, method and device for authenticating a sequence of watermarked images and corresponding computer program," assigned to Orange (FR)
A method for watermarking a sequence of images is provided. The method implements the following steps, for at least one current image: comparing the current image with a preceding image of the sequence, delivering a difference image representing a motion between the preceding image and the current image; if the difference between the current image and the preceding image is above a predetermined threshold, watermarking the current image by inserting a message comprising a field carrying an identifier of the current image and a field carrying a soft hash obtained from at least one portion of the difference image; and if not, watermarking the current image by inserting a message comprising a field carrying an identifier of the current image.
9,239,844, "Data duplication detection system and method for controlling data duplication detection system," assigned to Hitachi (JP).
Accurate and efficient detection of data duplication is implemented. A data duplication determination part (1A) of a storage system (1) temporarily stores in a pool (4) a target chunk data when a second management table (T2) indicates that the target chunk data, which is included in received data, has already been stored, and, in addition, when data (a fingerprint (FP)) for guaranteeing the identity of the target chunk data is not stored in a third management table (T3). The duplication determination part (1A), in a case where the second management table indicates that another target chunk data that differs from the target chunk is already stored, and, in addition, in a case where determination is made that the FP of the other target chunk data is stored in the third management table, makes a redetermination as to whether the chunk data stored in the pool has already been stored.