According to the official guidelines, link: GitHub – wkentaro/label: image polygon annotation with python (polygon, rectangle, circle, line, point and image level flag annotation)

conda create --name=labelme python=3
source activate labelme
pip install labelme

Question 1:

gcc -pthread -B /home/XXX/fxp/envs/labelme/compiler_compat -Wno-unused-
result -Wsign-compare -DNDEBUG -g -fwrapv -O2 -Wall -fPIC -O2 -isystem 
/home/XXX/fxp/envs/labelme/include -fPIC -O2 -isystem 
/home/XXX/fxp/envs/labelme/include -fPIC -DFREETYPE_BUILD_TYPE=system -
DPY_ARRAY_UNIQUE_SYMBOL=MPL_matplotlib_ft2font_ARRAY_API -
DNPY_NO_DEPRECATED_API=NPY_1_7_API_VERSION -D__STDC_FORMAT_MACROS=1 -
Iextern/agg24-svn/include -I/home/XXX/fxp/envs/labelme/lib/python3.10/site-
packages/numpy/core/include -I/home/XXX/fxp/envs/labelme/include/python3.10
 -c src/checkdep_freetype2.c -o build/temp.linux-x86_64-cpython-
310/src/checkdep_freetype2.o
      src/checkdep_freetype2.c:3:6: error: #error "FreeType version 2.3 or higher 
is required. You may set the MPLLOCALFREETYPE environment variable to 1 to let 
Matplotlib download it."
           #error "FreeType version 2.3 or higher is required. \

            ^~~~~
      src/checkdep_freetype2.c:10:10: error: #include expects "FILENAME" or 
<FILENAME>
       #include FT_FREETYPE_H
                ^~~~~~~~~~~~~
      src/checkdep_freetype2.c:15:9: note: #pragma message: Compiling with FreeType version FREETYPE_MAJOR.FREETYPE_MINOR.FREETYPE_PATCH.
       #pragma message("Compiling with FreeType version " \
               ^~~~~~~
      src/checkdep_freetype2.c:18:4: error: #error "FreeType version 2.3 or higher
 is required. You may set the MPLLOCALFREETYPE environment variable to 1 to let Matplotlib download it."
         #error "FreeType version 2.3 or higher is required. \
          ^~~~~
      error: command '/usr/bin/gcc' failed with exit code 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.
╰─> matplotlib

note: This is an issue with the package mentioned above, not pip.
hint: See above for output from the failure.

Relevant dependent libraries need to be installed:

sudo apt-get update
sudo apt-get install libfreetype6-dev
sudo apt-get install pkg-config
sudo apt-get install libpng12-dev
sudo apt-get install pkg-config

Error 2 encountered:

labelme
[INFO   ] __init__:get_config:70 - Loading config file from: /home/XXX/.labelmerc
Traceback (most recent call last):
  File "/home/XXX/fxp/envs/labelme/lib/python3.10/site-packages/labelme/widgets/canvas.py", line 618, in paintEvent
    p.translate(self.offsetToCenter())
  File "/home/XXX/fxp/envs/labelme/lib/python3.10/site-packages/labelme/widgets/canvas.py", line 659, in offsetToCenter
    return QtCore.QPoint(x, y)
TypeError: arguments did not match any overloaded call:
  QPoint(): too many arguments
  QPoint(int, int): argument 1 has unexpected type 'float'
  QPoint(QPoint): argument 1 has unexpected type 'float'
Aborted (core dumped)

Reference link: https://github.com/wkentaro/labelme/issues/1006

I guess the python version is too high, so I recreated the virtual environment with pyhton = 3.9

conda create --prefix=/home/fxp/envs/labelme python=3.9 -y

The final installation is successful;