[Geocoding] Reverse-geocoding with large dataset

[jiangtao]

Hi all,
I'm doing a project which need conducting reverse-geocoding on 1.5 million GPS data points to get corresponding road type classification information. While, the Nominatim or other API service has a limit per day, and most of them charge a fair amount of money for such big dataset. 
I'm wondering if there is any way to finish this for free? I want do this myself, due to budget constraint as well as grab the chance to practice and put the process into the final report. 
Any help would be appreciated greatly! 
Tao  		 	   		  
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/geocoding/attachments/20160321/12185730/attachment.html>