OpenImageIO
-
OpenImageIO Release 2.0.3 (first stable 2.0 release)
Published by lgritz almost 6 years ago
Release 2.0 (Dec 7, 2018) -- compared to 1.8.x
New minimum dependencies:
- On Windows compiling with MSVS, the new minimum version is MSVS 2015.
Major new features and improvements:
- ImageInput and ImageOutput static create() and open() methods now return
unique_ptr
rather than raw pointers. #1934, #1945 (1.9.3).
- ImageInput improvements to thread safety and concurrency, including some
new API calls (see "Public API changes" section below).
- ImageBufAlgo overhaul (both C++ and Python): Add IBA functions that
return image results directly rather than passing ImageBuf references
as parameters for output (the old kind of calls still exist, too, and
have their uses). Also in C++, change all IBA functions that took raw
pointers to per-channel colors into span<>
for safety. #1961 (1.9.4)
- For some readers and writers, an "IOProxy" can be passed that customizes
the I/O methods. An important use of this is to write an image "file"
to memory or to read an image "file" from a memory, rather than disk.
Currently, OpenEXR supports this for both reading and writing, and PNG
supports it for writing. You specify a pointer to the proxy via the
configuration option "oiio:ioproxy". #1931 (1.9.3)
- New Image Format support:
- OpenVDB file read (as volume images or accessing via texture3d()).
#2010,2018 (1.9.4)
- "null" images -- null reader just returns black (or constant colored)
pixels, null writer just returns. This can be used for benchmarking
(to eliminate all actual file I/O time), "dry run" where you want to
test without creating output files. #1778 (1.9.0), #2042 (1.9.4)
- TIFF I/O of multiple scanlines or tiles at once (or whole images, as is
typical use case for oiiotool and maketx) is sped up by a large factor
on modern multicore systems. We've seen 10x or more faster oiiotool
performance for uint8 and uint16 TIFF files using "zip" (deflate)
compression, on modern 12-16 core machines. #1853 (1.9.2)
- Major refactor of Exif metadata handling, including much more complete
metadata support for RAW formats and support of camera "maker notes"
for Canon cameras. #1774 (1.9.0)
- New
maketx
option --bumpslopes
specifically for converting bump maps,
saves additional channels containing slope distribution moments that can
be used in shaders for "bump to roughness" calculations. #1810,#1913,2005
(1.9.2), #2044 (1.9.4)
- An official FindOpenImageIO.cmake that we invite you to use in other
cmake-based projects that needs to find OIIO. #2027 (1.9.4)
Public API changes:
Performance improvements:
- ImageBufAlgo::computePixelStats is now multithreaded and should improve by
a large factor when running on a machine with many cores. This is
particularly noticable for maketx. #1852 (1.9.2)
- Color conversions are sped up by 50% for 4 channel float images, about
30% for other combinations of channels or data formats. #1868 (1.9.2)
- ImageBuf::get_pixels() sped up by around 3x for the common case of the
image being fully in memory (the slower path is now only used for
ImageCache-based images). #1872 (1.9.2)
- ImageBufAlgo::copy() and crop() sped up for in-memory buffers, by about
35-45% when copying between buffers of the same type, 2-4x when copying
between buffers of different data types. #1877 (1.9.2)
- ImageBufAlgo::over() when both buffers are in-memory, float, 4-channels,
sped up by about 2x. #1879 (1.9.2).
- ImageBufAlgo::fill() of a constant color sped up by 1.5-2.5x (depending
on the data type involved). #1886 (1.9.2)
Fixes and feature enhancements:
- oiiotool
-
--help
prints important usage tips that explain command parsing,
syntax of optional modifiers, and the path to PDF docs. #1811 (1.9.2)
-
--colormap
has new maps "inferno", "magma", "plasma", "viridis",
which are perceptually uniform, monotonically increasing luminance,
look good converted to greyscale, and usable by people with color
blindness. #1820 (1.9.2)
- oiiotool no longer enables autotile by default. #1856 (1.9.2)
-
--colorconvert
, --tocolorspace
, and all of the --ocio
commands
now take an optional modifier :unpremult=1
which causes the color
conversion to be internally bracketed by unpremult/premult steps (if
the image has alpha and is not already marked as having unassociated
alpha). You should therefore prefer --colorconvert:unpremult=1 from to
rather than the more complex --unpremult --colorconvert from to -premult
.
