Watermark Patent Awarded
The company says, "This newly patented invention covers a technique for embedding and detecting watermark data within an audio signal in a computationally efficient way. The optimum level for the watermark signal is determined using mathematical algorithms that require significantly less processing power than other techniques. This greatly increases the watermark decoder's ability to detect the watermark inside recorded music."
The new watermark patent is for one of several music distribution technologies developed by Liquid Audio. The company was awarded a patent last December for a territory restriction technology, which enforces regional copyrights by determining a user's location based on the geopolitical territory of the user's Internet Protocol (IP) address (see previous story).
In addition to its last watermark patent, last April Liquid Audio revealed that it had received another patent (#6,209,094) covering a technique for embedding watermark data in an audio signal that, the company states, is robust and cannot be removed without destroying the music. LA also claims that the watermark is "imperceptible and cannot be heard by the music listener."