From: stef <s@ctrlc.hu>
   On Wed, May 14, 2014 at 09:03:50AM -0700, jim bell wrote:
   > I guess I'm still not being clear.  It would be my way of objecting
   to a court's ordering the telecom company that
   >I might work for (or, one day, that I might own?!?) to present an
   "electronically-readable" form of the telephone >metadata of millions
   of telephones.  The judge ordered that; my sneaky response would be to
   generate an >"electronically-readable" file, basically a pdf file or a
   series of same, itself with an image that looks like >"captcha"
   information:  relatively easy for a human to read, but rather difficult
   for any computer to turn into >easily-useable (searchable) information.
    In other words, the information would be presented to the NSA, but it
   >would be essentially unuseable without being (first) human-decoded.
   >assuming this is correct:
   >[1]http://googleonlinesecurity.blogspot.de/2014/04/street-view-and-rec
   aptcha-technology.html
   >then googlestreetview tech is better at solving captchas than humans.
   For a single, tiny piece of "captcha", that might very well be true.
   But suppose the telephone metadata information for a billion phone
   calls per day is turned into "captcha's".  How much CPU power would the
   NSA have to apply, each day, just to back-convert that metadata into
   computer-searchable form?  Admittedly, that's irrelevant:  The NSA
   would simply ask the court to order the company to stop being a
   wiseass, and to stop using the captcha technique.
           Jim Bell

References

   1. http://googleonlinesecurity.blogspot.de/2014/04/street-view-and-recaptcha-technology.html