?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.relation=http%3A%2F%2Fmiis.maths.ox.ac.uk%2Fmiis%2F146%2F&rft.title=Backward+Diffusion+Methods+for+Digital+Halftoning&rft.creator=Gratton%2C+M.&rft.subject=Information+and+communication+technology&rft.description=We+examine+using+discrete+backward+diffusion+to+produce+digital+halftones.%0AThe+noise+introduced+by+the+discrete+approximation+to+backwards+diffusion+forces%0Athe+intensity+away+from+uniform+values%2C+so+that+rounding+each+pixel+to+black+or%0Awhite+can+produce+a+pleasing+halftone.+We+formulate+our+method+by+considering%0Athe+Human+Visual+System+norm+and+approximating+the+inverse+of+the+blurring%0Aoperator.+We+also+investigate+several+possible+mobility+functions+for+use+in+a%0Anonlinear+backward+diffusion+equation+for+higher+quality+results.&rft.date=2006-06-16&rft.type=Study+Group+Report&rft.type=NonPeerReviewed&rft.format=application%2Fpdf&rft.language=en&rft.identifier=http%3A%2F%2Fmiis.maths.ox.ac.uk%2Fmiis%2F146%2F1%2FIBM06.pdf&rft.identifier=++Gratton%2C+M.++(2006)+Backward+Diffusion+Methods+for+Digital+Halftoning.++%5BStudy+Group+Report%5D+++++