Pass pointer between python and C++

Python
7

if all you need in python is to “pass around” your cuda workspace vectors
(as in: A() produces it, B() consumes it, and noone tries to “peek into it” from python inbetween),
you could wrap it opaquely into some struct:


// the struct is exposed to python, the content not so !
struct CV_EXPORTS_W Workspace {
	vector<uchar*> workspace;
};

CV_EXPORTS_W Ptr<Workspace> init_workspace() {
	Ptr<Workspace> ws = makePtr<Workspace>();
	// ... fill ws->workspace
	return ws;
}

CV_EXPORTS_W bool imencode( const String& ext, InputArray img,
CV_OUT std::vector& buf,
const std::vector& params = std::vector(),
CV_IN Ptr<Workspace> workspace) {
	// do something with workspace->workspace;
}

usage from python would be as simple as:

ws = init_workspace()
...
cv2.imencode(ext,buffer,params,ws)
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