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672 Chapter 20: Managing Scenes and Projects
only reads the 16-bit “half floating point RGBA
files that are considered standard EXR files.
Configuration File Usage
Most bitm ap I/O plug-ins, including those
integrated into 3ds Max, store their configuration
informationinabinaryCFGfilethatcannot
be edited. To allow external scripting support
as well as ordinary preferences, the OpenEXR
software uses a standard INI file for mat to store its
configuration data. The file is named
openexr .ini
and is found in the
plugcfg
folder in the program
directory. The file is generated aut o matically the
first time you edit the OpenEXR configuration
settings, and is updated each time you modify an
EXR loader. It is a standard text file and can be
modified with any text editor.
When the INI file is written, it automatically
generates a companion “help text file named
openexr_ini_help.txt
. This file contains the valid
ranges for var ious INI settings, as well as the
various text strings used to specify compression
type and bit depth. This file is just a guide; editing
it has no effect, and it is overwritten whenever the
INI file is updated.
To restore t he default settings after edit ing the INI
file, simply delete the
openexr .ini
file and a new
one with the original defaults will be generated the
next time you edit the configuration settings.
See also
Sav ing OpenEXR Files (page 3–672)
Opening OpenEXR Files (page 3–675)
S av i ng O penE XR Fil es
Render Scene dialog > Common panel > Common
Parameters rollout > Render Outp ut group > Click Files.
> Enter file name and set type to OpenEXR Image File >
Click Save. > Ope nEXR Configuration dialog
Rendered Frame Window > Click Save Bitm ap. > Enter file
name and set type to OpenEXR Image File > Click Save. >
OpenEXR Configuration dialog
Use the OpenEXR Configuration dialog dialog to
set output parameters for OpenEXR files. You can
specify the format for saving the RGBA data as
well as which of the four standard channels should
be saved. An option is available to use RealPixel
unclamped color information for Render Output
saving . Also available are color transforms to be
applied, file compression type, and additional
attributes.
Interfa ce
Co mpression TypeLets you choose the method
of file compression. The OpenEXR API
provides for three general types of lossless
compression, including two different methods of
Zip compression. For most images without a lot of
grain, the two Zip compression methods seem to
work best, w hi le the PIZ compression algorithm
is better suited to grainy images. The following
options are available:
None—Disables all compression.
RunLengthEncoding(RLE)Abasicform
of compression comparable to that used by
standard Targa files.