[Bug] opencv on linux

Nobody has claimed this yet.

After doing the manual install on the Linux setup guide and attempting to run app.py, I encountered this issue
sd-inf) _______@______:~/github/stablediffusion-infinity$ python app.py --local_model /home/user/checkpoint/model.ckpt
Compiling and loading c extensions from "/home/_____/github/stablediffusion-infinity/PyPatchMatch".
rm -rf build/obj libpatchmatch.so
Package opencv was not found in the pkg-config search path.
Perhaps you should add the directory containing `opencv.pc'
to the PKG_CONFIG_PATH environment variable
No package 'opencv' found
mkdir: created directory 'build/obj'
mkdir: created directory 'build/obj/csrc/'
[dep] csrc/pyinterface.cpp ...
Package opencv was not found in the pkg-config search path.
Perhaps you should add the directory containing `opencv.pc'
to the PKG_CONFIG_PATH environment variable
No package 'opencv' found
[dep] csrc/masked_image.cpp ...
Package opencv was not found in the pkg-config search path.
Perhaps you should add the directory containing `opencv.pc'
to the PKG_CONFIG_PATH environment variable
No package 'opencv' found
[dep] csrc/inpaint.cpp ...
Package opencv was not found in the pkg-config search path.
Perhaps you should add the directory containing `opencv.pc'
to the PKG_CONFIG_PATH environment variable
No package 'opencv' found
[dep] csrc/nnf.cpp ...
Package opencv was not found in the pkg-config search path.
Perhaps you should add the directory containing `opencv.pc'
to the PKG_CONFIG_PATH environment variable
No package 'opencv' found
[CC] csrc/nnf.cpp ...
In file included from csrc/nnf.cpp:5:
csrc/masked_image.h:3:10: fatal error: opencv2/core.hpp: No such file or directory
3 | #include
| ^~~~~~~~~~~~~~~~~~
compilation terminated.
make: *** [Makefile:33: build/obj/csrc/nnf.o] Error 1
patch_match compiling failed, will fall back to edge_pad
No module named 'fpie' so PhotometricCorrection is disabled
Running on local URL: _______________

To create a public link, set `share=True` in `launch()`.
I've tried fresh installs and running things multiple times, would like to know how to fix this

Start with the Linux setup guide, app.py, and PyPatchMatch/Makefile, especially the rule reported at Makefile:33. Reproduce the app.py command and inspect how the OpenCV dependency is discovered during the PyPatchMatch build. Done means the extension compiles without the missing-header error and app.py starts successfully on Linux.

Written by the indexing model from the issue text.