From cinelerra-admin@skolelinux.no Sun Jun 1 04:46:32 2008 Return-Path: X-Original-To: cinelerra@e.kevb.net Delivered-To: cinelerra@e.kevb.net Received: from init.linpro.no (init.linpro.no [87.238.46.2]) by e.kevb.net (Postfix) with ESMTP id 697ABEC8028 for ; Sun, 1 Jun 2008 04:46:31 -0400 (EDT) Received: from localhost ([127.0.0.1] helo=init.linpro.no) by init.linpro.no with esmtp (Exim 4.50 #1 (Debian)) id 1K2jCW-0000MK-Fa; Sun, 01 Jun 2008 10:46:04 +0200 Received: from [81.191.93.201] (helo=hugo.mexico.debconf.org) (Authenticated Sender=herman@skolelinux.no) by init.linpro.no with esmtpa (Exim 4.50 #1 (Debian)) id 1K2jC6-0000Kx-Vc for ; Sun, 01 Jun 2008 10:45:39 +0200 To: cinelerra@skolelinux.no Subject: Re: [CinCV] Cinelerra doesn't recognize u-law audio on import? From: "Herman Robak" Content-Type: text/plain; charset=iso-8859-15 MIME-Version: 1.0 References: <611064.38720.qm@web35507.mail.mud.yahoo.com> Content-Transfer-Encoding: 7bit Message-ID: In-Reply-To: <611064.38720.qm@web35507.mail.mud.yahoo.com> User-Agent: Opera Mail/9.50 (Linux) X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on spamtrap X-Spam-Status: No, hits=-10.2 required=5.0 tests=DSPAM=-10.19694 version=2.63 X-Spam-Level: X-DSPAM-Signature: !DSPAM:48425d3c155428965610779! X-DSPAM-Probability: -2.0000 X-DSPAM-Confidence: 0.9997 X-Spam-Score: -1.4 (-) Sender: cinelerra-admin@skolelinux.no Errors-To: cinelerra-admin@skolelinux.no X-BeenThere: cinelerra@skolelinux.no X-Mailman-Version: 2.0.13 Precedence: bulk Reply-To: cinelerra@skolelinux.no List-Unsubscribe: , List-Id: Mailinglist for Cinelerra, the community version List-Post: List-Help: List-Subscribe: , List-Archive: Date: Sun, 01 Jun 2008 10:45:34 +0200 X-Spam-Score: -1.4 (-) On Sun, 01 Jun 2008 08:40:00 +0200, Spam Spam wrote: > Hey guys, it looks like the media I'm trying to load > is AVI with 8-bit ulaw audio, but Cinelerra thinks > it's 8-bit linear. As a result the audio is horribly > garbled and useless. Any idea how I can trick > Cinelerra into recognizing the right format? I would not recommend tricking here. ulaw uses a logarithmic sampling scale, to get a higher perceived resolution. I've read that it sounds equivalent to 12bit linear. Linear sampling has more detail that we can't hear. However, 16bit linear is good enough. And simple transforms like gain and fade are easy to perform without distortion. So I'd suggest converting the file to 16-bit linear audio. Logarithmic scales are fine when space is tight, and for end user distribution. It's less fun to deal with in processing. -- Herman Robak _______________________________________________ Cinelerra mailing list Cinelerra@skolelinux.no https://init.linpro.no/mailman/skolelinux.no/listinfo/cinelerra