/*F///////////////////////////////////////////////////////////////////////////////////////
 //    Name:       cvSnakeImage
 //    Purpose:    Updates active contour in order to minimize its cummulative (internal
 //                and external) energy.
 //    Context:
 //    Parameters:
 //      src - source image that represent external energy.
 //      points - array of points in the snake.
 //      length - number of points
 //      alpha, beta, gamma - weights of different energy components
 //      coeffUsage - if it is CV_ARRAY then previous three parameters are array of 
 //                   <length> elements, otherwise each of them is a pointer to
 //                   scalar values.
 //      win - half-size of search window. 
 //      criteria - termination criteria.
 //      calcGradient - if not 0, the function uses magnitude of the source image gradient
 //                     as external energy, otherwise the source image pixel values
 //                     are just used for this purpose.  
 //    Returns:
 //    Notes:
 //F*/
 OPENCVAPI  void  cvSnakeImage( IplImage* src, CvPoint* points,
                             int  length, float* alpha,
                             float* beta, float* gamma,
                             CvCoeffType coeffUsage, CvSize  win,
                             CvTermCriteria criteria, int calcGradient CV_DEFAULT(1));