虚拟视点图像的生成001

╰+攻爆jí腚メ 2022-08-08 05:28 147阅读 0赞

这是虚拟视点图像生成的第一篇博客，希望自己能坚持下来。

1. 实验环境

Win8-----vs2013-----opencv2.4.11

2. 实验材料

微软亚洲研究院多视点视频序列

下载地址：

[http://research.microsoft.com/en-us/downloads/5e4675af-03f4-4b16-b3bc-a85c5bafb21d/][http_research.microsoft.com_en-us_downloads_5e4675af-03f4-4b16-b3bc-a85c5bafb21d]

使用微软亚洲研究院的多视点视频序列，由视点0和视点2生成虚拟视点1的过程，采用opencv库来辅助开发，主要的成果有：

1，由参考视点0的彩色图像和深度图像生成虚拟视点1的彩色图像和深度图像，中间用z-buffer算法解决遮挡问题；

2，在1的基础上，由参考视点2的彩色图像和深度图像生成虚拟视点1的彩色图像和深度图像。

3，为解决裂缝问题，用中值滤波来滤波彩色图像和深度图像。

4，采用的是双向映射。

原始图像

![Center][]

生成的图像

![Center 1][]

源代码

#ifndef _wrapingOf3D1
    #define _wrapingOf3D1
    #include<iostream>
    #include<opencv2\opencv.hpp>
    class Histogram1D{
    private:
    	int histSize[1];
    	float hranges[2];
    	const float *ranges[1];
    	int channels[1];
    public:
    	Histogram1D(){
    		histSize[0] = 256;
    		hranges[0] = 0.0;
    		hranges[1] = 255.0;
    		ranges[0] = hranges;
    		channels[0] = 0;
    	}
    	cv::MatND getHistogram(const cv::Mat &image){
    		cv::MatND hist;
    		cv::calcHist(&image, 1, channels, cv::Mat(), hist, 1, histSize, ranges);
    		return hist;
    	}
    	cv::Mat getHistogramImage(const cv::Mat &image){
    		cv::MatND hist = getHistogram(image);
    		double maxVal = 0;
    		double minVal = 0;
    		cv::minMaxLoc(hist, &minVal, &maxVal, 0, 0);
    		cv::Mat histImg(histSize[0], histSize[0], CV_8U, cv::Scalar(255));
    		int hpt = static_cast<int>(0.9*histSize[0]);
    		for (int h = 0; h < histSize[0]; h++){
    			float binVal = hist.at<float>(h);
    			int intensity = static_cast<int>(binVal*hpt / maxVal);
    			cv::line(histImg, cv::Point(h, histSize[0]), cv::Point(h, histSize[0] - intensity), cv::Scalar::all(100), 1);
    		}
    		return histImg;
    	}
    };
    
    /*
    **define a struct included intrinsic and extrinsic args
    */
    typedef struct {
    	double m_K[3][3]; // 3x3 intrinsic matrix
    	double m_RotMatrix[3][3]; // rotation matrix
    	double m_Trans[3]; // translation vector
    
    	double m_ProjMatrix[4][4]; // projection matrix
    } CalibStruct;
    /*
    **define globle variables
    */
    CalibStruct m_CalibParams[8];
    int m_NumCameras = 8;
    int m_Width = 1024, m_Height = 768; // camera resolution is 1024x768
    double pts[8][3];
    
    
    /*
    **declare function
    */
    void InitializeFromFile(char *fileName);
    double DepthLevelToZ(unsigned char d);
    unsigned char ZToDepthLever(double z);
    double projXYZtoUV(double projMatrix[4][4], double x, double y, double z, double *u, double *v);
    void projUVZtoXY(double projMatrix[4][4], double u, double v, double z, double *x, double *y, double pt[8][2]);
    void wrapingImage(int ref, int proj, cv::Mat &imageColor, cv::Mat &imageDepth, cv::Mat &imageColorOut);
    void pointProject_from_ref_to_otherView(double pts[8][2], int ref, int u, int v, unsigned char d);
    /*
    **define function
    */
    
