Funny I was actually thinking about doing something like this the other day. I will write down what I think is a strategy to do 'intelligent' character recognition. I am quite confident that this technique is able to recognise printed characters in the noisy-ish images generated by sites like PayPal.

Core Component
Multi-layer, back propagating neural network. I will probably use the AI::NeuralNet::BackProp module to do this. The neural-net is then pre-trained with the fonts to be recognised.

Image Processing
You will definitely need to clean up the image somehow before feeding into the character recognition engine. The pre-processing would involve:
  • color image -> black/white convertion (to simplify the recognition)
  • noise reduction, including lines that run across the image
  • a pixel density count, statistics collection, determine text/character boundary

    Character Recognition Process
  • Input is an array of character bitmaps captured by the pre-processing steps
  • Feed the bitmap into the neural network, and get the best estimate of the character it contains
  • Output the characters recognised

    In reply to Re: Image Character Recognition by Roger
    in thread Image Character Recognition by booter2

    Title:
    Use:  <p> text here (a paragraph) </p>
    and:  <code> code here </code>
    to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.