How would you react if the voice of a record-company boss boomed through your speakers and berated you for pirating music? You may find out, if the music industry decides to adopt an invention by Mark Bocko and Zeljko Ignjatovic of New York city.
With help from the US Air Force Research Laboratory, the inventors found they could bury around 20 kilobits of speech data in a song without affecting how it sounds (US patent application 2005/0033579). Their technique exploits the fact that the tones of a musical instrument are made up of a complex pattern of randomly phased harmonics.
By forcing a few of these harmonics to move in and out of phase with a chosen reference, they can be made to convey a digital message. These phase shifts are so small they are imperceptible to the ear. But a software decoder, which could be built into MP3 players or file-sharing applications, detects the phase shifts and turns them into speech.
LONGER-LIFE DIGITAL SNAPS
Digital snapshots printed out on ink-jet photo paper seldom look as vivid as professional prints, especially after a few weeks. The problem is not with the ink, but the paper, says Eastman Kodak (US 2005/0013945).
Ink-jet paper has to be porous so the alcohol-based ink dries quickly and leaves the surface smudge free. But oxygen and ozone from the air also get into the paper and make the dye fade.
Kodak's answer is to coat the paper with 0.5-micrometre-wide silica spheres that have been roughened by exposing them to a high-voltage discharge. This roughness helps an aluminosilicate polymer coating stick fast to the beads. The coating lets the alcohol-based ink through to the silica, but slows down the absorption of gases from the air.
Kodak tested the paper on an Epson printer and found a that a brightly coloured image stayed vivid for some months - even when subjected to artificially high levels of ozone.
Story source:
newscientist.com.
