Installation problems

[SebastianGrans]

When I try to install OpenEXR via pip I get the error shown below.
Any recommendations on how to resolve this?

Edit: I forgot to mention:

• MacOS 10.14.6
• Python 3.7.7
• clang version 11.0.0 (clang-1100.0.33.17)
• zlib 1.2.11
• openexr 2.4.1

~ ❯❯❯ pip3 install openexr
Collecting openexr
  Using cached OpenEXR-1.3.2.tar.gz (10 kB)
Building wheels for collected packages: openexr
  Building wheel for openexr (setup.py) ... error
  ERROR: Command errored out with exit status 1:
   command: /usr/local/opt/python/bin/python3.7 -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/private/var/folders/xh/vt7q8pbj61xdnmm3b5s1nxph0000gn/T/pip-install-_nhnanva/openexr/setup.py'"'"'; __file__='"'"'/private/var/folders/xh/vt7q8pbj61xdnmm3b5s1nxph0000gn/T/pip-install-_nhnanva/openexr/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' bdist_wheel -d /private/var/folders/xh/vt7q8pbj61xdnmm3b5s1nxph0000gn/T/pip-wheel-6zbe5i9b
       cwd: /private/var/folders/xh/vt7q8pbj61xdnmm3b5s1nxph0000gn/T/pip-install-_nhnanva/openexr/
  Complete output (41 lines):
  running bdist_wheel
  running build
  running build_py
  creating build
  creating build/lib.macosx-10.14-x86_64-3.7
  copying Imath.py -> build/lib.macosx-10.14-x86_64-3.7
  running build_ext
  building 'OpenEXR' extension
  creating build/temp.macosx-10.14-x86_64-3.7
  clang -Wno-unused-result -Wsign-compare -Wunreachable-code -fno-common -dynamic -DNDEBUG -g -fwrapv -O3 -Wall -isysroot /Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk -I/Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk/usr/include -I/Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk/System/Library/Frameworks/Tk.framework/Versions/8.5/Headers -I/usr/include/OpenEXR -I/usr/local/include/OpenEXR -I/opt/local/include/OpenEXR -I/usr/local/include -I/usr/local/opt/openssl@1.1/include -I/usr/local/opt/sqlite/include -I/usr/local/Cellar/python/3.7.7/Frameworks/Python.framework/Versions/3.7/include/python3.7m -c OpenEXR.cpp -o build/temp.macosx-10.14-x86_64-3.7/OpenEXR.o -g -DVERSION="1.3.2"
  In file included from OpenEXR.cpp:40:
  In file included from /usr/local/include/OpenEXR/ImfAttribute.h:48:
  In file included from /usr/local/include/OpenEXR/ImfXdr.h:108:
  /usr/local/include/OpenEXR/half.h:99:15: warning: defaulted function definitions are a C++11 extension [-Wc++11-extensions]
      half () = default;                  // no initialization
                ^
  /usr/local/include/OpenEXR/half.h:102:16: warning: defaulted function definitions are a C++11 extension [-Wc++11-extensions]
      ~half () = default;
                 ^
  /usr/local/include/OpenEXR/half.h:103:27: warning: defaulted function definitions are a C++11 extension [-Wc++11-extensions]
      half (const half &) = default;
                            ^
  /usr/local/include/OpenEXR/half.h:104:16: warning: rvalue references are a C++11 extension [-Wc++11-extensions]
      half (half &&) noexcept = default;
                 ^
  /usr/local/include/OpenEXR/half.h:104:19: error: expected ';' at end of declaration list
      half (half &&) noexcept = default;
                    ^
                    ;
  /usr/local/include/OpenEXR/half.h:124:43: warning: defaulted function definitions are a C++11 extension [-Wc++11-extensions]
      half &              operator = (const half  &h) = default;
                                                        ^
  /usr/local/include/OpenEXR/half.h:125:31: warning: rvalue references are a C++11 extension [-Wc++11-extensions]
      half &              operator = (half  &&h) noexcept = default;
                                            ^
  /usr/local/include/OpenEXR/half.h:125:35: error: expected ';' at end of declaration list
      half &              operator = (half  &&h) noexcept = default;
                                                ^
                                                ;
  6 warnings and 2 errors generated.
  error: command 'clang' failed with exit status 1
  ----------------------------------------
  ERROR: Failed building wheel for openexr
  Running setup.py clean for openexr
Failed to build openexr
Installing collected packages: openexr
    Running setup.py install for openexr ... error
    ERROR: Command errored out with exit status 1:
     command: /usr/local/opt/python/bin/python3.7 -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/private/var/folders/xh/vt7q8pbj61xdnmm3b5s1nxph0000gn/T/pip-install-_nhnanva/openexr/setup.py'"'"'; __file__='"'"'/private/var/folders/xh/vt7q8pbj61xdnmm3b5s1nxph0000gn/T/pip-install-_nhnanva/openexr/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /private/var/folders/xh/vt7q8pbj61xdnmm3b5s1nxph0000gn/T/pip-record-7al_kvzq/install-record.txt --single-version-externally-managed --compile --install-headers /usr/local/include/python3.7m/openexr
         cwd: /private/var/folders/xh/vt7q8pbj61xdnmm3b5s1nxph0000gn/T/pip-install-_nhnanva/openexr/
    Complete output (41 lines):
    running install
    running build
    running build_py
    creating build
    creating build/lib.macosx-10.14-x86_64-3.7
    copying Imath.py -> build/lib.macosx-10.14-x86_64-3.7
    running build_ext
    building 'OpenEXR' extension
    creating build/temp.macosx-10.14-x86_64-3.7
    clang -Wno-unused-result -Wsign-compare -Wunreachable-code -fno-common -dynamic -DNDEBUG -g -fwrapv -O3 -Wall -isysroot /Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk -I/Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk/usr/include -I/Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk/System/Library/Frameworks/Tk.framework/Versions/8.5/Headers -I/usr/include/OpenEXR -I/usr/local/include/OpenEXR -I/opt/local/include/OpenEXR -I/usr/local/include -I/usr/local/opt/openssl@1.1/include -I/usr/local/opt/sqlite/include -I/usr/local/Cellar/python/3.7.7/Frameworks/Python.framework/Versions/3.7/include/python3.7m -c OpenEXR.cpp -o build/temp.macosx-10.14-x86_64-3.7/OpenEXR.o -g -DVERSION="1.3.2"
    In file included from OpenEXR.cpp:40:
    In file included from /usr/local/include/OpenEXR/ImfAttribute.h:48:
    In file included from /usr/local/include/OpenEXR/ImfXdr.h:108:
    /usr/local/include/OpenEXR/half.h:99:15: warning: defaulted function definitions are a C++11 extension [-Wc++11-extensions]
        half () = default;                  // no initialization
                  ^
    /usr/local/include/OpenEXR/half.h:102:16: warning: defaulted function definitions are a C++11 extension [-Wc++11-extensions]
        ~half () = default;
                   ^
    /usr/local/include/OpenEXR/half.h:103:27: warning: defaulted function definitions are a C++11 extension [-Wc++11-extensions]
        half (const half &) = default;
                              ^
    /usr/local/include/OpenEXR/half.h:104:16: warning: rvalue references are a C++11 extension [-Wc++11-extensions]
        half (half &&) noexcept = default;
                   ^
    /usr/local/include/OpenEXR/half.h:104:19: error: expected ';' at end of declaration list
        half (half &&) noexcept = default;
                      ^
                      ;
    /usr/local/include/OpenEXR/half.h:124:43: warning: defaulted function definitions are a C++11 extension [-Wc++11-extensions]
        half &              operator = (const half  &h) = default;
                                                          ^
    /usr/local/include/OpenEXR/half.h:125:31: warning: rvalue references are a C++11 extension [-Wc++11-extensions]
        half &              operator = (half  &&h) noexcept = default;
                                              ^
    /usr/local/include/OpenEXR/half.h:125:35: error: expected ';' at end of declaration list
        half &              operator = (half  &&h) noexcept = default;
                                                  ^
                                                  ;
    6 warnings and 2 errors generated.
    error: command 'clang' failed with exit status 1
    ----------------------------------------
ERROR: Command errored out with exit status 1: /usr/local/opt/python/bin/python3.7 -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/private/var/folders/xh/vt7q8pbj61xdnmm3b5s1nxph0000gn/T/pip-install-_nhnanva/openexr/setup.py'"'"'; __file__='"'"'/private/var/folders/xh/vt7q8pbj61xdnmm3b5s1nxph0000gn/T/pip-install-_nhnanva/openexr/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /private/var/folders/xh/vt7q8pbj61xdnmm3b5s1nxph0000gn/T/pip-record-7al_kvzq/install-record.txt --single-version-externally-managed --compile --install-headers /usr/local/include/python3.7m/openexr Check the logs for full command output.
~ ❯❯❯

