Research into digital technology, undertaken so far by various companies around the world, has developed various means of watermarking data in digital formats, such as on CDs, MiniDisc, DAT and sampled sound files . The idea is to embed a code within the audio signal (or on the image of a video on CD -ROM) which can be recovered using the appropriate technology, without affecting the quality of the product. Only a small amount of the total data of the track is allocated to the watermark - if one second of stereo digital audio is represented by 1,411,200 bits, the maximum throughput of most commercially-available watermarking processes amounts to only 0.001417% of the total (assuming that the watermark is present throughout the track).
Since the watermark is an integral part of the recording, it cannot be removed without seriously damaging the sound quality. Since the digital watermark is inaudible, any information can be contained therein, including names of the song, artist, writers, album, record company etc. The code (or datastream) embedded in the audio could also contain information regarding the e-mail address and identity of the person who downloaded the track and the serial number of the audio recorder used in the transaction.
There are several applications of this technology which are of benefit to the music industry -
Previous: Digital audio watermarking | Contents | Next: Royalty collection / broadcast monitoring