    /*
    ** read text file and write args to struct of globle variable
    */
    void readCalibrationFile(char *fileName)
    {
    	int i, j, k;
    	FILE *pIn;
    	double dIn; // dummy variable
    	int camIdx;
    
    	if (pIn = fopen(fileName, "r"))
    	{
    		for (k = 0; k<m_NumCameras; k++)
    		{
    			// camera index
    			fscanf(pIn, "%d", &camIdx);
    			//std::cout << camIdx << std::endl;
    
    			// camera intrinsics
    			for (i = 0; i < 3; i++){
    				fscanf(pIn, "%lf\t%lf\t%lf", &(m_CalibParams[camIdx].m_K[i][0]), &(m_CalibParams[camIdx].m_K[i][1]), &(m_CalibParams[camIdx].m_K[i][2]));
    				//std::cout << (m_CalibParams[camIdx].m_K[i][0])<<"\t"<<(m_CalibParams[camIdx].m_K[i][1]) <<"\t"<< (m_CalibParams[camIdx].m_K[i][2]) << std::endl;
    			}
    
    			// read barrel distortion params (assume 0)
    			fscanf(pIn, "%lf", &dIn);
    			fscanf(pIn, "%lf", &dIn);
    
    			// read extrinsics
    			for (i = 0; i<3; i++)
    			{
    				for (j = 0; j<3; j++)
    				{
    					fscanf(pIn, "%lf", &dIn);
    					m_CalibParams[camIdx].m_RotMatrix[i][j] = dIn;
    					//std::cout << m_CalibParams[camIdx].m_RotMatrix[i][j] << std::endl;
    				}
    
    				fscanf(pIn, "%lf", &dIn);
    				m_CalibParams[camIdx].m_Trans[i] = dIn;
    			}
    
    		}
    
    		fclose(pIn);
    	}
    }// readCalibrationFile
    
    /*
    **calcular all projectionMatrices depended on struct variables
    */
    void computeProjectionMatrices()
    {
    	int i, j, k, camIdx;
    	double(*inMat)[3];
    	double exMat[3][4];
    
    	for (camIdx = 0; camIdx<m_NumCameras; camIdx++)
    	{
    		// The intrinsic matrix
    		inMat = m_CalibParams[camIdx].m_K;
    
    		// The extrinsic matrix
    		for (i = 0; i<3; i++)
    		{
    			for (j = 0; j<3; j++)
    			{
    				exMat[i][j] = m_CalibParams[camIdx].m_RotMatrix[i][j];
    			}
    		}
    
    		for (i = 0; i<3; i++)
    		{
    			exMat[i][3] = m_CalibParams[camIdx].m_Trans[i];
    		}
    
    		// Multiply the intrinsic matrix by the extrinsic matrix to find our projection matrix
    		for (i = 0; i<3; i++)
    		{
    			for (j = 0; j<4; j++)
    			{
    				m_CalibParams[camIdx].m_ProjMatrix[i][j] = 0.0;
    
    				for (k = 0; k<3; k++)
    				{
    					m_CalibParams[camIdx].m_ProjMatrix[i][j] += inMat[i][k] * exMat[k][j];
    				}
    			}
    		}
    
    		m_CalibParams[camIdx].m_ProjMatrix[3][0] = 0.0;
    		m_CalibParams[camIdx].m_ProjMatrix[3][1] = 0.0;
    		m_CalibParams[camIdx].m_ProjMatrix[3][2] = 0.0;
    		m_CalibParams[camIdx].m_ProjMatrix[3][3] = 1.0;
    	}
    }
    
    /**
    **init projection matrix
    */
    void InitializeFromFile(char *fileName)
    {
    	readCalibrationFile(fileName);
    	computeProjectionMatrices();
    }
    /**
    **calcular z depended on d of depth image
    */
    double DepthLevelToZ(unsigned char d)
    {
    	double z;
    	double MinZ = 44.0, MaxZ = 120.0;
    
    	z = 1.0 / ((d / 255.0)*(1.0 / MinZ - 1.0 / MaxZ) + 1.0 / MaxZ);
    	return z;
    }
    
    /**
    **calcular d of depth image depended on z
    */
    unsigned char ZToDepthLever(double z)
    {
    	double MinZ = 44.0, MaxZ = 120.0;
    	unsigned char d;
    	d = (unsigned char)(255.0*(1 / (double)z - 1 / MaxZ) / (1 / MinZ - 1 / MaxZ));
    	return d;
    }
    
    /**
    **calcular x,y depended on u,v,z and projection Matrix
    **for example,projection Matrix is m_CalibParams[i].m_ProjMatrix which is index of camera
    */
    void projUVZtoXY(double projMatrix[4][4], double u, double v, double z, double *x, double *y)
    {
    	double c0, c1, c2;
    
    	// image (0,0) is bottom lefthand corner
    	v = (double)m_Height - v - 1.0;
    
    	c0 = z*projMatrix[0][2] + projMatrix[0][3];
    	c1 = z*projMatrix[1][2] + projMatrix[1][3];
    	c2 = z*projMatrix[2][2] + projMatrix[2][3];
    
    	*y = u*(c1*projMatrix[2][0] - projMatrix[1][0] * c2) +
    		v*(c2*projMatrix[0][0] - projMatrix[2][0] * c0) +
    		projMatrix[1][0] * c0 - c1*projMatrix[0][0];
    
    	*y /= v*(projMatrix[2][0] * projMatrix[0][1] - projMatrix[2][1] * projMatrix[0][0]) +
    		u*(projMatrix[1][0] * projMatrix[2][1] - projMatrix[1][1] * projMatrix[2][0]) +
    		projMatrix[0][0] * projMatrix[1][1] - projMatrix[1][0] * projMatrix[0][1];
    
    	*x = (*y)*(projMatrix[0][1] - projMatrix[2][1] * u) + c0 - c2*u;
    	*x /= projMatrix[2][0] * u - projMatrix[0][0];
    } // projUVZtoXY
    
    /**
    **calcular u,v,z1 depended on x,y,z
    **z1 is after projection and z is before projection.z1 is return value
    **/
    
    double projXYZtoUV(double projMatrix[4][4], double x, double y, double z, double *u, double *v)
    {
    	double w;
    
    	*u = projMatrix[0][0] * x +
    		projMatrix[0][1] * y +
    		projMatrix[0][2] * z +
    		projMatrix[0][3];
    
    	*v = projMatrix[1][0] * x +
    		projMatrix[1][1] * y +
    		projMatrix[1][2] * z +
    		projMatrix[1][3];
    
    	w = projMatrix[2][0] * x +
    		projMatrix[2][1] * y +
    		projMatrix[2][2] * z +
    		projMatrix[2][3];
    
    	*u /= w;
    	*v /= w;
    
    	// image (0,0) is bottom lefthand corner
    	*v = (double)m_Height - *v - 1.0;
    
    	return w;
    
    } // projXYZtoUV
    
    /**
    
    **/
    
    void pointProject_from_ref_to_otherView(double pts[8][3], int ref, int u, int v, unsigned char d)
    {
    	double x, y, z = DepthLevelToZ(d);
    
    	//printf("Testing projection of pt (%d,%d) in camera 0 with d = %d (z = %f) to other cameras\n", u, v, d, z);
    
    	projUVZtoXY(m_CalibParams[ref].m_ProjMatrix, (double)u, (double)v, z, &x, &y);
    	//printf("3D pt = (%f, %f, %f) [coordinates wrt reference camera]\n", x, y, z);
    
    	for (int cam = 0; cam<8; cam++)
    	{
    		double *pt = pts[cam];
    
    		pt[2]=projXYZtoUV(m_CalibParams[cam].m_ProjMatrix, x, y, z, &pt[0], &pt[1]);
    		//printf("Camera %d: (%f, %f)\n", cam, pt[0], pt[1]);
    		pt[2] = ZToDepthLever(pt[2]);
    	}
    }
    
    /**
    **wraping image,ref represent reference cam,proj represent projection cam
    **the kernal code
    **/
    void wrapingImage(int ref, int proj, cv::Mat &imageColor, cv::Mat &imageDepth, cv::Mat &imageColorOut, cv::Mat &imageDepthOut)
    {
    	for (int v = 0; v < imageColor.rows; v++)
    		for (int u = 0; u < imageColor.cols; u++)
    		{
    			double d = imageDepth.at<cv::Vec3b>(v, u)[0];
    			pointProject_from_ref_to_otherView(pts, ref, u, v, d);
    			int u1 = (int)pts[proj][0];
    			int v1 = (int)pts[proj][1];
    			int k1 = (int)pts[proj][2];
    			if (u1 < 0 || u1 >= imageColor.cols - 1 || v1 < 0 || v1 >= imageColor.rows - 1)
    				continue;
    			if (k1 < imageDepthOut.at<cv::Vec3b>(v1, u1)[0])
    				continue;
    			imageColorOut.at<cv::Vec3b>(v1, u1) = imageColor.at<cv::Vec3b>(v, u);
    			imageDepthOut.at<cv::Vec3b>(v1, u1)[0] = k1;
    			imageDepthOut.at<cv::Vec3b>(v1, u1)[1] = k1;
    			imageDepthOut.at<cv::Vec3b>(v1, u1)[2] = k1;
    		}
    }
    
