opencv+c++实现的瘦脸算法

关键思想是《Image Deformation Using Moving Least Squares》这篇论文中提到的方法。
 

实现：

1>实现人脸关键点定位
 

2>实现论文中像素点的坐标变换

坐标变换源码：

void face_lift(Mat &src,const vector<Point2f>& landmarks,int change,const Rect &face)
{
	vector<Point2f> control_p = {landmarks[0],
				    landmarks[5],								            Point2f(face.x,face.y+face.height),
				    Point2f(face.x+face.width,face.y+face.height),
				    landmarks[11],
				    landmarks[16],
                                    landmarks[33],
                                    landmarks[62]
	};
	vector<Point2f> control_q = { landmarks[0],	
                                      landmarks[5],								              Point2f(landmarks[5].x + change,landmarks[5].y),					      Point2f(face.x,face.y + face.height),
				      Point2f(face.x + face.width,face.y + face.height),
                                      Point2f(landmarks[11].x-change,landmarks[11].y ),
				      landmarks[16],
				      landmarks[33],
                                      landmarks[62],
									};
	
	Mat pic=src.clone();
	

	
	for (int i =face.x; i <=face.x+face.width; ++i)
	{

		for (int j = landmarks[0].y;j< landmarks[8].y; ++j)
		{
		
			{
				vector<float> weight_p;								        vector<Point2f>::iterator itcp = control_p.begin();
				while (itcp != control_p.end())
				{
					double tmp;
					if (itcp->x != i || itcp->y != j)
						tmp = 1 / ((itcp->x - i)*(itcp->x - i) + (itcp->y - j)*(itcp->y - j));
				        else
						tmp = MAXNUM;
					weight_p.push_back(tmp);
					++itcp;
				}

				double px = 0, py = 0, qx = 0, qy = 0, tw = 0;
				itcp = control_p.begin();

				vector<float>::iterator itwp = weight_p.begin();
				vector<Point2f>::iterator itcq = control_q.begin();
				while (itcp != control_p.end())
				{
					px += (*itwp)*(itcp->x);
					py += (*itwp)*(itcp->y);
					qx += (*itwp)*(itcq->x);
					qy += (*itwp)*(itcq->y);

					tw += *itwp;
					++itcp;
					++itcq;
					++itwp;


				}
				px = px / tw;
				py = py / tw;
				qx = qx / tw;
				qy = qy / tw;

				Mat A = Mat::zeros(2, 1, CV_32FC1);
				Mat B = Mat::zeros(1, 2, CV_32FC1);
				Mat C = Mat::zeros(1, 2, CV_32FC1);
				Mat sumL = Mat::zeros(2, 2, CV_32FC1);
				Mat sumR = Mat::zeros(2, 2, CV_32FC1);
				Mat M, pos;
				for (int i = 0; i < weight_p.size(); ++i)
				{
					A.at<float>(0, 0) = (control_p[i].x - px);
					A.at<float>(1, 0) = (control_p[i].y - py);
					B.at<float>(0, 0) = weight_p[i] * ((control_p[i].x - px));
					B.at<float>(0, 1) = weight_p[i] * ((control_p[i].y - py));
					sumL += A * B;
					C.at<float>(0, 0) = weight_p[i] * (control_q[i].x - qx);
					C.at<float>(0, 1) = weight_p[i] * (control_q[i].y - qy);
					sumR += A * C;
				}
				M = sumL.inv()*sumR;


				B.at<float>(0, 0) = i - px;
				B.at<float>(0, 1) = j - py;
				C.at<float>(0, 0) = qx;
				C.at<float>(0, 1) = qy;
				pos = B * M + C;
				int row = pos.at<float>(0, 0);
				int col = pos.at<float>(0, 1);


				pic.at<Vec3b>(col, row)[0] = src.at<Vec3b>(j, i)[0];
				pic.at<Vec3b>(col, row)[1] = src.at<Vec3b>(j, i)[1];
				pic.at<Vec3b>(col, row)[2] = src.at<Vec3b>(j, i)[2];


			}

		}
	}
}

效果图：