pip install dlib not working in Anaconda environment

Question

I'm follow a tutorial for getting an anaconda environment up and running with the following yml file . The problem is, I consistently encounter an error ONLY in this environment. I've tried running pip install dlib in both cmd and the base (root) Anaconda environment and they succeed. I installed CMake and C++ build tools for Visual Studio Community 2019. I'm unsure of what else to try, I've also verified I have my CMake bin path in my environment variables. Any idea of what I'm missing here?

I'm on Python 3.7.3 in the environment

    ERROR: Complete output from command 'C:\Users\Breju\anaconda3\envs\stylegan2\python.exe' -u -c 'import setuptools, tokenize;__file__='"'"'C:\\Users\\Breju\\AppData\\Local\\Temp\\pip-install-2pmurg4w\\dlib\\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 'C:\Users\Breju\AppData\Local\Temp\pip-wheel-wemf8s5l' --python-tag cp37:
  ERROR: running bdist_wheel
  running build
  running build_py
  package init file 'dlib\__init__.py' not found (or not a regular file)
  running build_ext
  Building extension for Python 3.7.3 (default, Apr 24 2019, 15:29:51) [MSC v.1915 64 bit (AMD64)]
  Invoking CMake setup: 'cmake C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python -DCMAKE_LIBRARY_OUTPUT_DIRECTORY=C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\lib.win-amd64-3.7 -DPYTHON_EXECUTABLE=C:\Users\Breju\anaconda3\envs\stylegan2\python.exe -DCMAKE_LIBRARY_OUTPUT_DIRECTORY_RELEASE=C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\lib.win-amd64-3.7 -A x64'
  -- Building for: Visual Studio 16 2019
  -- Selecting Windows SDK version 10.0.18362.0 to target Windows 10.0.19042.
  -- The C compiler identification is MSVC 19.29.30133.0
  -- The CXX compiler identification is MSVC 19.29.30133.0
  -- Detecting C compiler ABI info
  -- Detecting C compiler ABI info - done
  -- Check for working C compiler: C:/Program Files (x86)/Microsoft Visual Studio/2019/Community/VC/Tools/MSVC/14.29.30133/bin/Hostx64/x64/cl.exe - skipped
  -- Detecting C compile features
  -- Detecting C compile features - done
  -- Detecting CXX compiler ABI info
  -- Detecting CXX compiler ABI info - done
  -- Check for working CXX compiler: C:/Program Files (x86)/Microsoft Visual Studio/2019/Community/VC/Tools/MSVC/14.29.30133/bin/Hostx64/x64/cl.exe - skipped
  -- Detecting CXX compile features
  -- Detecting CXX compile features - done
  -- Found PythonInterp: C:/Users/Breju/anaconda3/envs/stylegan2/python.exe (found version "3.7.3")
  -- Found PythonLibs: C:/Users/Breju/anaconda3/envs/stylegan2/libs/Python37.lib
  -- pybind11 v2.2.2
  -- Using CMake version: 3.19.4
  -- Compiling dlib version: 19.18.0
  -- SSE4 instructions can be executed by the host processor.
  -- AVX instructions can be executed by the host processor.
  -- Looking for sys/types.h
  -- Looking for sys/types.h - found
  -- Looking for stdint.h
  -- Looking for stdint.h - found
  -- Looking for stddef.h
  -- Looking for stddef.h - found
  -- Check size of void*
  -- Check size of void* - done
  -- Enabling AVX instructions
  -- Searching for BLAS and LAPACK
  -- Searching for BLAS and LAPACK
  -- Looking for pthread.h
  -- Looking for pthread.h - not found
  -- Found Threads: TRUE
  CUDA_TOOLKIT_ROOT_DIR not found or specified
  -- Could NOT find CUDA (missing: CUDA_TOOLKIT_ROOT_DIR CUDA_NVCC_EXECUTABLE CUDA_INCLUDE_DIRS CUDA_CUDART_LIBRARY) (Required is at least version "7.5")
  -- DID NOT FIND CUDA
  -- Disabling CUDA support for dlib.  DLIB WILL NOT USE CUDA
  -- C++11 activated.
  -- Configuring done
  -- Generating done
  -- Build files have been written to: C:/Users/Breju/AppData/Local/Temp/pip-install-2pmurg4w/dlib/build/temp.win-amd64-3.7/Release
  Invoking CMake build: 'cmake --build . --config Release -- /m'
  Microsoft (R) Build Engine version 16.11.0+0538acc04 for .NET Framework
  Copyright (C) Microsoft Corporation. All rights reserved.

