dlib安装错误: 缺少Visual C++

在Windows上使用pip安装dlib库时，遇到了以下错误：

'Downloading http://pypi.doubanio.com/packages/e5/3b/7a8522a5c2ef6ff6252e46b0788b3d2c2280198c49d6ecf3b576b171045f/dlib-19.24.0.tar.gz (3.2 MB) ---------------------------------------- 3.2/3.2 MB 6.2 MB/s eta 0:00:00 Preparing metadata (setup.py) ... done Building wheels for collected packages: dlib Building wheel for dlib (setup.py) ... error error: subprocess-exited-with-error

× python setup.py bdist_wheel did not run successfully. │ exit code: 1 ╰─> [59 lines of output] running bdist_wheel running build running build_py package init file 'tools/python/dlib/init.py' not found (or not a regular file) running build_ext Building extension for Python 3.8.7rc1 (tags/v3.8.7rc1:e320109, Dec 7 2020, 16:42:32) [MSC v.1927 64 bit (AMD64)] Invoking CMake setup: 'cmake C:\Users\fanzhu\AppData\Local\Temp\pip-install-av51osu4\dlib_dff1a80727114c9796f2a04191961e98\tools\python -DCMAKE_LIBRARY_OUTPUT_DIRECTORY=C:\Users\fanzhu\AppData\Local\Temp\pip-install-av51osu4\dlib_dff1a80727114c9796f2a04191961e98\build\lib.win-amd64-3.8 -DPYTHON_EXECUTABLE=c:\users\fanzhu\appdata\local\programs\python\python38\python.exe -DCMAKE_LIBRARY_OUTPUT_DIRECTORY_RELEASE=C:\Users\fanzhu\AppData\Local\Temp\pip-install-av51osu4\dlib_dff1a80727114c9796f2a04191961e98\build\lib.win-amd64-3.8 -A x64' -- Building for: NMake Makefiles CMake Error at CMakeLists.txt:5 (message):

    !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!


    You must use Visual Studio to build a python extension on windows.  If you
    are getting this error it means you have not installed Visual C++.  Note
    that there are many flavors of Visual Studio, like Visual Studio for C#
    development.  You need to install Visual Studio for C++.


    !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!



  -- Configuring incomplete, errors occurred!
  Traceback (most recent call last):
    File "<string>", line 2, in <module>
    File "<pip-setuptools-caller>", line 34, in <module>
    File "C:\Users\fanzhu\AppData\Local\Temp\pip-install-av51osu4\dlib_dff1a80727114c9796f2a04191961e98\setup.py", line 222, in <module>
      setup(
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\site-packages\setuptools\__init__.py", line 165, in setup
      return distutils.core.setup(**attrs)
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\distutils\core.py", line 148, in setup
      dist.run_commands()
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\distutils\dist.py", line 966, in run_commands
      self.run_command(cmd)
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\distutils\dist.py", line 985, in run_command
      cmd_obj.run()
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\site-packages\wheel\bdist_wheel.py", line 343, in run
      self.run_command("build")
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\distutils\cmd.py", line 313, in run_command
      self.distribution.run_command(command)
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\distutils\dist.py", line 985, in run_command
      cmd_obj.run()
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\distutils\command\build.py", line 135, in run
      self.run_command(cmd_name)
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\distutils\cmd.py", line 313, in run_command
      self.distribution.run_command(command)
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\distutils\dist.py", line 985, in run_command
      cmd_obj.run()
    File "C:\Users\fanzhu\AppData\Local\Temp\pip-install-av51osu4\dlib_dff1a80727114c9796f2a04191961e98\setup.py", line 134, in run
      self.build_extension(ext)
    File "C:\Users\fanzhu\AppData\Local\Temp\pip-install-av51osu4\dlib_dff1a80727114c9796f2a04191961e98\setup.py", line 171, in build_extension
      subprocess.check_call(cmake_setup, cwd=build_folder)
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\subprocess.py", line 364, in check_call
      raise CalledProcessError(retcode, cmd)
  subprocess.CalledProcessError: Command '[‘cmake’, ‘C:\Users\fanzhu\AppData\Local\Temp\pip-install-av51osu4\dlib_dff1a80727114c9796f2a04191961e98\tools\python’, ‘-DCMAKE_LIBRARY_OUTPUT_DIRECTORY=C:\Users\fanzhu\AppData\Local\Temp\pip-install-av51osu4\dlib_dff1a80727114c9796f2a04191961e98\build\lib.win-amd64-3.8’, ‘-DPYTHON_EXECUTABLE=c:\users\fanzhu\appdata\local\programs\python\python38\python.exe’, ‘-DCMAKE_LIBRARY_OUTPUT_DIRECTORY_RELEASE=C:\Users\fanzhu\AppData\Local\Temp\pip-install-av51osu4\dlib_dff1a80727114c9796f2a04191961e98\build\lib.win-amd64-3.8’, ‘-A’, ‘x64’]' returned non-zero exit status 1.
  [end of output]

note: This error originates from a subprocess, and is likely not a problem with pip. ERROR: Failed building wheel for dlib Running setup.py clean for dlib Failed to build dlib WARNING: Ignoring invalid distribution -ip (c:\users\fanzhu\appdata\local\programs\python\python38\lib\site-packages) Installing collected packages: dlib Running setup.py install for dlib ... error error: subprocess-exited-with-error