    void dipslay(char *calibParam, char *refColor, char *refDepth, char *refColor2, char *refDepth2, char *actColor)
    {
    	//initialize projection_Matrix
    	InitializeFromFile(calibParam);
    	//display projection_Matrix
    	for (int i = 0; i < m_NumCameras; i++){
    		for (int j = 0; j < 3; j++){
    			for (int k = 0; k < 3; k++)
    				std::cout << m_CalibParams[i].m_K[j][k] << "\t";
    			std::cout << std::endl;
    		}
    
    		for (int j = 0; j < 3; j++){
    			for (int k = 0; k < 3; k++)
    				std::cout << m_CalibParams[i].m_RotMatrix[j][k] << "\t";
    			std::cout << std::endl;
    		}
    		for (int k = 0; k < 3; k++)
    			std::cout << m_CalibParams[i].m_Trans[k] << "\t";
    		std::cout << std::endl;
    		std::cout << std::endl;
    		std::cout << std::endl;
    		std::cout << std::endl;
    	}
    	//suspend and users enter a digit
    	int aa;
    	std::cin >> aa;
    	//read color image and depth image of refrence
    	cv::Mat imageColor = cv::imread(refColor);
    	cv::Mat imageDepth = cv::imread(refDepth);
    	cv::Mat imageColor2 = cv::imread(refColor2);
    	cv::Mat imageDepth2 = cv::imread(refDepth2);
    	//read true image used to compare
    	cv::Mat imageColor_actual = cv::imread(actColor);
    	//set reference cam
    	int ref = 0;
    	int ref2 = 2;
    	//set projection cam
    	int proj = 1;
    	//test code
    	pointProject_from_ref_to_otherView(pts, ref, 700, 700, imageDepth.at<cv::Vec3b>(700, 700)[0]);
    	for (int i = 0; i < 8; i++)
    	{
    		std::cout << pts[i][0] << "\t" << pts[i][1] << std::endl;
    	}
    	std::cin >> aa;
    	//define two variable of output
    	cv::Mat imageColorOut;
    	cv::Mat imageColorOut2;
    	cv::Mat imageDepthOut;
    	imageColorOut.create(imageColor.rows, imageColor.cols, imageColor.type());
    	imageColorOut2.create(imageColor.rows, imageColor.cols, imageColor.type());
    	imageDepthOut.create(imageColor.rows, imageColor.cols, imageColor.type());
    	for (int v = 0; v < imageColor.rows; v++)
    	{
    		for (int u = 0; u < imageColor.cols; u++)
    		{
    			imageColorOut.at<cv::Vec3b>(v, u)[0] = 0;
    			imageColorOut.at<cv::Vec3b>(v, u)[1] = 0;
    			imageColorOut2.at<cv::Vec3b>(v, u)[2] = 0;
    			imageColorOut2.at<cv::Vec3b>(v, u)[0] = 0;
    			imageColorOut2.at<cv::Vec3b>(v, u)[1] = 0;
    			imageColorOut.at<cv::Vec3b>(v, u)[2] = 0;
    			imageDepthOut.at<cv::Vec3b>(v, u)[0] = 0;
    			imageDepthOut.at<cv::Vec3b>(v, u)[1] = 0;
    			imageDepthOut.at<cv::Vec3b>(v, u)[2] = 0;
    		