#1864 (1.9.2)
-
--autocc
will also cause unpremult/premult to bracket any color
transformations it does automatically for read and write (if the image
has alpha and does not appear to already be unassociated). #1864 (1.9.2)
-
--help
prints the name of the OCIO color config file. #1869 (1.9.2)
- Frame sequence wildcard improvements: fix handling of negative frame
numbers and ranges, also the --frames
command line option is not
enough to trigger a loop over those frame numbers, even if no other
arguments appear to have wildcard structure. #1894 (1.8.10/1.9.2)
-
--info -v
now prints metadata in sorted order, making it easier to
spot the existance of particular metadata. #1982 (1.9.4)
-
--no-autopremult
fixed, it wasn't working properly for cases that
were read directly rather than backed by ImageCache. #1984 (1.9.4)
- New
--contrast
allows for contrast remapping (linear or sigmoidal).
#2043 (1.9.4)
- Improved logic for propagating the pixel data format through
multiple operations, especially for files with multiple subimages.
#1769 (1.9.0/1.8.6)
- Outputs are now written to temporary files, then atomically moved
to the specified filename at the end. This makes it safe for oiiotool
to "overwrite" a file (i.e. oiiotool in.tif ... -o out.tif
) without
problematic situations where the file is truncated or overwritten
before the reading is complete. #1797 (1.8.7/1.9.1)
- Fixed problem with reading
half
files where very small (denormalized)
half values could get squashed to float 0.0 instead of having their
values preserved, if certain old versions of libopenjpeg were being
used (because they set a CPU flag strangely upon library load and then
never changed it back, this is a libopenjpeg bug that has since been
fixed). #2048 (2.0)
-
-d chan=type
logic fixed for certain cases of specifying the data
types of individual channels. #2061 (2.0beta2)
- Expression evaluation: metadata names can now be enclosed in single
or double quotes if they don't follow "C" identifier naming conventions.
For example, {TOP.'foo/bar'}
retrieves metadata called "foo/bar"
rather than trying to retrieve "foo" and divide by bar. #2068 (2.0beta2)
- Expression evaluation: When retrieving metadata, timecode data will be
expressed properly as a string ("00:00:00:00"). #2068 (2.0beta2)
- ImageBufAlgo:
-
color_map()
supports new maps "inferno", "magma", "plasma",
"viridis". #1820 (1.9.2)
- Across many functions, improve channel logic when combining an image
with alpha with another image without alpha. #1827 (1.9.2)
-
mad()
now takes an img*color+img
variety. (Previously it
supported img*img+img
and img*color+color
.) #1866 (1.9.2)
- New
fit()
is like resize but fits inside a specified window size,
while preserving the aspect ratio of the image appearance. #1993.
- New
contrast_remap()
allows flexible linear or sigmoidal contrast
remapping. #2043 (1.9.4)
-
channel_append()
is no longer limited to requiring the two input
images to have the same pixel data type. #2022 (1.9.4)
-
isConstantColor()
, isConstantChannel()
, and isMonochrome()
have
added an optional threshold
parameter that allows you to compute
whether the image is constant or monochrome within a non-zero
tolerance (the default is still 0.0, meaning checking for an exact
match). #2049 (2.0.0)
-
IBA::ociodisplay()
has better behavior when its "fromspace" parameter
is left blank -- instead of assuming "linear" (as a space name), it
assumes it's whatever space in your OCIO color config has the "linear"
role. #2083 (1.8.17/2.0.1)
- ImageBuf:
- Bug fixed in IB::copy() of rare types. #1829 (1.9.2)
- write() automatically tells the ImageCache to 'invalidate' the file
being written, so cached images will not retain the prior version of
the files. #1916 (1.9.2)
- Bug fix to ImageBuf::contains_roi() method -- it erroneously always
returned true
. #1997 (1.8.14/1.9.4)
- ImageCache/TextureSystem/maketx:
- Improved stats on how long we wait for ImageInput mutexes.
#1779 (1.9.0/1.8.6)
- Improved performance of IC/TS tile and file caches under heavy
contention from many threads. #1780 (1.9.0)
- Increased the default
max_tile_channels
limit from 5 to 6.
