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Sender: "piclist-bounces@mit.edu" Date: Tue, 6 Oct 2020 16:58:23 -0700 Subject: Re: [EE] Looking for technique to record audio after level exceeds some value Thread-Topic: [EE] Looking for technique to record audio after level exceeds some value Thread-Index: AdacPdFfFeP+OwGmRneJC+QmRpmbDA== Message-ID: <20201006235823.GA15413@laptop.org> References: List-Help: List-Subscribe: , List-Unsubscribe: , In-Reply-To: Reply-To: Microcontroller discussion list - Public. Accept-Language: en-US X-MS-Exchange-Organization-AuthAs: Anonymous X-MS-Exchange-Organization-AuthSource: TS500.efplus4.local X-MS-Has-Attach: X-Auto-Response-Suppress: All X-MS-Exchange-Organization-SenderIdResult: TempError X-MS-Exchange-Organization-PRD: mit.edu X-MS-TNEF-Correlator: received-spf: Pass (protection.outlook.com: domain of laptop.org designates 209.85.216.52 as permitted sender) receiver=protection.outlook.com; client-ip=209.85.216.52; helo=mail-pj1-f52.google.com; dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=laptop-org.20150623.gappssmtp.com; s=20150623; h=date:from:to:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=G7/j15rzmjFVXdMhT/H2rPtXfL2TH0wOoeR0YLh7F0Q=; b=lLxd3ifMz5Rfw3NAHymrNyS7Eoml0TP5y6Q+JDrpANQ+X7D+NHevirnwJrN/0/JxFH 4sX/ibtZG+BRoBniBFdLtSPY2DgbrZs2LgbcIfdUt8louPoGUeT+b+Ch4dRDRb8T/P1S puEutZvSpZZmLFc3KMeujpgpXz6o8mzHLgg2e/i5pjZHcwHa0D0KyTf5bFMQ29EqJDo7 pgXthefXt+z7UPItZ/dh+o43kaOECChjZ9QpvNeCgYyS3QnuPYhHYGOiv68lqXI+tHoI qCuXnToWW9mwD9a0z2w56QK6Q76606B66PIRQQ/y8hLRUZRGqsZX4nmYk6NtHFPFLmdf EbAA== authentication-results: spf=pass (sender IP is 209.85.216.52) smtp.mailfrom=laptop.org; mit.edu; dkim=pass (signature was verified) header.d=laptop-org.20150623.gappssmtp.com; mit.edu; dmarc=bestguesspass action=none header.from=laptop.org; user-agent: Mutt/1.9.4 (2018-02-28) errors-to: piclist-bounces@mit.edu list-id: "Microcontroller discussion list - Public." list-post: x-beenthere: piclist@mit.edu x-mailman-version: 2.1.6 x-received: by 2002:a17:902:b18f:b029:d2:1ec0:4161 with SMTP id s15-20020a170902b18fb02900d21ec04161mr528508plr.58.1602028709236; Tue, 06 Oct 2020 16:58:29 -0700 (PDT) x-topics: [EE] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 I once used an OLPC laptop to record every minute to a separate file and encode as MP3. It was a quick hack using Linux shell scripting. Then, to find the real-life event that I was looking for, I discarded the smallest files. The MP3 encoding meant that the real-life event audio consumed way more disk space than ambient silence audio. Lately I'm interested in bioacoustics recorders, to find the bird species on my property. It is a similar use case. --=20 James Cameron http://quozl.netrek.org/ --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .