PD4 - Windows Live Photo Gallery Information File is one of the best file extensions that you could ever download. It is specially made for Windows Live Photo Gallery. If you are using this program, you will be able to take advantage of this extension. It will allow all users to handle home pictures and even movies. This extension also consists of metadata personal images and videos. It will let you know the file name and even the properties. There is also a specific name that the PD4 files use if you want to find out where your files are stored. It will usually be under Pictures.pd4.