From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from int-mx1.corp.redhat.com (int-mx1.corp.redhat.com [172.16.44.254]) by listman.redhat.com (Postfix) with ESMTP id 026873EA3A for ; Tue, 20 Nov 2001 11:16:13 -0500 (EST) Received: from mail.redhat.com (mail.redhat.com [199.183.24.239]) by int-mx1.corp.redhat.com (8.11.6/8.11.6) with SMTP id fAKGGCp10610 for ; Tue, 20 Nov 2001 11:16:12 -0500 Received: (from mail@localhost) by mail.redhat.com (8.11.0/8.8.7) id fAKGGC227826 for blinux-list@listman.redhat.com; Tue, 20 Nov 2001 11:16:12 -0500 Received: from dc.cis.okstate.edu (dc.cis.okstate.edu [139.78.100.219]) by mail.redhat.com (8.11.0/8.8.7) with ESMTP id fAKGGCw27822 for ; Tue, 20 Nov 2001 11:16:12 -0500 Received: from dc.cis.okstate.edu (localhost.cis.okstate.edu [127.0.0.1]) by dc.cis.okstate.edu (8.11.3/8.11.3) with ESMTP id fAKGGAa95386 for ; Tue, 20 Nov 2001 10:16:11 -0600 (CST) (envelope-from martin@dc.cis.okstate.edu) Message-Id: <200111201616.fAKGGAa95386@dc.cis.okstate.edu> To: blinux-list@redhat.com Subject: Re: Technical Question (was Digital Talking Book Standard ) Date: Tue, 20 Nov 2001 10:16:10 -0600 From: "Martin G. McCormick" X-Loop: blinux-list@redhat.com Sender: blinux-list-admin@redhat.com Errors-To: blinux-list-admin@redhat.com X-BeenThere: blinux-list@redhat.com X-Mailman-Version: 2.0.1 Precedence: bulk Reply-To: blinux-list@redhat.com List-Help: List-Post: List-Subscribe: , List-Id: Linux for blind general discussion List-Unsubscribe: , List-Archive: Yes, I am a bit slow, but I am catching on. I definitely need to understand more about time scale shifting methods and how to accomplish them without adding distortion. Each digit represents a moment in time and we can make things appear to speed up or slow down by intelligently inserting or deleting information. If we do it on a sample by sample basis, we can make the recording appear to speed up or slow down with the expected pitch changes. If we do it on a wave form by wave form basis, we can appear to keep the same pitch, but speed up the tempo or, for that matter, we can add extra wave forms and stretch out the syllables or whatever and slow them down. The old pitch correcting devices like the one I presently use to read magazines butcher the sound because they aren't smart enough to make sure the next snippet of sound starts at the same place on the wave form that the previous one ended so we get that characteristic gravelly sound at high rates. I usually run mine at maximum throttle so it is pretty bad, but with headphones, I can still understand it. Thanks to both of you for giving me some more food for thought. I may play some more with /dev/dsp and see what weird sounds I can come up with. Martin McCormick Janina Sajka writes: >Martin: > >It sounds like you're extrapolating from experience with analog systems >that achieve similar results. Fortunately, the science has become much >more sophisticated. I say that's fortunate because the results can be much >much better than those we've heard on analog tape decks.