build error

[XieWup]

When using the catkin build command, the terminal prints the following error:

WARNING: Your current environment's CMAKE_PREFIX_PATH is different from
the cached CMAKE_PREFIX_PATH used the last time this workspace was
built.

If you want to use a different CMAKE_PREFIX_PATH you should call catkin clean to remove all references to the previous CMAKE_PREFIX_PATH.

Cached CMAKE_PREFIX_PATH:
/home/liangs/anjoy_ws/devel:/opt/ros/melodic
Current CMAKE_PREFIX_PATH:
/home/liangs/anjoy_ws/devel/.private/catkin_tools_prebuild:/home/liangs/anjoy_ws/devel:/opt/ros/melodic

[build] Found '5' packages in 0.0 seconds.
[build] Updating package table.
Starting >>> depth_clustering

---

Errors << depth_clustering:make /home/liangs/anjoy_ws/logs/depth_clustering/build.make.000.log
/home/liangs/anjoy_ws/src/depth_clustering/src/utils/velodyne_utils.cpp: In function ‘cv::Mat depth_clustering::MatFromDepthPng(const string&)’:
/home/liangs/anjoy_ws/src/depth_clustering/src/utils/velodyne_utils.cpp:116:42: error: ‘CV_LOAD_IMAGE_ANYDEPTH’ was not declared in this scope
cv::Mat depth_image = cv::imread(path, CV_LOAD_IMAGE_ANYDEPTH);
^~~~~~~~~~~~~~~~~~~~~~
/home/liangs/anjoy_ws/src/depth_clustering/src/utils/velodyne_utils.cpp:116:42: note: suggested alternative: ‘CV_MAT_DEPTH’
cv::Mat depth_image = cv::imread(path, CV_LOAD_IMAGE_ANYDEPTH);
^~~~~~~~~~~~~~~~~~~~~~
CV_MAT_DEPTH
make[2]: *** [src/utils/CMakeFiles/velodyne_utils.dir/velodyne_utils.cpp.o] Error 1
make[1]: *** [src/utils/CMakeFiles/velodyne_utils.dir/all] Error 2
make: *** [all] Error 2
cd /home/liangs/anjoy_ws/build/depth_clustering; catkin build --get-env depth_clustering | catkin env -si /usr/bin/make --jobserver-fds=6,7 -j; cd -
...............................................................................
Failed << depth_clustering:make [ Exited with code 2 ]
Failed <<< depth_clustering [ 29.6 seconds ]
[build] Summary: 0 of 1 packages succeeded.
[build] Ignored: 4 packages were skipped or are blacklisted.
[build] Warnings: None.
[build] Abandoned: None.
[build] Failed: 1 packages failed.
[build] Runtime: 29.6 seconds total.
[build] Note: Workspace packages have changed, please re-source setup files to use them.

[XieWup]

1