  C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\MSBuild\Microsoft\VC\v160\Microsoft.CppBuild.targets(517,5): warning MSB8029: The Intermediate directory or Output directory cannot reside under the Temporary directory as it could lead to issues with incremental build. [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\ZERO_CHECK.vcxproj]
    Checking Build System
  C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\MSBuild\Microsoft\VC\v160\Microsoft.CppBuild.targets(517,5): warning MSB8029: The Intermediate directory or Output directory cannot reside under the Temporary directory as it could lead to issues with incremental build. [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_build\dlib.vcxproj]
    Building Custom Rule C:/Users/Breju/AppData/Local/Temp/pip-install-2pmurg4w/dlib/dlib/CMakeLists.txt
    base64_kernel_1.cpp
    bigint_kernel_1.cpp
    bigint_kernel_2.cpp
    bit_stream_kernel_1.cpp
    entropy_decoder_kernel_1.cpp
    entropy_decoder_kernel_2.cpp
    entropy_encoder_kernel_1.cpp
    entropy_encoder_kernel_2.cpp
  C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\dlib\bigint\bigint_kernel_1.h(512,18): warning C4834: discarding return value of function with 'nodiscard' attribute (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\dlib\bigint\bigint_kernel_1.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_build\dlib.vcxproj]
    md5_kernel_1.cpp
  C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\dlib\bigint\bigint_kernel_1.h(524,17): warning C4834: discarding return value of function with 'nodiscard' attribute (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\dlib\bigint\bigint_kernel_1.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_build\dlib.vcxproj]
  C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\dlib\bigint\bigint_kernel_2.h(537,18): warning C4834: discarding return value of function with 'nodiscard' attribute (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\dlib\bigint\bigint_kernel_2.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_build\dlib.vcxproj]
  C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\dlib\bigint\bigint_kernel_2.h(549,17): warning C4834: discarding return value of function with 'nodiscard' attribute (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\dlib\bigint\bigint_kernel_2.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_build\dlib.vcxproj]
    tokenizer_kernel_1.cpp
    unicode.cpp
    image_dataset_metadata.cpp
    mnist.cpp
    global_function_search.cpp
    kalman_filter.cpp
    test_for_odr_violations.cpp
    auto.cpp
    sockets_kernel_1.cpp
    bsp.cpp
    dir_nav_kernel_1.cpp
    dir_nav_kernel_2.cpp
    dir_nav_extensions.cpp
    linker_kernel_1.cpp
    extra_logger_headers.cpp
    logger_kernel_1.cpp
    logger_config_file.cpp
    misc_api_kernel_1.cpp
    misc_api_kernel_2.cpp
    sockets_extensions.cpp
    sockets_kernel_2.cpp
    sockstreambuf.cpp
    sockstreambuf_unbuffered.cpp
    server_kernel.cpp
    server_iostream.cpp
    server_http.cpp
    multithreaded_object_extension.cpp
    threaded_object_extension.cpp
    threads_kernel_1.cpp
    threads_kernel_2.cpp
    threads_kernel_shared.cpp
    thread_pool_extension.cpp
    async.cpp
    timer.cpp
    stack_trace.cpp
    cpu_dlib.cpp
    tensor_tools.cpp
    fonts.cpp
    widgets.cpp
    drawable.cpp
    canvas_drawing.cpp
    style.cpp
    base_widgets.cpp
    gui_core_kernel_1.cpp
    gui_core_kernel_2.cpp
    png_loader.cpp
    save_png.cpp
    jpeg_loader.cpp
    save_jpeg.cpp
    arm_init.c
    filter_neon_intrinsics.c
    png.c
    pngerror.c
    pngget.c
    pngmem.c
    pngpread.c
    pngread.c
    pngrio.c
    pngrtran.c
    pngrutil.c
    pngset.c
    pngtrans.c
    pngwio.c
    pngwrite.c
    pngwtran.c
    pngwutil.c
    adler32.c
    compress.c
    crc32.c
    deflate.c
    gzclose.c
    gzlib.c
    gzread.c
    gzwrite.c
    infback.c
    inffast.c
    inflate.c
    inftrees.c
    trees.c
    uncompr.c
    zutil.c
    jaricom.c
    jcapimin.c
    jcapistd.c
    jcarith.c
    jccoefct.c
    jccolor.c
    jcdctmgr.c
    jchuff.c
    jcinit.c
    jcmainct.c
    jcmarker.c
    jcmaster.c
    jcomapi.c
    jcparam.c
    jcprepct.c
    jcsample.c
    jdapimin.c
    jdapistd.c
    jdarith.c
    jdatadst.c
    jdatasrc.c
    jdcoefct.c
    jdcolor.c
    jddctmgr.c
    jdhuff.c
  C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\dlib\external\libjpeg\jdatadst.c(185,60): warning C4267: '=': conversion from 'size_t' to 'unsigned long', possible loss of data [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_build\dlib.vcxproj]
