Automatic ASCII Art conversion of binary images using non-negative constraints

@inproceedings{OGrady2008AutomaticAA,
  title={Automatic ASCII Art conversion of binary images using non-negative constraints},
  author={P.D. O'Grady and Scott T. Rickard},
  year={2008}
}
It is hard to avoid ASCII Art in today's digital world, from the ubiquitous emoticons-;)-to the esoteric artistic creations that reside in many people's e-mail signatures, everybody has come across ASCII art at some stage. The origins of ASCII art can be traced back to the days when computers had a high price, slow operating speeds and low graphics capabilities, which forced computer programmers and enthusiasts to develop some innovative ways to render images using the limited graphics blocks… 

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