The mobile phone as a platform for assisting the independent living ...

the two strings is calculated with an off-the-shelve algorithm based on the Levenshteindistance.We observed that a major factor of low performance was that a photograph of amedication box contains much more text information except from the name of themedication (Fig. 15). To overcome this obstacle, we tried to isolate only the words withthe maximum font size, which usually is the exact name of the medication.Fig. 16: Text information on a photograph of a medication box7.5 EvaluationIn order to evaluate this application, we intentionally have chosen to capturephotographs during different hours of the day, which lead to a variety of lightingconditions, as it would have happened with the use of this system in real timeenvironment. Also intentionally, we have chosen medication boxes with similar marketnames (e.g. Tenormin - Tonotil), as this could be a possible situation in a person’smedication list.We captured with the mobile phone’s camera 150 photographs of medication boxes. Inthe next step, we applied the image processing techniques mentioned in the previoussection to each photograph. For the needs of the evaluation process, we modified theapplication to be able to scan the contents of a folder and write the output (OCR resultsor medication name matching) to a Microsoft Office Word document.At the first stage of this experiment we performed OCR on the photographs and printedthe output of the OCR engine to the Word document. We consider that the applicationidentifies correctly the name of the medication if the output string contains the exactmarket name. At the second and third stage, we took advantage of the XML medication45