My friend Andrew and I implemented Stoke Width Transform (SWT) on a mobile phone during a class project at Cornell. Maybe you can get hint from the report.
The report: http://www.cs.cornell.edu/courses/cs4670/2010fa/projects/final/results/group_of_arp86_sk2357/Writeup.pdf
Our code: https://sites.google.com/site/roboticssaurav/strokewidthnokia
Updated code: https://github.com/aperrau/DetectText