New patents are issued by the PTO on Tuesdays. Both of today's Spotlight Patents concern aspects of digital watermarking. Assigned to Cisco, the first of today's patents addresses techniques for audio watermarking. Assigned to Sony (JP), the second patent addresses techniques for recording/playing audio data having additional information embedded therein.
8,762,146, "Audio watermarking," assigned to Cisco.
A system, including a processor to define opportunities for encoding a watermark into an audio stream having sections, each section, when represented in the frequency domain, including a signal of amplitude against frequency, the processor being operative to, for each one of the sections, identify a fundamental frequency, f being the frequency with the largest amplitude of the signal in the one section, the fundamental frequency f defining harmonic frequencies, each harmonic frequency being at a frequency f/2n or 2fn, n being a positive integer, and define the one section as an opportunity for encoding at least part of the watermark if the amplitude of the signal of the one section is less than a value v for all frequencies in one or more different frequency ranges, each of the different frequency ranges being centered around different ones of the harmonic frequencies. Related apparatus and methods are also described.
8,756,709, "Apparatus for, and method of, recording/playing audio data having additional information embedded therein," assigned to Sony (JP).
According to the type of each of a plurality of external input interfaces, it is decided whether digital watermark information is to be detected from data entered via the external input interface. Digital watermark information is not detected from data entered via the external input interface and from which it has been decided not to detect any digital watermark information, but the data is recorded. Thus, there can be provided a data recording apparatus which is not applied with a any heavy load owing to the omission of any unnecessary detection of digital watermark information.