They probably use wavelets (an extended sort of Fourier Transform).
Images (or sound or..) are represented in a hierarchical wavelet-structure that allows you to query it very rapidly for certain shapes or colors.
If you crawl the web and compute the wavelet-transformations of all the pictures you encounter, you have a very fast image query at your disposal.
Wavelets are also used by the FBI for instantly veryfying the identity of a person encountered on the road by sending the wavelet-transform of his fingerprint.
Slashdot Mirror
If you crawl the web and compute the wavelet-transformations of all the pictures you encounter, you have a very fast image query at your disposal.
Wavelets are also used by the FBI for instantly veryfying the identity of a person encountered on the road by sending the wavelet-transform of his fingerprint.
the Rio Karma sounds greatp lates/i tem_main_Rio.asp?model=220&cat=56
http://www.digitalnetworksna.com/shop/_tem
The following webpage mentions a few other ones
http://wiki.xiph.org/VorbisHardware