網上查了很多,發現查資料不如查源碼
以Cv為開頭的類,都是不含有具體數據的(僅僅存儲指針)
CvMat
typedef struct CvMat { int type; int step; /* for internal use only */ int* refcount; int hdr_refcount; union { uchar* ptr; short* s; int* i; float* fl; double* db; } data;#ifdef __cplusplus union { int rows; int height; }; union { int cols; int width; };#else int rows; int cols;#endif}CvMat;CV_INLINE CvMat cvMat( int rows, int cols, int type, void* data CV_DEFAULT(NULL)) { CvMat m; assert( (unsigned)CV_MAT_DEPTH(type) <= CV_64F ); type = CV_MAT_TYPE(type); m.type = CV_MAT_MAGIC_VAL | CV_MAT_CONT_FLAG | type; m.cols = cols; m.rows = rows; m.step = m.cols*CV_ELEM_SIZE(type); m.data.ptr = (uchar*)data; m.refcount = NULL; m.hdr_refcount = 0; return m; }
CV_INLINE double cvmGet( const CvMat* mat, int row, int col ) {//低效率訪問! int type; type = CV_MAT_TYPE(mat->type); assert( (unsigned)row < (unsigned)mat->rows && (unsigned)col < (unsigned)mat->cols ); if( type == CV_32FC1 ) return ((float*)(void*)(mat->data.ptr + (size_t)mat->step*row))[col]; else { assert( type == CV_64FC1 ); return ((double*)(void*)(mat->data.ptr + (size_t)mat->step*row))[col]; } } CV_INLINE void cvmSet( CvMat* mat, int row, int col, double value ) { int type; type = CV_MAT_TYPE(mat->type); assert( (unsigned)row < (unsigned)mat->rows && (unsigned)col < (unsigned)mat->cols ); if( type == CV_32FC1 ) ((float*)(void*)(mat->data.ptr + (size_t)mat->step*row))[col] = (float)value; else { assert( type == CV_64FC1 ); ((double*)(void*)(mat->data.ptr + (size_t)mat->step*row))[col] = (double)value; } }typedef struct CvMatND { int type; int dims; int* refcount; int hdr_refcount; union { uchar* ptr; float* fl; double* db; int* i; short* s; } data; struct { int size; int step; } dim[CV_MAX_DIM]; } CvMatND;/* Basic element of the file storage - scalar or collection: */ typedef struct CvFileNode { int tag; struct CvTypeInfo* info; /* type information (only for user-defined object, for others it is 0) */ union { double f; /* scalar floating-point number */ int i; /* scalar integer number */ CvString str; /* text string */ CvSeq* seq; /* sequence (ordered collection of file nodes) */ CvFileNodeHash* map; /* map (collection of named file nodes) */ } data; } CvFileNode;