    		}
    	}
    	//save_dir
    	char *save_dir = "C:\\Users\\jiang\\Desktop\\experientdata\\experiencePictrue\\";
    	//wraping from reference view to virtruel view 
    	wrapingImage(ref, proj, imageColor, imageDepth, imageColorOut,imageDepthOut);
    	wrapingImage(ref2, proj, imageColor2, imageDepth2, imageColorOut, imageDepthOut);
    	//display reference_image
    	/*cv::imshow("reference_image", imageColor);
    	cv::imwrite("C:\\Users\\jiang\\Desktop\\experientdata\\experiencePictrue\\reference_image.jpg", imageColor);*/
    	//display virtruel_image
    	cv::medianBlur(imageColorOut, imageColorOut, 3);
    	cv::imshow("virtruel_Color_image01", imageColorOut);
    	cv::imwrite("C:\\Users\\jiang\\Desktop\\experientdata\\experiencePictrue\\virtruel_Color_image01.jpg", imageColorOut);
    	display virtruel_image
    	//cv::imshow("virtruel_Color_image21", imageColorOut2);
    	//cv::imwrite("C:\\Users\\jiang\\Desktop\\experientdata\\experiencePictrue\\virtruel_Color_image21.jpg", imageColorOut2);
    	//display virtruel_image
    	cv::medianBlur(imageDepthOut, imageDepthOut, 3);
    	cv::imshow("virtruel_Depth_image", imageDepthOut);
    	cv::imwrite("C:\\Users\\jiang\\Desktop\\experientdata\\experiencePictrue\\virtruel_Depth_image.jpg", imageDepthOut);
    	//display actruel_image
    	cv::imshow("actruel_image", imageColor_actual);
    	cv::imwrite("C:\\Users\\jiang\\Desktop\\experientdata\\experiencePictrue\\actruel_image.jpg", imageColor_actual);
    	mix reference and virtruel and check changes
    	//cv::Mat imageColorRefVSProj;
    	//cv::addWeighted(imageColor, 0.5, imageColorOut, 0.5, 0.0, imageColorRefVSProj);
    	//cv::imshow("imageColorRefVSProj", imageColorRefVSProj);
    	//cv::imwrite("C:\\Users\\jiang\\Desktop\\experientdata\\experiencePictrue\\imageColorRefVSProj.jpg", imageColorRefVSProj);
    	mix actual and virtruel and check changes
    	//cv::Mat imageColorActVSProj;
    	//cv::addWeighted(imageColor_actual, 0.5, imageColorOut, 0.5, 0.0, imageColorActVSProj);
    	//cv::imshow("imageColorActVSProj", imageColorActVSProj);
    	//cv::imwrite("C:\\Users\\jiang\\Desktop\\experientdata\\experiencePictrue\\imageColorActVSProj.jpg", imageColorActVSProj);
    	cv::waitKey();
    
    }
    
    void main()
    {
    	char *refColor = "C:\\Users\\jiang\\Desktop\\experientdata\\3DVideos-distrib\\MSR3DVideo-Breakdancers\\cam0\\color-cam0-f000.jpg";
    	char *refDepth = "C:\\Users\\jiang\\Desktop\\experientdata\\3DVideos-distrib\\MSR3DVideo-Breakdancers\\cam0\\depth-cam0-f000.png";
    	char *refColor2 = "C:\\Users\\jiang\\Desktop\\experientdata\\3DVideos-distrib\\MSR3DVideo-Breakdancers\\cam2\\color-cam2-f000.jpg";
    	char *refDepth2 = "C:\\Users\\jiang\\Desktop\\experientdata\\3DVideos-distrib\\MSR3DVideo-Breakdancers\\cam2\\depth-cam2-f000.png";
    	char *calibParam = "C:\\Users\\jiang\\Desktop\\experientdata\\3DVideos-distrib\\MSR3DVideo-Breakdancers\\calibParams-breakdancers.txt";
    	char *actColor = "C:\\Users\\jiang\\Desktop\\experientdata\\3DVideos-distrib\\MSR3DVideo-Breakdancers\\cam1\\color-cam1-f000.jpg";
    	dipslay(calibParam, refColor, refDepth, refColor2, refDepth2, actColor);
    }
    #endif

[http_research.microsoft.com_en-us_downloads_5e4675af-03f4-4b16-b3bc-a85c5bafb21d]: http://research.microsoft.com/en-us/downloads/5e4675af-03f4-4b16-b3bc-a85c5bafb21d/
[Center]: /images/20220805/48862cd6fe2e403d90a7ce13a6308402.png
[Center 1]: /images/20220805/2bbf764b3cbe40e783b100f2c046df0e.png