AcademySoftwareFoundation/OpenImageIO Release-2.1.18.0 on GitHub

Release 2.1.18 (1 Aug 2020) -- compared to 2.1.17

Python ImageBuf.write() added a variety that takes an open ImageOutput.
This is the key to writing multi-subimage files from Python. #2640
oiiotool --eraseattrib fixed: was not applying to all subimages. #2632
RAW: Improve thread safety when more than one thread might be opening
different raw files at the same time. #2633
unordered_map_concurrent fixed a missing size decrement upon erase(). #2624
Fixes to support certain recent pybind11 changes. #2637
Fixes to support OpenColorIO v2. #2636
Fixes to support more recent fmtlib versions. #2639
PNG: document the "png:compressionLevel" output hint. #2642
In oiioversion.h, add a OIIO_MAKE_VERSION macro that constructs the
integer code for a particular major/minor/patch release. #2641