Linux环境下Python Pillow库Img.show()调用报错求助

我在Linux环境下使用Python的Pillow库编写代码，期望通过图片查看器打开图片，代码如下：

from PIL import Image
im = Image.open('hi.png')
im.show()

但运行时出现报错，错误信息如下：

Traceback (most recent call last):
  File "/home/kd/Documents/python/modules/pillow_image.py", line 3, in <module>
    im.show()
  File "/usr/lib/python3/dist-packages/PIL/Image.py", line 2146, in show
    _show(self, title=title, command=command)
  File "/usr/lib/python3/dist-packages/PIL/Image.py", line 3085, in _show
    _showxv(image, **options)
  File "/usr/lib/python3/dist-packages/PIL/Image.py", line 3091, in _showxv
    ImageShow.show(image, title, **options)
  File "/usr/lib/python3/dist-packages/PIL/ImageShow.py", line 47, in show
    if viewer.show(image, title=title, **options):
  File "/usr/lib/python3/dist-packages/PIL/ImageShow.py", line 67, in show
    return self.show_image(image, **options)
  File "/usr/lib/python3/dist-packages/PIL/ImageShow.py", line 87, in show_image
    return self.show_file(self.save_image(image), **options)
  File "/usr/lib/python3/dist-packages/PIL/ImageShow.py", line 168, in show_file
    subprocess.Popen(args)
  File "/usr/lib/python3.8/subprocess.py", line 858, in __init__
    self._execute_child(args, executable, preexec_fn, close_fds,
  File "/usr/lib/python3.8/subprocess.py", line 1639, in _execute_child
    self.pid = _posixsubprocess.fork_exec(
TypeError: expected str, bytes or os.PathLike object, not NoneType
[Finished in 178ms with exit code 1]

这个错误是因为Pillow无法找到系统中的图片查看器程序，导致调用subprocess时传入了None值。可以通过以下方式解决：

• 安装系统图片查看器
  根据你的Linux发行版选择对应命令安装：

  • Debian/Ubuntu系：

    sudo apt update && sudo apt install eog
    

  • Fedora/RHEL系：

    sudo dnf install eog
    

  • Arch系：

    sudo pacman -S eog
    

  也可以选择轻量查看器feh：

  # Debian/Ubuntu
  sudo apt install feh
  # Fedora
  sudo dnf install feh
  # Arch
  sudo pacman -S feh
  

• 手动指定查看器命令
  修改代码，在show()方法中直接指定要用的查看器：

  from PIL import Image
  im = Image.open('hi.png')
  # 用eog打开
  im.show(command='eog')
  # 或者用feh
  # im.show(command='feh')
  

• 设置环境变量指定默认查看器
  临时设置（当前终端有效）：

  export PIL_IMAGE_VIEWER=eog
  

  运行脚本前执行上述命令即可。若要永久生效，可将该命令添加到~/.bashrc或~/.zshrc文件中。
  也可以在Python脚本内直接设置：

  import os
  from PIL import Image
  os.environ['PIL_IMAGE_VIEWER'] = 'eog'
  im = Image.open('hi.png')
  im.show()
  

内容的提问来源于stack exchange，提问作者Nirjhar Das