#1803 (1.9.1)
- maketx: improved image hashing to avoid some (extremely rare) possible
hash collisions. #1819 (1.9.2)
- IC/TS performance improvements by changing the underlying hash table
implementation. #1823,1824,1825,1826,1830 (1.9.2)
- texture()/texture3d(): when requesting a nonexistant "subimage",
return the fill color, like we do when requesting nonexistant channels
(rather than nondeterministically simply not filling in the result).
#1917 (1.9.2)
- Relying on some changes to the ImageInput API, there is now much less
thread locking to protect the underlying ImageInputs, and this should
improve texture and image cache performance when many threads need
to read tiles from the same file. #1927 (1.9.2)
-
get_image_info()
/get_texture_info()
is now more flexible about
retrieving arrays vs aggregates, in cases where the total number of
elements is correct. #1968 (1.9.4)
- Fix uninitialized read within the texture system (only affected
statistics, never gave wrong texture results). #2000 (1.9.4)
- texture3d() transforms lookup points from world into local space
if the file has a "worldtolocal" metadata giving a 4x4 matrix. #2009
(1.9.4)
- Fix minor texture filtering bug where widely disparate "sblur" and
"tblur" values could in some circumstances lead to incorrect texture
filter estimation. #2052 (2.0.0)
-
ImageCache::invalidate(filename)
did not properly invalidate the
"fingerprint" is used to detect duplicate files. #2081 (1.8.17/2.0.1)
- iv:
- Fix (especially on OSX) for various ways it has been broken since the
shift to Qt5. #1946 (1.8.12, 1.9.4)
- New optin
--no-autopremult
works like oiiotool, causes images with
unassociated alpha to not be automatically premultiplied by alpha
as they are read in. #1984 (1.9.4)
- All string->numeric parsing and numeric->string formatting is now
locale-independent and always uses '.' as decimal marker. #1796 (1.9.0)
- Python Imagebuf.get_pixels and set_pixels bugs fixed, in the varieties
that take an ROI to describe the region. #1802 (1.9.2)
- Python: Implement missing
ImageOutput.open()
call variety for declaring
multiple subimages. #2074 (2.0.1)
- More robust parsing of XMP metadata for unknown metadata names.
#1816 (1.9.2/1.8.7)
- Fix ImageSpec constructor from an ROI, display/"full" window did not get
the right default origin. #1997 (1.8.14/1.9.4)
- ImageSpec::erase_attribute() fix bug where it got case-sensitivity of the
search backwards when built using std::regex rather than boost::regex.
#2003 (1.8.14/1.9.4)
- DPX:
- Better catching of write errors, including filling the disk while in
the process of writing a DPX file. #2072 (2.0.1)
- Field3d:
- Prevent crashes when open fails. #1848 (1.9.2/1.8.8)
- Fix potential mutex deadlock. #1972 (1.9.4)
- GIF:
- Fix crash when reading GIF with comment extension but no comment data.
#2001 (1.8.14/1.9.4)
- JPEG:
- When writing, be robust to accidentally setting the "density" metadata
to values larger than JPEG's 16 bit integer field will accommodate.
#2002 (1.8.14/1.9.4)
- Better detection and reporting of error conditions while reading
corrupt JPEG files. #2073 (2.0.1)
- OpenEXR:
- Gracefully detect and reject files with subsampled channels,
which is a rarely-to-never-used OpenEXR feature that we don't support
properly. #1849 (1.9.2/1.8.8)
- Improved handling of UTF-8 filenames on Windows. #1941 (1.9.3, 1.8.12,
1.7.19)
- PNG:
- Fix redundant png_write_end call. #1910 (1.9.2)
- PSD:
- Fix parse issue of layer mask data. #1777 (1.9.2)
- RAW:
- Add "raw:HighlightMode" configuration hint to control libraw's
handling of highlight mode processing. #1851
- Important bug fix when dealing with rotated (and vertical) images,
which were not being re-oriented properly and could get strangely
scrambled. #1854 (1.9.2/1.8.9)
- Major rewrite of the way makernotes and camera-specific metadata are
handled, resulting in much more (and more accurate) reporting of
camera metadata. #1985 (1.9.4)
- The "oiio:ColorSpace" metadata is now set correctly when reading
raw DSLR images. And we deprecate the old "raw:ColorSpace" metadata,