× Running setup.py install for dlib did not run successfully. │ exit code: 1 ╰─> [61 lines of output] running install running build running build_py package init file 'tools/python/dlib/init.py' not found (or not a regular file) running build_ext Building extension for Python 3.8.7rc1 (tags/v3.8.7rc1:e320109, Dec 7 2020, 16:42:32) [MSC v.1927 64 bit (AMD64)] Invoking CMake setup: 'cmake C:\Users\fanzhu\AppData\Local\Temp\pip-install-av51osu4\dlib_dff1a80727114c9796f2a04191961e98\tools\python -DCMAKE_LIBRARY_OUTPUT_DIRECTORY=C:\Users\fanzhu\AppData\Local\Temp\pip-install-av51osu4\dlib_dff1a80727114c9796f2a04191961e98\build\lib.win-amd64-3.8 -DPYTHON_EXECUTABLE=c:\users\fanzhu\appdata\local\programs\python\python38\python.exe -DCMAKE_LIBRARY_OUTPUT_DIRECTORY_RELEASE=C:\Users\fanzhu\AppData\Local\Temp\pip-install-av51osu4\dlib_dff1a80727114c9796f2a04191961e98\build\lib.win-amd64-3.8 -A x64' -- Building for: NMake Makefiles CMake Error at CMakeLists.txt:5 (message):

    !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!


    You must use Visual Studio to build a python extension on windows.  If you
    are getting this error it means you have not installed Visual C++.  Note
    that there are many flavors of Visual Studio, like Visual Studio for C#
    development.  You need to install Visual Studio for C++.


    !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!



  -- Configuring incomplete, errors occurred!
  Traceback (most recent call last):
    File "<string>", line 2, in <module>
    File "<pip-setuptools-caller>", line 34, in <module>
    File "C:\Users\fanzhu\AppData\Local\Temp\pip-install-av51osu4\dlib_dff1a80727114c9796f2a04191961e98\setup.py", line 222, in <module>
      setup(
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\site-packages\setuptools\__init__.py", line 165, in setup
      return distutils.core.setup(**attrs)
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\distutils\core.py", line 148, in setup
      dist.run_commands()
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\distutils\dist.py", line 966, in run_commands
      self.run_command(cmd)
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\distutils\dist.py", line 985, in run_command
      cmd_obj.run()
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\site-packages\setuptools\command\install.py", line 61, in run
      return orig.install.run(self)
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\distutils\command\install.py", line 545, in run
      self.run_command('build')
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\distutils\cmd.py", line 313, in run_command
      self.distribution.run_command(command)
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\distutils\dist.py", line 985, in run_command
      cmd_obj.run()
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\distutils\command\build.py", line 135, in run
      self.run_command(cmd_name)
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\distutils\cmd.py", line 313, in run_command
      self.distribution.run_command(command)
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\distutils\dist.py", line 985, in run_command
      cmd_obj.run()
    File "C:\Users\fanzhu\AppData\Local\Temp\pip-install-av51osu4\dlib_dff1a80727114c9796f2a04191961e98\setup.py", line 134, in run
      self.build_extension(ext)
    File "C:\Users\fanzhu\AppData\Local\Temp\pip-install-av51osu4\dlib_dff1a80727114c9796f2a04191961e98\setup.py", line 171, in build_extension
      subprocess.check_call(cmake_setup, cwd=build_folder)
    File "c:\users\fanzhu\appdata\local\programs\python\python38\lib\subprocess.py", line 364, in check_call
      raise CalledProcessError(retcode, cmd)
  subprocess.CalledProcessError: Command '[‘cmake’, ‘C:\Users\fanzhu\AppData\Local\Temp\pip-install-av51osu4\dlib_dff1a80727114c9796f2a04191961e98\tools\python’, ‘-DCMAKE_LIBRARY_OUTPUT_DIRECTORY=C:\Users\fanzhu\AppData\Local\Temp\pip-install-av51osu4\dlib_dff1a80727114c9796f2a04191961e98\build\lib.win-amd64-3.8’, ‘-DPYTHON_EXECUTABLE=c:\users\fanzhu\appdata\local\programs\python\python38\python.exe’, ‘-DCMAKE_LIBRARY_OUTPUT_DIRECTORY_RELEASE=C:\Users\fanzhu\AppData\Local\Temp\pip-install-av51osu4\dlib_dff1a80727114c9796f2a04191961e98\build\lib.win-amd64-3.8’, ‘-A’, ‘x64’]' returned non-zero exit status 1.
  [end of output]

note: This error originates from a subprocess, and is likely not a problem with pip. error: legacy-install-failure

× Encountered error while trying to install package. ╰─> dlib

note: This is an issue with the package mentioned above, not pip. hint: See above for output from the failure. WARNING: Ignoring invalid distribution -ip (c:\users\fanzhu\appdata\local\programs\python\python38\lib\site-packages) WARNING: Ignoring invalid distribution -ip (c:\users\fanzhu\appdata\local\programs\python\python38\lib\site-packages) WARNING: Ignoring invalid distribution -ip (c:\users\fanzhu\appdata\local\programs\python\python38\lib\site-packages) 这个报错内容：

是因为你没有安装Visual C++或者安装的Visual C++版本不正确。请安装Visual Studio for C++并重新运行安装命令。