Newsgroups: comp.dsp Path: utzoo!utgpu!cunews!wilf From: wilf@sce.carleton.ca (Wilf Leblanc) Subject: Re: 300 Baud Speech Vocoding... Message-ID: Sender: news@ccs.carleton.ca (news) Organization: Carleton University, Ottawa, Canada References: <1990Nov15.231800.119@xn.ll.mit.edu> Date: 16 Nov 90 03:05:42 GMT tj@xn.ll.mit.edu (Thomas E. Jones) writes: >I'm a little surprised no one has talked about the low data-rate >speech vocoding algorithms that have been developed. Me too. I thought with all the net bandwidth regarding compression to 'walkman' quality, someone would have brought this up. Maybe not walkman quality, but at least it is 'intelligable' (at a very low data rate). >[stuff deleted regarding segment vocoder @ 300 bps] There is alot of literature regarding 'vocoders' at 300 (or so) bps. Basically, most of them are an LPC vocoder (LPC10 type) with Vector Quantization of the LPC parameters and so on. See ICASSP around 1980-1984. Not (as) much written on it since then (to my knowledge). >A new vocoding algorithm known as Sinusoidal Coding has been >developed by the same group at Lincoln Lab., and offers much better voice >quality than LPC. Hmmmmm. Correct me if I'm wrong, but I thought Sinusoidal (Transform) coding was a (relatively) old technique which is becoming more popular due (mostly, if not entirely) to the work of McAuley and Quateri (my apologies if their names are spelled wrong, but this is on memory). >[.....] > - tj@xn.ll.mit.edu >-- >tj@xn.ll.mit.edu or tj@ll-xn.arpa (one of these should work) >Thomas E. Jones, home (617) 924-8326 work (617) 981-5093 -- --- Wilf LeBlanc Systems and Computer Eng. Internet: wilf@sce.carleton.ca Carleton University UUCP: ...!uunet!mitel!sce!wilf Ottawa, Ont, Canada