| Digital Picture Exchange | |
|---|---|
| Filename extension | .dpx |
| Internet media type | image/dpx |
| Developed by | SMPTE |
| Initial release | 1.0 / 18 February 1994; 32 years ago (1994-02-18) |
| Latest release | 2.0HDR 2018; 8 years ago (2018) |
| Type of format | Image file formats |
| Extended from | Cineon |
| Standard | ST 268-1:2014,[1] ST 268-2:2018[2] |
| Open format? | non-freeSMPTE standard, USD 175 |
| Website | www |
Digital Picture Exchange (DPX) is a commonfile format fordigital intermediate andvisual effects work and is aSMPTE standard (ST 268-1:2014). The file format is most commonly used to represent thedensity of each colour channel of a scanned negative film in an uncompressed "logarithmic" image where thegamma of theoriginal camera negative is preserved as taken by afilm scanner. For this reason, DPX is the worldwide-chosen format for still frames storage in most digital intermediate post-production facilities and film labs. Other common video formats are supported as well (see below), from video to purely digital ones, making DPX a file format suitable for almost any raster digital imaging applications. DPX provides, in fact, a great deal of flexibility in storing colour information, colour spaces and colour planes for exchange between production facilities. Multiple forms of packing and alignment are possible. The DPX specification allows for a wide variety of metadata to further clarify information stored (and storable) within each file.
The DPX file format was originally derived from theKodakCineon open file format (.cin file extension) used for digital images generated by Kodak's originalfilm scanner. The original DPX (version 1.0) specifications are part of SMPTE 268M-1994.[3] The specification was later improved and published bySMPTE asANSI/SMPTE 268M-2003. Academy Density Exchange (ADX) support for theAcademy Color Encoding System are added in the current version of the standard SMPTE ST 268-1:2014. Extensions forhigh-dynamic-range video andwide color gamut are standardized in SMPTE ST 268-2:2018.
SMPTE specifications dictate a mild number of compulsory metadata, like image resolution,color space details (channel depth, colorimetric metric, etc.), number of planes/subimages, as well as original filename and creation date/time, creator's name, project name,copyright information, and so on.
Furthermore, a couple of industry-specific metadata areas are present: Motion-Picture and Television ones. They are either used only if the picture has enough embedded information relevant to that specific industry, otherwise are left "empty". For example, Motion-Picture-specific metadata includes perforation-exactfilmKeyKode (if the image comes from a film scan), camera shutter angle, slate information and frame positioning within a frame sequence. On the other side, Television metadata includes fullSMPTE time code, video overscan and field information, and signal/colour level information.
A third, variable-size metadata area, which is user-definable, exists. Third-party applications/software occasionally use this area to store additional information; for example, when the DPX stores images with technical specifications far away from the original standard (like pictures coded in theCIEXYZ color space, orBayer-patterned raw frames from specific digital cameras like theArriflex D-21).
SMPTE ST 268-2:2018 defines a standards-based metadata section that supportsExtensible Metadata Platform,XML, andKLV metadata representations.
XnView can readFFmpegpix_fmt=abgr DPX images.ImageMagick supports DPX.[4] The C++ source of a DPX library is available.[5] DjV,[6] and vooya[7] support DPX sequences.IrfanView also has support for DPX images through a plugin.[8]Lasergraphics motion picture film scanning systems include support for output to DPX color/B&W 10/16-bit (conforms to SMPTE 268M for compatibility with graphics, compositing, and other post production systems).
| Raster | |
|---|---|
| Raw | |
| Vector | |
| Compound | |
| Metadata |
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