iPhone上的图像文件路径

I'm interested in uploading a file (image) from an iPhone library/camera roll to a remote web server. I already have a script working that will upload any file from the phone to a web server. However, I assume that to upload an image from the iPhone, I need the PATH to said image. Is there any way this can be done, once the user picks said image from the camera roll? I.e., how do I get the file path of an image selected in the camera roll?I'm interested in uploading a file (image) from