TABLE OF CONTENTS Dave Bancroft
DPX Digital Picture Exchange is a file format designed to transport moving image representations on a file-per-still-frame basis. It comes with a rich supply of information fields built-in, organized into multiple, functionally-separated headers. This structure allows a wide variety of different image representations, both film- and video-derived, to be carried, while providing adequate support for rapid and efficient reading and processing of a received file. However, there are some caveats.
In the IT era today, we tend to use a strongly-disciplined approach in the classification of processes used in transferring data, for example the OSI stack, [1] and the reader will find strong evidence of this in other chapters of this book.
The origins of DPX, however, predate this era and have subjugated that discipline to the goal, in DPX, of being a very practical, application-oriented method of image coding and transfer for the moving image production industry. As such, it has a vertical approach in OSI terms embodying not only a file format and associated internal data referencing structure, but also specifying a large number of predefined payload types, offering optional data compression, and providing an internal indexing method for them. One or two of these types in particular, used in the electronic representation of motion-picture film originated images, represent the overwhelming majority of payloads carried in DPX, despite its equal ability to carry all the others that it allows, as well as offering virtually unlimited scope for...