which is useless. #2016 (1.9.4)
- Add "raw:aber" configuration hint to control libraw's adjustments for
chromatic aberration. This data is of type "float[2]", the first value
is the scale factor for red, the second for blue, and both should be
very close to 1.0. #2030 (1.9.4)
- TIFF:
- Improve performance of TIFF scanline output. #1833 (1.9.2)
- Bug fix: read_tile() and read_tiles() input of un-premultiplied tiles
botched the "shape" of the tile data array. #1907 (1.9.2/1.8.10)
- Improvement in speed of reading headers (by removing redundant call
to TIFFSetDirectory). #1922 (1.9.2)
- When config option "oiio:UnassociatedAlpha" is nonzero (or not set
-- which is the default), therefore enabling automatic premultiplication
by alpha for any unassociated alpha files, it will set the metadata
"tiff:UnassociatedAlpha" to indicate that the original file was
unassociated. #1984 (1.9.4)
- Bug fixes for TIFF reads of images with unassociated alpha -- there
were some edge cases where they pixels failed to automatically
premultiply upon read. #2032 (1.9.4)
- zfile: more careful gzopen on Windows that could crash when given bogus
filename. #1839,2070 (1.9.2/1.8.8/2.0.1)
- Windows fix: Safer thread pool destruction on. #2038 (1.9.4)
Build/test system improvements and platform ports:
- Fixes for Windows build. #1793, #1794 (1.9.0/1.8.6), #2025 (1.9.4)
- Fix build bug where if the makefile wrapper got
CODECOV=0
, it would
force a "Debug" build (required for code coverage tests) even though code
coverage is instructed to be off. (It would be fine if you didn't specify
CODECOV
at all.) #1792 (1.9.0/1.8.6)
- Build: Fix broken build when Freetype was not found or disabled. #1800
(1.8.6/1.9.1)
- Build: Boost.Python is no longer a dependency, but
pybind11
is. If
not found on the system, it will be automatically downloaded. #1801, #2031
(1.9.1)
- Time for a multi-core build of OIIO is reduced by 40% by refactoring some
extra big modules into more bite-sized pieces. #1806 (1.9.2)
- testtex:
- Make the "thread workout" cases all honor
--handle
. #1778 (1.9.0)
- Only prints detailed stats if
-v
is used, and new option
--invalidate
will invalidate the cache when starting each
threadtimes trial. #1828 (1.9.2)
- New
--anisoratio
lets you choose anisotropic shape for thread
working tests, and make thread_workout samples twice as big to be more
typical by interpolating mip levels. #1840 (1.9.2)
- TextureSystem stats are printed as well as ImageCache. #1840 (1.9.2)
- iv no longer requires GLEW, using QOpenGLFunctions instead. #1840 (1.9.2)
- DICOM: Fix dcmtk build errors on some platforms. Also, the minimum dcmtk
version we suport is 3.6.1. #1843 (1.9.2/1.8.8)
- Build fixes for Hurd OS. #1850 (1.9.2/1.8.8)
- Clean up leak sanitizer errors. #1855 (1.9.2)
- On Unix/Linux, add explicit DL library dependency to libOpenImageIO.so
itself instead of only to the binaries and test utilities.
#1860 (1.9.2/1.8.8)
- The build now bundles a sample OCIO config in testsuite/common so that we
can do OCIO-based unit tests. #1870 (1.9.2)
- Properly find newer openjpeg 2.3. #1871 (1.9.2)
- Fix testsuite to be Python 2/3 agnostic. #1891 (1.9.2)
- Removed
USE_PYTHON3
build flag, which didn't do anything. #1891 (1.9.2)
- The
PYTHON_VERSION
build variable is now better at selecting among
several installed versions of Python, and all the tests should work fine
with Python 3.x now. #2015 (1.9.4)
- Remove some lingering support for MSVS < 2013 (which we haven't advertised
as working anyway). #1887 (1.9.2)
- Windows/MSVC build fix: use the
/bigobj
option on some large modules
that need it. #1900, #1902 (1.8.10/1.9.2)
- Add up-to-date Nuke versions to FindNuke.cmake. #1920 (1.8.11, 1.9.2)
- Allow building against ffmpeg 4.0. #1926,#1936 (1.8.11, 1.9.2)
- Disable SSE for 32 bit Windows -- problematic build issues.
#1933 (1.9.3, 1.8.12, 1.7.19)
- Fixes to the
EMBEDPLUGINS=0
build case, which had at some point stopped
working properly. #1942 (1.9.3)
- Improvements in finding the location of OpenJPEG with Macports.
