please refer the following link
http://sharepointt.blogspot.com/2009/06/uploading-images-into-picture-library.html
Uploading images into picture library in sharepoint using c#
June 22, 2009
2 Comments | 
asp.net | Tagged: asp.net, c#, picture library, uploading images, wss3.0.sharepoint | 
Permalink
Posted by Ramesh Goud
