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Just open the pictures on your computer, there should be some way of resizing the picture. Off hand guess I would use about 450x450 pixels, seems to be a good size for posting on the web. Then save the picture to the harddrive as a ".jpeg" picture. This will compress it further and still look good. After that you should have no problems. Most picture viewer programs are able to resize pictures, even paint which comes with all windows operating systems.