c++ - OpenCV cv::Mat to short* (avoiding memcpy) -

i have c++ function called else's c# application. input function given array of signed short integers, dimensions of image represents, , memory allocated returning data, namely array of signed short integers. represent function's header:

my_function (short* input, int height, int width, short* output) 

inside function create cv::mat input, this:

cv::mat mat_in = cv::mat (height, width, cv_16s, input); 

this mat_in converted cv_32f , processed opencv's cv::bilateralfilter. after returns cv::mat mat_out, convert data cv_16s (bilateralfilter accepts cv_8u , cv_32f). need convert cv::mat mat_out array of short integers may returned calling function. code:

my_function (short* input, int height, int width, short* output) {     mat mat_in_16s = mat (height, width, cv_16s, input);      mat mat_in_32f = mat (height, width, cv_32f);     mat mat_out_cv_32f = mat (height, width, cv_32f);      mat_in_16s.convertto (mat_in_32f, cv_32f);      bilateralfilter (mat_in_32f, mat_out_32f, 5, 160, 2);     mat mat_out_16s = mat (mat_in_16s.size(), mat_in_16s.type());     mat_out_32f.convertto (mat_out_16s, cv_16s);      return 0; } 

obviously, somewhere there @ end need data in mat_out_16s output. first try return reference:

output = &mat_out_16s.at<short>(0,0); 

but of course realised silly idea, mat_out_16s goes out of scope function returns, leaving output pointing @ emptiness. best attempt follows (from this question):

memcpy ((short*)output, (short*)mat_out_16s.data, height*width*sizeof(short)); 

now know, there better way? feels kind of inefficient copy data, don't see else can do. can't return cv::mat unfortunately. if there no better way, current memcpy method safe @ least? data 2-byte signed short integers, don't think there should issues padding, don't want run unpleasant surprises.

you can use constructor mat_out_16s:

mat::mat(size size, int type, void* data, size_t step=auto_step) 

so function be:

my_function (short* input, int height, int width, short* output) {     mat mat_in_16s = mat (height, width, cv_16s, input);      mat mat_in_32f = mat (height, width, cv_32f);     mat mat_out_cv_32f = mat (height, width, cv_32f);      mat_in_16s.convertto (mat_in_32f, cv_32f);      bilateralfilter (mat_in_32f, mat_out_32f, 5, 160, 2);     mat mat_out_16s = mat (mat_in_16s.size(), mat_in_16s.type(), output);     mat_out_32f.convertto (mat_out_16s, cv_16s);      return 0; }