I have built image v19.07.10, and added in package mjpg-streamer and opencv and all defined dependencies.
However when I update the CMakelists.txt file for mjpg-streamer to include input plugin opencv, it doesnt failt, it simply reports
PLUGIN_INPUT_OPENCV, Opencv input plugin (unmet dependencies)
The following OPTIONAL packages have not been found
I have build OpenCV on its own, and it does create the package in bin, so it seems ok.....
Had anybody any ideas?
openwrt-19.07 is discontinued and EOL for over two year by now, all bugs (of which there are bound to be quite serious security ones) are now yours and yours only.
Thanks for your help.
Looking at the makefiles for the latest branch in Git the issue will still be there for anyone trying this.
The fix (assuming no other version of opencv on the system) is to go to the built_dir for the opencv package, and to run make install. This will set up everything correctly and allow the application make to find the package.
Highgui is not built as standard and needs to removed from the package dependencies for plugin input_opencv in the makefile too. This should not be neeed anyway for embedded devices.