#1948 (1.8.12, 1.9.4)
- Improvement finding libraw properly on Windows. #1959 (1.9.4)
- Fix warnings to allow clean gcc8 builds. #1974 (1.9.4)
- Make sure we build properly for C++17. (1.9.4)
- Check properly for minimal FFMpeg version (2.6). #1981 (1.9.4)
- New build option GLIBCXX_USE_CXX11_ABI, when set to 0 will force the old
gcc string ABI (even gcc 7+ where the new ABI is the default), and if set
to 1 will force the new gcc string ABI (on gcc 5-6, where old ABI is the
default). If not set at all, it will respect the default choice for that
compiler. #1980 (1.9.4)
- TravisCI builds now use an abbreviated test matrix for most ordinary
pushes of working branches, but the full test matrix for PRs or pushes
to "master" or "RB" branches. #1983 (1.9.4)
- Support compilation by clang 7.0. #1995 (1.9.4)
- Support for building against OpenEXR 2.3. #2007 (1.9.4)
- Use OpenEXR pkgconfig if available. #2008 (1.9.4)
- Allow builds outside the source tree to pass testsuite. Defaults to
finding test image directories such as oiio-images, openexr-images, and
libtiffpic in the usual ".." from the main OIIO source directory, but now
it can be overridden with the CMake variable OIIO_TESTSUITE_IMAGEDIR
.
#2026 (1.9.4)
- Remove stale python examples from
src/python
. They were untested,
undocumented, and probably no longer worked against the current APIs.
#2036 (1.9.4)
- Fixes for Windows when making Unicode builds, and fix Plugin::dlopen
on Windows to properly support UTF-8 filenames. #1454 (2.0.1)
- Support added for OpenCV 4.0. (2.0.1)
Developer goodies / internals:
-
Formatting with clang-format: All submissions are expected to be
formatted using our standard clang-format rules. Please run
make clang-format
prior to submitting code. The TravisCI tests include
one entry just to check that the formatting conforms, and will fail if it
doesn't, printing the diffs that would bring it to proper formatting.
(Note: for small changes, if you don't have clang-format locally, it's ok
to submit, then use the diffs from the failures to fix it by hand and
resubmit and update.) #2059,2064,2065,2067,2069.
- argparse.h:
- Add pre- and post-option help printing callbacks. #1811 (1.9.2)
- Changed to PIMPL to hide implementation from the public headers.
Also modernized internals, no raw new/delete. #1858 (1.9.2)
- array_view.h:
- Added begin(), end(), cbegin(), cend() methods, and new
constructors from pointer pairs and from std::array. (1.9.0/1.8.6)
- Deprecated, moved contents to span.h. You should change
array_view<T>
to span<T>
and array_view<const T>
to cspan<T>
. #1956 (1.9.4)
- color.h: add guards to make this header safe for Cuda compilation.
#1905 (1.9.2/1.8.10)
- filesystem.h:
- IOProxy classes that can abstract file operations for custom I/O
substitutions. #1931 (1.9.3)
- Proper UTF-8 filenames for unique_path() and temp_directory(), and
general UTF-8 cleanup/simplification. #1940 (1.9.3, 1.8.12, 1.7.19)
- fmath.h:
- Now defines preprocessor symbol
OIIO_FMATH_H
so other files can
easily detect if it has been included. (1.9.0/1.8.6)
- Modify to allow Cuda compilation/use of this header. #1888,#1896
(1.9.2/1.8.10)
- Improve numeric approximation of fast_atan() and fast_atan2().
#1943 (1.9.3)
- fast_cbrt() is a fast approximate cube root (maximum error 8e-14,
about 3 times faster than pow computes cube roots). #1955 (1.9.4)
- function_view.h: Overhauled fixed with an alternate implementation
borrowed from LLVM. (1.9.4)
- hash.h: add guards to make this header safe for Cuda compilation.
#1905 (1.9.2/1.8.10)
- imageio.h:
convert_image()
and parallel_convert_image
have been
simplified to remove optional alpha_channel
and z_channel
parameters
that were never actually used. The old versions are still present but
are deprecated. #2088 (2.0.1)
- parallel.h:
-
parallel_options
passed to many functions. #1807 (1.9.2)
- More careful avoidance of threads not recursively using the thread
pool (which could lead to deadlocks). #1807 (1.9.2)
- Internals refactor of task_set #1883 (1.9.2).
