c++ - How to generate a cv::Mat type code? -

i've been using c-style api generate opencv type codes. example:

cv::mat(h, w, cv_8uc2); 

cv_8uc2 macro defined in types_c.h (deprecated?):

#define cv_maketype(depth,cn) (cv_mat_depth(depth) + (((cn)-1) << cv_cn_shift)) 

is there similar type code generation function in c++ api,

mat m(w,h, cv::type(vec<unsigned char, 2>).typecode()) ? 

as said in comments, cv_maketype not deprecated, , afaik standard way of generating "type codes".

however (and fun), alternative, more c++-ish, way of generating arbitrary codes (still in compile time) can achieved using tmp...

template <int depth,           int cn> struct make_type {     enum {        // (yes, same expression used cv_maketype)        value = ((depth) & cv_mat_depth_mask) + (((cn)-1) << cv_cn_shift)     }; };  // can check works same good, old `cv_maketype`      cout << make_type<cv_8u,2>::value << " "<< cv_maketype(cv_8u,2) << endl; 

... don't this. while tmp fun , amazing, cv_maketype right way of doing things in case.

edit: opencv has own type traits utilities. in core/traits.hpp can find class datatype:

the datatype class used provide description of ... primitive data types without adding fields or methods corresponding classes (and impossible add primitive c/c++ data types). technique known in c++ class traits. not datatype used specialized versions ... main purpose of class convert compilation-time type information opencv-compatible data type identifier ...

so, such traits used tell opencv data type working with, if such type not native opencv.