cvmathfuncs.cpp.svn-base

来自「非结构化路识别」· SVN-BASE 代码 · 共 71 行

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#include "_cv.h"

#define ICV_MATH_BLOCK_SIZE  256

#define _CV_SQRT_MAGIC     0xbe6f0000

#define _CV_SQRT_MAGIC_DBL CV_BIG_UINT(0xbfcd460000000000)

#define _CV_ATAN_CF0  (-15.8131890796f)
#define _CV_ATAN_CF1  (61.0941945596f)
#define _CV_ATAN_CF2  0.f /*(-0.140500406322f)*/

static const float icvAtanTab[8] = { 0.f + _CV_ATAN_CF2, 90.f - _CV_ATAN_CF2,
    180.f - _CV_ATAN_CF2, 90.f + _CV_ATAN_CF2,
    360.f - _CV_ATAN_CF2, 270.f + _CV_ATAN_CF2,
    180.f + _CV_ATAN_CF2, 270.f - _CV_ATAN_CF2
};

static const int icvAtanSign[8] =
    { 0, 0x80000000, 0x80000000, 0, 0x80000000, 0, 0, 0x80000000 };

/*F///////////////////////////////////////////////////////////////////////////////////////
//    Name:    icvFastAcrtan32f
//    Purpose: fast inaccurate arctangent approximation
//    Context:
//    Parameters:
//      y - ordinate
//      x - abscissa
//    Returns:
//      The angle of vector (x,y) in degrees (0