Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!goblin2!goblin.stu.neva.ru!newsfeed.xs4all.nl!newsfeed3.news.xs4all.nl!xs4all!post.news.xs4all.nl!not-for-mail Return-Path: X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: OK 0.013 X-Spam-Evidence: '*H*': 0.97; '*S*': 0.00; 'assuming': 0.09; 'etc).': 0.09; 'integers': 0.09; 'cc:addr:python-list': 0.11; 'wrote': 0.14; 'random': 0.14; 'assumptions': 0.16; 'carefully.': 0.16; 'from:addr:pobox.com': 0.16; 'from:addr:skip': 0.16; 'means.': 0.16; 'tennis': 0.16; 'language': 0.16; 'sender:addr:gmail.com': 0.17; 'wrote:': 0.18; '(not': 0.18; 'wed,': 0.18; 'select': 0.22; 'aug': 0.22; 'cc:addr:python.org': 0.22; 'cc:2**1': 0.23; 'skip': 0.24; 'math': 0.24; 'looks': 0.24; "i've": 0.25; 'header:In-Reply- To:1': 0.27; 'message-id:@mail.gmail.com': 0.30; '13,': 0.31; 'everyone': 0.33; 'problem': 0.35; 'received:google.com': 0.35; 'add': 0.35; 'like,': 0.36; 'pm,': 0.38; 'read': 0.60; 'solve': 0.60; 'most': 0.60; 'challenge': 0.61; 'simple': 0.61; 'to:addr:gmail.com': 0.65; 'sample': 0.67; 'cultural': 0.74; 'square,': 0.84; 'visually': 0.84; 'joel': 0.91 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:date:message-id:subject :from:to:cc:content-type; bh=L4rTU2EkDEJKK46mRXah3GIHxkrOam4PmrvrG9Rk9zs=; b=y2sClgeOtILSDRQaQLkgKVsGiwyDL/jNts+GCGfi/bxUKnhjrnN59oyYPNvNuRYUDc lBbSa378a5cbUIboe9LHnRvHYrwI81mtiQ9VWTHaMP2hULj+9OrjMq3Q6dqblCc4QC8I IqF0rWt2A0g6hKVV50pK16rzcmZchNMPlCEhZktS/lHCi4/4CoNu3gApWiKKRY1yyW+h B7LENuoK7Hq2MDH+qRFUIqYVIrjQ/g7BbAFJr1OHWxu27g95hu5uEPjkxbiICmb0ZEay UGEsJZOoySXvTjS5VUQ+R+1Q9Pdut0dJh5e6IR6QOCQkLqK5T7RiEAoqIAWUOpgjZJso YVhA== MIME-Version: 1.0 X-Received: by 10.42.82.6 with SMTP id b6mr8891003icl.51.1407959701805; Wed, 13 Aug 2014 12:55:01 -0700 (PDT) Sender: skip.montanaro@gmail.com In-Reply-To: References: <8c2e4bc2-4f46-4a68-83ed-469fe171de3a@googlegroups.com> <2320baf0-e097-4d67-97c1-dd37ca79fffb@googlegroups.com> <376a239c-77e8-4e0e-9300-847dfa8a8547@googlegroups.com> <53EB4E68.8050405@harvee.org> Date: Wed, 13 Aug 2014 14:55:01 -0500 X-Google-Sender-Auth: YRNPtMstI60dP2CS1Oaufe2opCQ Subject: Re: Captcha identify From: Skip Montanaro To: Joel Goldstick Content-Type: text/plain; charset=UTF-8 Cc: "python-list@python.org" X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: General discussion list for the Python programming language List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Newsgroups: comp.lang.python Message-ID: Lines: 16 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1407959710 news.xs4all.nl 2963 [2001:888:2000:d::a6]:42397 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:76233 On Wed, Aug 13, 2014 at 2:44 PM, Joel Goldstick wrote: > I wrote a sample form page with a simple math problem to solve -- 2 or > 3 random small integers to add ... I've also seen challenge systems where they present you with a small set of images and ask you to select one with a particular property (looks like a tennis racquet, shaped like a square, etc). While simple to solve for most humans -- assuming they can read the language -- they would be difficult to solve by automated means. You can also magnify them for visually impaired or speak what they are on rollover/hover, and don't require any typing. They can make cultural assumptions (not everyone will know what a tennis racquet looks like, for instance), so the images might have to be selected carefully. Skip