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关于recaptcha验证码

 

image

不知道大家经常见到这种验证码不

google和很多国外的网站都有采用它

个人觉得他很复杂,要输那么多单词才行.而且模糊不可辨识.

但是实际上这个验证码大有内涵

以下是一篇来自图书上的资料

image

如果我们要把他输入到电脑里面, 常用的是ocr

就是图形文字识别技术

但是上面这个已经比较模糊了

识别出来可能会是如下的情形

‘ letz-1- rrk fit: 1’ . on its to Vc ,rt, cann into tlm yc H_ tcr,la, .n. ‘l l; , arc ti:( h of thc 1″,ats that to ltc rc: ,;. , I; ., l: rel!;n. tani., , ./olio, IJuteilu, . 1!’i./_ ;lr”n. Iiam! Jr.r. F’l,nr_.Z.._%i;;, ,, : rt-Irn: am/ tf.rri.:, t?m steamer as a tr nW r. Uu ,tin;t, c ac?1 1″,at firm/ a t;nn, accor.liu; to .t rn. ‘Cl.w r. wu ru lm:nui MistinW /y in u;th, -. ink ;:,k as to “what w ax 1111, :111(I vle:iR a of ;: (,am( into, mnr r-, tm if tlm wo r( uu.i n:’ of t?u : la?:Iv. \ ‘c : ol in thc , ucr:atic , , Tlau :; will h:aw tu-li.r \. ‘1’Im yap?tts Il ,,n an,/ I, ,rr:l. r, (,t tf,is r:ity, start witli it, with lu:rtic: ol \ 1- e:l.k.

但是如果用rechaptcha后

The New-York State yacht Squadron, on its annual cruise to Newport came into the harbor yesterday afternoon. The following are the names of the boats that came to anchor here: Jessie, gera loliv erelun Annie, Mannering, Julia, Bonita, Magic wut, Rambler, floumblie, Henrietta, Sea-Drift and Maria, with the steamer America as a tender. On anchoring each boat fired a gun, according to custom. The reports were heard distinctly in the city, causing considerable inquiry as to “what was up,” and quite a number of sanguine individuals came into our office to inquire if the guns were not annunciatory signals of the successful laying of the Atlantic Cable. We invariably replied in the negative. The squadron will leave to-day for Newport. The yachts Washington and buub r of this city, start with it, with parties of New Haven people.

对.rechaptcha .

那个验证码中 一般有两个单词或者更多 其中一个是已经知道的正确的单词

另外个随机出现的就是某个文章下影印下来的

然后当用户提交的正确单词达到一定程度的时候就标记为这个单词

当我们用这个验证码的时候也不知不觉为rechaptcha项目做了贡献.

神奇吧

更多的信息可以参考google的网站

 

Written by princehaku

2月 22nd, 2011 at 11:18 下午

Posted in technology

with 3 comments

3 Responses to '关于recaptcha验证码'

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  1. 太强了……

    熊猫

    24 2月 11 at 1:16 上午

  2. 常用的是orc

    是OCR(Optical character recognition)

    沈蚊

    17 1月 12 at 9:34 下午

  3. 哦..对对.. 感谢指正

    princehaku

    18 1月 12 at 12:19 上午

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