On Tuesdays the USPTO issues new patents. Both of today's Spotlight Patents address aspects of digital watermarking. Assigned to TI, the first patent concerns techniques for image watermarking based on sequency and wavelet transforms. Assigned to Warner Brothers, the second patent concerns techniques to ensure that all audio-visual optical disc types are properly screened for watermarks.
7,742,619, "Image watermarking based on sequency and wavelet transforms," assigned to Texas Instruments.
This invention is a new approach for the image watermarking in the wavelet transform domain based on sequency of the host and watermark image. For each sub-band a first transform level of the host image is thresholded and binarized. Sequencies of thresholded and binarized data host image are compared with sequencies of the discrete wavelet transformed watermark image to form a watermarking sequency mask. The watermarked wavelet domain data is formed by combining data elements of the discrete wavelet transformed host image with corresponding data elements of the wavelet transformed watermark image as filtered by the watermarking mask. A reverse process can extract the watermark with a high degree of accuracy even after attack upon the watermarked host image.
7,747,875, "System to ensure that all audio-visual optical disc types are properly screened for watermarks," assigned to Warner Brothers Entertainment, Inc.
An apparatus for processing data and content includes at least one drive and a player (that may be implemented by software). At least some of the content is protected using a content scrambling scheme such as audio or video watermarking. The drive and player cooperate to operate in a lockable mode wherein if protected content is provided to the drive, the drive and player are interlocked so that the content is presented by the player only in accordance with consistent with protection scheme being used, and cannot be presented by any other player. Moreover, in the locked mode, protected content may not be accepted from any other drive. The drive and player are switched to an unlockded mode by presenting to the drive unprotected content.