    jdinput.c
    jdmainct.c
    jdmarker.c
    jdmaster.c
    jdmerge.c
    jdpostct.c
    jdsample.c
    jerror.c
    jfdctflt.c
    jfdctfst.c
  C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\dlib\external\libjpeg\jerror.c(193,5): warning C4996: 'sprintf': This function or variable may be unsafe. Consider using sprintf_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for details. [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_build\dlib.vcxproj]
  C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\dlib\external\libjpeg\jerror.c(195,5): warning C4996: 'sprintf': This function or variable may be unsafe. Consider using sprintf_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for details. [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_build\dlib.vcxproj]
    jfdctint.c
    jidctflt.c
    jidctfst.c
    jidctint.c
    jmemmgr.c
    jmemnobs.c
    jquant1.c
  C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\dlib\external\libjpeg\jmemmgr.c(307,53): warning C4267: '+=': conversion from 'size_t' to 'long', possible loss of data [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_build\dlib.vcxproj]
  C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\dlib\external\libjpeg\jmemmgr.c(367,70): warning C4267: '+=': conversion from 'size_t' to 'long', possible loss of data [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_build\dlib.vcxproj]
  C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\dlib\external\libjpeg\jmemmgr.c(977,46): warning C4267: '-=': conversion from 'size_t' to 'long', possible loss of data [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_build\dlib.vcxproj]
    jquant2.c
    jutils.c
  C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\dlib\external\libjpeg\jmemmgr.c(991,46): warning C4267: '-=': conversion from 'size_t' to 'long', possible loss of data [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_build\dlib.vcxproj]
  C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\dlib\external\libjpeg\jmemmgr.c(1107,19): warning C4996: 'getenv': This function or variable may be unsafe. Consider using _dupenv_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for details. [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_build\dlib.vcxproj]
  C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\dlib\external\libjpeg\jmemmgr.c(1110,11): warning C4996: 'sscanf': This function or variable may be unsafe. Consider using sscanf_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for details. [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_build\dlib.vcxproj]
    dlib.vcxproj -> C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_build\Release\dlib19.18.0_release_64bit_msvc1929.lib
  C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\MSBuild\Microsoft\VC\v160\Microsoft.CppBuild.targets(517,5): warning MSB8029: The Intermediate directory or Output directory cannot reside under the Temporary directory as it could lead to issues with incremental build. [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
    Building Custom Rule C:/Users/Breju/AppData/Local/Temp/pip-install-2pmurg4w/dlib/tools/python/CMakeLists.txt
    dlib.cpp
    matrix.cpp
    vector.cpp
    svm_c_trainer.cpp
    svm_rank_trainer.cpp
    decision_functions.cpp
    other.cpp
    basic.cpp
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\vector.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\dlib.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\decision_functions.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\basic.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\svm_rank_trainer.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\other.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\svm_c_trainer.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
    cca.cpp
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\matrix.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
    sequence_segmenter.cpp
    svm_struct.cpp
    image.cpp
    image2.cpp
    image3.cpp
    image4.cpp
    rectangles.cpp
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\cca.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\sequence_segmenter.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\image2.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
    object_detection.cpp
