I personally find it ridiculaor that people are
suggesting that something
 like a paper tape reader, for which the mechanical parts could be made in
 any model engineer's workshop and the electronics is a handful of parts
 should be emulated by a scanner (many moe photodetectors than necessary
 and a powerful processor to prewcess the images from said scanner. Please
 stop trhwing silicon ant the problem! 
    Tony, I have the means of building a paper reader, I believe you too.
But how many of this ist has the means? :oP
    This is something to think about. The HOW the job must be done sometimes
is less important than the job done by itself.