Subject: Wavelets .vs. JPEG

From: [email-masked] (Steven D. Majewski)
Date: Mon, 24 Jun 91 23:26:04 GMT

I will not defend this quote.I merely offer it up for discussion.
( I can't defend it: I don't know anything about wavelets, although
 I will immediately look up one of the references he mentions: 
   Daugman, John, ENTROPY REDUCTION AND DECORRELATION IN VISUAL CODING
   BY ORIENTED NEURAL RECEPTIVE FIELDS, in IEEE Transactions on 
   Biomedical Engineeringm Vol 36, no 1, Jan '91 ) 
 No offense intended to all of the people so diligently working on the
 PD JPEG implementation, from whom I have learned most of what I know 
 about JPEG compression.  
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______________________________________________________________________
>from Don Lancaster's HARDWARE HACKER column in the 
 JULY '91 RADIO ELECTRONICS magazine:
_______________________________________________________________________
  "At any rate, an awful lot of people have spent an awful lot of time
 and money to make the DCT a major new video compression standard. 
 Even PostScript Level II now has build-in DCT filters, and dozens of 
 firms are offering or about to offer DCT compression solution."
  "The only little problem here is that the wavelet transforms pass the
 DCT like it was sitting up on blocks. It appears that anything that the 
 DCT can handle, wavelets can do faster, cheaper, better, and with far
 fewer objectionable artifacts."
  "In particular, there are background "tiling" effetcs using the DCT, but
 none using wavelets. Your wavelet transform computations are quite simple,
 ane much easier to realize in standard or near-standard hardware. Wavelets
 are also good at building up the "big limps" first, followed by finer detail.
 That gets important in a rapidly changing video scene." 
  "So, I guess we are going to shortly see the answer to the question "What
 happens when a bunch of people spend lots of time and effort creating a
 new standard that is clearly and ludicrously obsolete before the ink on 
 the final version is dry?" stay tuned on this one."

( * DCT = Direct Cosine Transform; one step of the JPEG compression scheme. ) 

======== "If you have a hammer, find a nail" - George Bush,'91  =========
 Steven D. Majewski             University of Virginia Physiology Dept.
 [email-masked]             Box 449 Health Sciences Center
 Voice: (804)-982-0831          1600 Jefferson Park Avenue
 FAX:   (804)-982-1616          Charlottesville, VA 22908