From image size to pose and backdrop, U.S. passport photos need to meet very specific requirements to be accepted. Incorrectly formatted photos can result in processing delays, which can be a hassle if you need your passport for an upcoming trip. You can take your own passport photos at home or go to an official service provider, like a U.S. post office. With routine processing times ranging from four to six weeks, getting a new passport is a time-consuming operation—one that no one wants to prolong by providing the wrong type of passport photo. Along with keeping your eyes open and mouth closed, there are a few other specific rules and parameters to keep in mind. Here's everything you need to know about photo requirements for your U.S. passport book or card, including what to wear (and what not to wear), the correct image size, and approved backgrounds. Size and Resolution Getting the dimensions right is arguably the hardest part of providing your own passport photo. What is a passport-size photo? The U.S.…