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Opening OpenEXR Files 675
Version OpenExr
The plug-in version, OpenEXR
API version, and ZLib version in plain text form.
Version 3dsMax The release version of 3ds Max
itself, t he API number, and the SDK revision used
when the build of 3ds Max was compiled. This
also reports whether the file was gener ated using
3ds Max or Autodesk VIZ.
Extended Channels
Z-Buf fer The standard buffer depth channel.
(16-bit or 32-bit flo ating point)
Object ID—The object ID f rom the
Object
Proper ties dialog (p age 1–112)
. (32-bit unsigned
integer)
Mater ial ID—The
material effects channel number
(page 2–1287)
. (32-bit unsigned integer)
Node R ender I D—A unique object ID set by the
renderer. All objects in the scen e have a un ique
Render ID, though the value stored varies from
renderer to renderer. (32-bit unsigned integer)
UV Coords—The UV coordinates for the object.
Only one UV channel is stored. (two slices, 16-bit
or 32-bit floating point)
Velocity—The 2D velocity vec tor for the pixel in
screen space. (two slices, 16-bit or 32-bit floating
point)
Normal—Thesurfacenormal.(threeslices,16-bit
or 32-bit floating point)
CoverageThe pixel coverage of the foremost
object in the pixel. (32-bit unsigned integer, 16-bit
floating point, or 32-bit floating point)
Opening OpenEXR Files
Any command that opens an image file, such as View
ImageFile>SpecifyanEXRfile.>ClickOpen.>OpenEXR
Configuration dialog
This version of the Ope nEXR Configuration dialog
appears w henever you open an EXR file. It lets
you specify various color transformations to be
applied to the loaded image, designate the internal
storage format to use, and preview the loaded
image with the color transforms applied. There
is also a histogram for viewing the brightness
distributionintheimageandadjustingthewhite
and black points interactively.
Interfa ce
Histogram
To view the h istogram, click the Preview button.
The histogram displays a detailed bar g r aph of the
distribution of brightness throughout the image.
The horizontal axis of the histogram defines the
luminance value, and the vertical axis indicates the