The Photo CD system provides an inexpensive means of participating in the information age with personal digital images. At the heart of the system is a 35 mm, 2000 pixels/inch scanner to acquire image data from a variety of photographic media. The raw data is then processed into a calibrated color metric, decomposed into a hierarchy of 5 resolution, compressed, encoded, and written to a compact disc using a high-speed CD writer. These discs can then be quickly displayed to a consumer television with a low-cost Photo CD player, that is also a high-quality CD-audio player. Additionally, Photo CD discs can be read into a computer using a CD-ROM XA drive, and manipulated on the desktop for importing into documents, or, for hard-copy printing to a variety of devices. The 35 mm-based system described above is only a part of a more generalized architecture. An add-on component capable of scanning larger format negatives and slides will soon be available, and will utilize extensions to the Photo CD format appropriate for these new image modalities. In particular, the formation of a 6th resolution and its relationship to the existing hierarchy will be discussed. Additionally, the structure of future extensions currently under development will be outlined in the context of the specific applications which they are designed to support.