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\svm_struct.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\image.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\image4.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\image3.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\rectangles.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
    shape_predictor.cpp
    correlation_tracker.cpp
    face_recognition.cpp
    cnn_face_detector.cpp
    global_optimization.cpp
    image_dataset_metadata.cpp
    numpy_returns.cpp
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\object_detection.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\shape_predictor.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\correlation_tracker.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\face_recognition.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\cnn_face_detector.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\global_optimization.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\image_dataset_metadata.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\numpy_returns.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
    line.cpp
    gui.cpp
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\line.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
  C:\Users\Breju\anaconda3\Library\include\gif_lib.h(286,61): error C2734: 'GifAsciiTable8x8': 'const' object must be initialized if not 'extern' (compiling source file C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\tools\python\src\gui.cpp) [C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\build\temp.win-amd64-3.7\Release\dlib_python.vcxproj]
  Traceback (most recent call last):
    File "<string>", line 1, in <module>
    File "C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\setup.py", line 261, in <module>
      'Topic :: Software Development',
    File "C:\Users\Breju\anaconda3\envs\stylegan2\lib\site-packages\setuptools\__init__.py", line 145, in setup
      return distutils.core.setup(**attrs)
    File "C:\Users\Breju\anaconda3\envs\stylegan2\lib\distutils\core.py", line 148, in setup
      dist.run_commands()
    File "C:\Users\Breju\anaconda3\envs\stylegan2\lib\distutils\dist.py", line 966, in run_commands
      self.run_command(cmd)
    File "C:\Users\Breju\anaconda3\envs\stylegan2\lib\distutils\dist.py", line 985, in run_command
      cmd_obj.run()
    File "C:\Users\Breju\anaconda3\envs\stylegan2\lib\site-packages\wheel\bdist_wheel.py", line 192, in run
      self.run_command('build')
    File "C:\Users\Breju\anaconda3\envs\stylegan2\lib\distutils\cmd.py", line 313, in run_command
      self.distribution.run_command(command)
    File "C:\Users\Breju\anaconda3\envs\stylegan2\lib\distutils\dist.py", line 985, in run_command
      cmd_obj.run()
    File "C:\Users\Breju\anaconda3\envs\stylegan2\lib\distutils\command\build.py", line 135, in run
      self.run_command(cmd_name)
    File "C:\Users\Breju\anaconda3\envs\stylegan2\lib\distutils\cmd.py", line 313, in run_command
      self.distribution.run_command(command)
    File "C:\Users\Breju\anaconda3\envs\stylegan2\lib\distutils\dist.py", line 985, in run_command
      cmd_obj.run()
    File "C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\setup.py", line 135, in run
      self.build_extension(ext)
    File "C:\Users\Breju\AppData\Local\Temp\pip-install-2pmurg4w\dlib\setup.py", line 175, in build_extension
      subprocess.check_call(cmake_build, cwd=build_folder)
    File "C:\Users\Breju\anaconda3\envs\stylegan2\lib\subprocess.py", line 347, in check_call
      raise CalledProcessError(retcode, cmd)
  subprocess.CalledProcessError: Command '['cmake', '--build', '.', '--config', 'Release', '--', '/m']' returned non-zero exit status 1.
  ----------------------------------------
  ERROR: Failed building wheel for dlib

Answer 1

Try to create a New virtual environment in Anaconda by running the following code in command line

conda create --name opencv-env python=3.6

After that, activate the environment

conda activate opencv-env

And finally, run the following command to install OpenCV and other important packages

pip install numpy scipy matplotlib scikit-learn (spyder/jupyter or whatever environment you are using)

pip install opencv-contrib-python

pip install dlib

If after that you still get an error asking you to update Virtual Studio that supports C++11, run the below command

pip install https://pypi.python.org/packages/da/06/bd3e241c4eb0a662914b3b4875fc52dd176a9db0d4a2c915ac2ad8800e9e/dlib-19.7.0-cp36-cp36m-win_amd64.whl#md5=b7330a5b2d46420343fbed5df69e6a3f