Sony and Toshiba Watermarking Patents

On Tuesdays the USPTO issues new patents. Both of today's Spotlight Patents address various aspects of watermarking. Assigned to Sony, the first patent concerns techniques for data recording that employ watermarking. Assigned to Toshiba, the second patent concerns techniques for detecting digital watermarks.

7,436,959, "Data recording apparatus and recording method," assigned to Sony (JP).

Abstract

A data recording and/or reproducing device is provided having a deciphering circuit, a detection circuit, a data processing unit, a recording unit and a controller. The deciphering processing unit deciphers and/or decompresses input encrypted and/or compressed data. The detection circuit detects whether or not watermark signals are contained in output data of the deciphering processing unit. The data processing unit is supplied at least with output signals from the deciphering processing unit and applies signal processing for recording on the supplied data. The recording unit records output data from the data processing unit on a recording medium. If the watermark signals are detected to be contained by the detection unit, the controller controls the operation of the data processing unit based on the detected watermark signals. 

7,437,564, "Digital watermark detection method and apparatus," assigned to Toshiba (JP).

Abstract

A specific frequency component extraction unit extracts a specific frequency component signal from an input image signal. A phase controller controls the phase of the specific frequency component signal. A correlator computes the cross-correlation value of the phase-controlled specific frequency component signal and the input image signal. A watermark information estimation unit filters the cross-correlation value to detect watermark information embedded in the input image signal.