OpenCV函数学习——distancetransform函数之距离变换
Opencv中distanceTransform方法用于计算图像中每一个非零点距离离自己最近的零点的距离,distanceTransform的第二个Mat矩阵参数dst保存了每一个点与最近的零点的距离信息,图像上越亮的点,代表了离零点的距离越远。
官方文档
/** @overload
@param src 8-bit, single-channel (binary) source image.
@param dst Output image with calculated distances. It is a 8-bit or 32-bit floating-point,
single-channel image of the same size as src .
@param distanceType Type of distance, see #DistanceTypes
@param maskSize Size of the distance transform mask, see #DistanceTransformMasks. In case of the
#DIST_L1 or #DIST_C distance type, the parameter is forced to 3 because a \f$3\times 3\f$ mask gives
the same result as \f$5\times 5\f$ or any larger aperture.
@param dstType Type of output image. It can be CV_8U or CV_32F. Type CV_8U can be used only for
the first variant of the function and distanceType == #DIST_L1.
*/
CV_EXPORTS_W void distanceTransform( InputArray src, OutputArray dst,
int distanceType, int maskSize, int dstType=CV_32F);
enum DistanceTypes {
DIST_USER = -1, //!< User defined distance
DIST_L1 = 1, //!< distance = |x1-x2| + |y1-y2|
DIST_L2 = 2, //!< the simple euclidean distance
DIST_C = 3, //!< distance = max(|x1-x2|,|y1-y2|)
DIST_L12 = 4, //!< L1-L2 metric: distance = 2(sqrt(1+x*x/2) - 1))
DIST_FAIR = 5, //!< distance = c^2(|x|/c-log(1+|x|/c)), c = 1.3998
DIST_WELSCH = 6, //!< distance = c^2/2(1-exp(-(x/c)^2)), c = 2.9846
DIST_HUBER = 7 //!< distance = |x|<c ? x^2/2 : c(|x|-c/2), c=1.345
};