Return-Path: Received: from atl4mhob15.myregisteredsite.com ([209.17.115.53] verified) by media-motion.tv (CommuniGate Pro SMTP 4.2.10) with ESMTP id 5169444 for AE-List@media-motion.tv; Thu, 08 Aug 2013 14:43:08 +0200 Received: from mailpod.hostingplatform.com ([10.30.71.210]) by atl4mhob15.myregisteredsite.com (8.14.4/8.14.4) with ESMTP id r78CsqC0031622 for ; Thu, 8 Aug 2013 08:54:52 -0400 Received: (qmail 7250 invoked by uid 0); 8 Aug 2013 12:54:52 -0000 X-TCPREMOTEIP: 60.225.197.206 X-Authenticated-UID: chris@chriszwar.com Received: from unknown (HELO ?192.168.0.3?) (chris@chriszwar.com@60.225.197.206) by 0 with ESMTPA; 8 Aug 2013 12:54:52 -0000 Content-Type: text/plain; charset=iso-8859-1 Mime-Version: 1.0 (Mac OS X Mail 6.5 \(1508\)) Subject: Re: [AE] rendering issue From: Chris Zwar In-Reply-To: Date: Thu, 8 Aug 2013 22:54:48 +1000 Content-Transfer-Encoding: quoted-printable Message-Id: References: To: "After Effects Mail List" , Jeanette Barekman X-Mailer: Apple Mail (2.1508) On 08/08/2013, at 10:08 AM, Jeanette Barekman = wrote: > Would like to know what are the pluses for using an AC3 file. AC3 is the Dolby Digital codec used on DVDs. It's a compressed format, = in the same way that MP3s and AAC (iTunes) are compressed files, however = AC3 was specifically designed for 5.1 surround sound. It supports a = range of channels - including stereo and 5.1 - and the bitrate can be = adjusted to balance file size and quality. On DVDs it's always 48K, but = I think in software it can handle different sample rates. WAV and AIFFs are uncompressed files, taking up roughly 600meg for 1 = hour of stereo audio. If a DVD used uncompressed audio then a 2 hour = feature film with 5.1 surround sound would need 3.6 gig just for the = audio tracks, which is pretty pointless as a single layer disc only = holds 4.3 gig in total. On paper DVDs support a few different types of audio, but in general AC3 = IS the DVD audio standard. Commercial DVDs that don't use AC3 for audio = are extremely uncommon. -Chris