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 35C053EF45 for ; Mon, 19 Nov 2001 12:03:23 -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 fAJH3Mp01499 for ; Mon, 19 Nov 2001 12:03:22 -0500 Received: (from mail@localhost) by mail.redhat.com (8.11.0/8.8.7) id fAJH3MZ09722 for blinux-list@listman.redhat.com; Mon, 19 Nov 2001 12:03:22 -0500 Received: from sun8.loc.gov (sun8.loc.gov [140.147.249.48]) by mail.redhat.com (8.11.0/8.8.7) with ESMTP id fAJH3Mw09718 for ; Mon, 19 Nov 2001 12:03:22 -0500 Received: from lras (lras.loc.gov [140.147.40.26]) by sun8.loc.gov (8.8.8+Sun/8.8.8) with SMTP id MAA24836 for ; Mon, 19 Nov 2001 12:03:09 -0500 (EST) Message-Id: <3.0.5.32.20011119120413.00874d50@sun8.LOC.GOV> X-Sender: LRAS@sun8.LOC.GOV X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.5 (32) Date: Mon, 19 Nov 2001 12:04:13 -0500 To: blinux-list@redhat.com From: "Lloyd G. Rasmussen" Subject: Re: Digital Talking Book Standard In-Reply-To: <20011119174322.D29158@stalin.acc.umu.se> References: <20011119172716.B29158@stalin.acc.umu.se> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" 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: In the NISO standard, we're not allowing variable bit rate, for the reasons outlined below. I haven't seen huge space savings for voice recordings. At 05:43 PM 11/19/01 +0100, you wrote: >On Mon, Nov 19, 2001 at 11:35:59AM -0500, Nicolas Pitre wrote: >> On Mon, 19 Nov 2001, Peter Toneby wrote: >> >> > On Mon, Nov 19, 2001 at 11:14:39AM -0500, Janina Sajka wrote: >> > > What about freeamp? >> > >> > It does not support searches on timecode (at least I didn't see anything >> > about that while checking their pages, they only seem to have normal >> > seek in files, which is not enough). >> >> Well... It is enough with some extra processing. You need to find out the >> data bitrate, estimate the seek position in the audio file, resynchronize on >> a mpeg frame boundary, back a couple frames, compute the backed frames to >> restabilize the mpeg windowing factors without actually playing them then >> finally resume audio from the desired frame. > >The problem is VBR, I'm not sure how it works, but I suspect each frame >have it's own bitrate in that case, and if the stream use that, you need >to loop through all frames and calculate the current time :(, well, I'll >have a closer look at mad and see if I can do something for fixed >bitrates at least. > >/Peter Braille is the solution to the digital divide. Lloyd Rasmussen, Senior Staff Engineer National Library Service f/t Blind and Physically Handicapped Library of Congress (202) 707-0535 HOME: