export & import blob between sqlite3, xml and iPhone

Question

I have problems with download and upload blob data in my iPhone app using Sqlite. Everything seems to be ok if I insert the photos in the blob field with SQLite manager: I can read the image and manage it with my app.

When I export the table to xml with the SQLite manager's feature, it creates a file that contains in the photo field a value like X'FFD8FFE000104A46....01010000010001000'.

After that I catch that value in a string with the method:

- (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string {

    str = [str stringByAppendingString:string];
 }

How can I get the image back from that string?

Thanks in advance

Andrea