HD Photo (formerly Windows Media Photo) is a still-image compression algorithm and file format for continuous tone photographic images, developed by Microsoft as a part of the Windows Media family. It supports lossy as well as lossless compression, and is the preferred image format for Microsoft's XPS documents. It was previously known internally as Photon. Software support for the format is not widespread as of early 2007; however, official managed code and unmanaged code implementations of the codec are available as part of .NET Framework 3.0 and Windows Imaging Component respectively. Both components are part of Windows Vista and are available for Windows XP.
HD Photo has been announced by Microsoft and the Joint Photographic Experts Group to be under consideration for a JPEG standard, tentatively titled JPEG XR.