- Make the thread pool better behaved in times if pool congestion -- if
there are already way too many items in the task queue, the caller may
do the work itself rather than add to the end and have to wait too
long to get results. #1884 (1.9.2)
- paramlist.h:
- ParamValue class has added get_int_indexed() and get_float_indexed()
methods. #1773 (1.9.0/1.8.6)
- ParamValue restructured to allow additional common data types to store
internally rather than requre an allocation. #1812 (1.9.2)
- New ParamList convenience methods: remove(), constains(),
add_or_replace(). #1813 (1.9.2)
- platform.h:
- New OIIO_FALLTHROUGH and OIIO_NODISCARD macros, and renamed
OIIO_UNUSED_OK to OIIO_MAYBE_UNUSED (to match C++17 naming). #2041
- simd.h:
- Fixed build break when AVX512VL is enabled. #1781 (1.9.0/1.8.6)
- Minor fixes especially for avx512. #1846 (1.9.2/1.8.8) #1873,#1893
(1.9.2)
- span.h:
- Used to be array_view. Now it's
span<>
and span_strided
. Also,
cspan<T>
is a handy alias for span<const T>
. #1956 (1.9.4)
- Added begin(), end(), cbegin(), cend() methods, and new
constructors from pointer pairs and from std::array. (1.9.0/1.8.6)
- Added
==
and !=
to span and span_strided. #2037 (1.9.4)
- strutil.h:
- All string->numeric parsing and numeric->string formatting is now
locale-independent and always uses '.' as decimal marker. #1796 (1.9.0)
- New
Strutil::stof()
, stoi()
, stoui()
, stod()
functions for
easy parsing of strings to numbers. Also tests Strutil::string_is_int()
and string_is_float()
. #1796 (1.9.0)
- New
to_string<>
utility template. #1814 (1.9.2)
- Fix to strtof, strtod for non-C locales. #1918 (1.8.11, 1.9.2)
- New
iless()
is case-insensitive locale-independent string_view
ordering comparison. Also added StringIEqual, StringLess, StringILess
functors. (1.9.4)
-
join()
is now a template that can act on any iterable container of
objects that allow stream output. #2033 (1.9.4)
- New
splits()
/splitsv()
that direction returns a vector of
std::string or string_view, respectively. #2033 (1.9.4)
- A second version of
extract_from_list_string
that directly returns
a std::vector (instead of being passed as a param). #2033 (1.9.4)
-
parse_string
now accepts single quotes as well as double quotes
to enclose a quoted string. #2066 (2.0beta2)
- Fix Strutil::vsnprintf detection of encoding errors on Windows. #2082
(1.8.17/2.0.1)
- thread.h:
- Reimplementaiton of
spin_rw_mutex
has much better performance when
many threads are accessing at once, especially if most of them are
reader threads. #1787 (1.9.0)
- task_set: add wait_for_task() method that waits for just one task in
the set to finish (versus wait() that waits for all). #1847 (1.9.2)
- Fix rare crash in thread pool when lowering the number of threads.
#2013 (1.9.4/1.8.15)
- unittest.h:
- Made references to Strutil fully qualified in OIIO namespace, so that
unittest.h
can be more easily used outside of the OIIO codebase.
#1791 (1.9.0)
-
OIIO_CHECK_EQUAL_APPROX
- fix namespace ambiguity. #1998 (1.9.4)
-
OIIO_CHECK_EQUAL
now can compare two std::vector
s. #2033 (1.9.4)
- Make unit test errors respect whether stdout is a terminal when
deciding whether to print in color. #2045
- Extensive use of C++11
final
and override
decorators of virtual
methods in our internals, especially ImageInput and ImageOutput.
#1904 (1.9.2)
Notable documentation changes:
- A new LICENSE-THIRD-PARTY.md file reproduces the full open source licenses
of all code that we distribute with OIIO, incorporate, or derive code from.
They are have very similar license terms to the main OIIO license
("New BSD") -- MIT, Mozilla, Apache 2.0, or public domain. OIIO does not
use any GPL or other "viral" licenesed code that would change license
terms of any code that didn't come directly from those packages.
- The CHANGES.md file was getting truly enormous, so we have split the
release notes from the 0.x and 1.x releases into separate files found
in src/doc. So CHANGES.md only documents 2.0 and beyond.