Subject: Information loss (Re: Analytical approach to temporal coding...) From: Dan Ellis <dpwe(at)EE.COLUMBIA.EDU> Date: Sat, 24 Feb 2001 05:43:58 -0500It's an interesting question to figure out the constraints imposed by the AN spike representation and how much of the original sound waveform information is available to subsequent processing. But if the answer is "all of it" (as I understand Ramdas Kumaresan's post to be arguing), that's actually, for me, a disappointing result. The function of auditory scene analysis -- and audition in general -- is to extract *useful* information (defined according to the goals of the organism), and throw away the rest. It may be that, ultimately, the cochlea doesn't contribute much to this higher-level processing i.e. it is obliged to provide a near-complete representation because the useful selection between relevant and irrelevant detail can't be implemented at such a low level of analysis. But for me the real interest lies in finding the representations that *do* throw away information, that sacrifice the ability to make full reconstructions, then seeing which parts are kept. That't the kind of description we need to help us build intelligent automatic sound analysis systems. -- DAn Ellis <dpwe(at)ee.columbia.edu> http://www.ee.columbia.edu/~dpwe/ Dept. of Elec. Eng., Columbia Univ., New York NY 10027 (212) 854-8928