With zlib and openexr installed via brew:

~ ❯❯❯ brew info zlib
zlib: stable 1.2.11 (bottled) [keg-only]
General-purpose lossless data-compression library
https://zlib.net/
/usr/local/Cellar/zlib/1.2.11 (12 files, 373KB)
  Poured from bottle on 2020-03-13 at 01:34:15
[...]
~ ❯❯❯ brew info openexr
openexr: stable 2.4.1 (bottled)
High dynamic-range image file format
https://www.openexr.com/
/usr/local/Cellar/openexr/2.4.1 (151 files, 6.8MB) *
  Poured from bottle on 2020-03-12 at 14:43:22
[...]

[SarahChane98]

Hi @SebastianGrans! I'm having the exact problem as you do. Have you solved the problem yet? Any chance that you could offer some tips? Thank you!

[SebastianGrans]

@SarahChane98: I didn't solve it, but I discovered that OpenCV can import EXR files as well.

You can install it via pip as the package opencv-python.

import cv2
im = cv2.imread('path/file.exr')

[SarahChane98]

Thank you so much! Just wondering, will Opencv output the same format as OpenEXR?

[SebastianGrans]

Somehow I ended up coming back to needing this package. I'm not exactly sure what's going on, but it has something to do with which C++ standard is used when compiling OpenEXR. Specifically we need to specify that C++11 should be used.

Installing OpenEXR on Linux works great but doesn't work on Mac. So it probably has something to do with Clang vs GCC.
The solution is rather simple.

1. Download the package: pip download openexr (This downloads e.g. OpenEXR-1.3.2.tar.gz)
2. Unpack the file: tar -xzvf OpenEXR-1.3.2.tar.gz
3. This creates a folder: OpenEXR-1.3.2/. Inside that folder is setup.py which we need to modify.
4. Modify the line extra_compile_args so that it looks like this: extra_compile_args=['-g', '-DVERSION="%s"' % version, '-std=c++11']) (Notice that we have added the flag for the C++11 standard).
5. While standing inside the folder, install the package by running pip install .

I'm not sure if this would have any consequences on other platforms, but maybe @jamesbowman could look into it?