BlueSpike specializes in digital watermarking technologies in order to "preserve creators' custody of their works and yet maintain the balance of interests between creators, distributors, and consumers as defined under copyright law." BlueSpike's signature product is a watermarking program called Giovanni.
Giovanni is a genuine digital watermarking system. This patented system provides a means for creators of multimedia content to protect their copyrights on computer networks or other digital media such as compact discs, as well as track content that is electronically distributed. Giovanni can be simply differentiated from other digital watermark systems by its use of "keys" in the watermark process. These keys are separate from the actual encoding and decoding process. Essentially, Giovanni allows copyright holders to create encoded messages, break them up into single bits, and plant them in random locations in a signal. Those bits are locatable only by the same key that was used to place the bits of the watermark payload.
All digital samples have a built-in allowance for error, because they are only approximations of an analog signal. Even if the digital data is badly damaged, it is still often recognizable when played or viewed.
Giovanni binds a digital signature to a recorded music digital signal in a manner that ensures that attempts at erasure cause audible damage to the song. Secure BlueSpike watermarks can be used to tamperproof individual instances of a digital copy of any media content.
For watermarking, not just encryption, encoding and encryption are handled by the key as well. The private key is used to encode the digital watermark into the music. The public key is used to decode the digital watermark from the music without revealing the private key. The consumer can even authenticate a copy of a song with a public key, just like a purchase receipt.
Giovanni watermarks can be both a digital signature and a digital fingerprint. In a similar manner to encryption, Giovanni can use digital signatures. The process of embedding a watermark into a digital sample stream is not a digital signature calculation, as is executed in public key cryptographic systems. The information encoded by Giovanni is digitally signed, however, to certify the validity of the information when it is extracted. In so-called asymmetric or public-key cryptography, a file encoded with the "private" key of a user's key pair can only be decoded with a correlative "public" key.
Giovanni watermarks can be applied to any data consisting of digitized samples, such as digital audio, video, and still images. The watermarks can also be completely removed with an authorized key. Giovanni watermarks are also able to survive analog conversions in both audio and still images.
More information can be found at www.bluespike.com.