EmguCV學習——簡單算法差分與高斯

2019-11-14 14:06:40

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公司項目需要檢測運動物體，我對opencv也沒啥研究，google了好久看了好多方法，最簡單的就是差分與高斯背景建模了。

旁邊搞c++的同事正在搞更nb的算法，等出來了我再轉成C#版的分享。

先看差分

 1             //移動窗口        
　　　　　　[System.Runtime.InteropServices.DllImportAttribute("opencv_highgui2410.dll", EntryPoint = "cvMoveWindow")] 2         public static extern void cvMoveWindow([System.Runtime.InteropServices.InAttribute()] [System.Runtime.InteropServices.MarshalAsAttribute(System.Runtime.InteropServices.UnmanagedType.LPStr)] string name, int x, int y); 3         //代表x幀差分，可以自由更改 4         static int USE_N_FRAMES_DIFF = 10; 5  6         public void PicDiff(string videoPath) 7         { 8             int iFrameIndex = 0; 9 10             IntPtr piplGrayImg = IntPtr.Zero;11 12             IntPtr[] pIplFrameDiff = new IntPtr[USE_N_FRAMES_DIFF - 1];13 14             IntPtr[] pIplFrame = new IntPtr[USE_N_FRAMES_DIFF];15 16             IntPtr CatchFrame = CvInvoke.cvCreateFileCapture(videoPath);17             // 得到總幀數18             var count = CvInvoke.cvGetCapturePRoperty(CatchFrame, Emgu.CV.CvEnum.CAP_PROP.CV_CAP_PROP_FRAME_COUNT);19             // 視頻寬度20             int wd = (int)CvInvoke.cvGetCaptureProperty(CatchFrame, Emgu.CV.CvEnum.CAP_PROP.CV_CAP_PROP_FRAME_WIDTH);21             // 視頻高度22             int hg = (int)CvInvoke.cvGetCaptureProperty(CatchFrame, Emgu.CV.CvEnum.CAP_PROP.CV_CAP_PROP_FRAME_HEIGHT);23             //// 當前幀位置24             //CvInvoke.cvGetCaptureProperty(CatchFrame, Emgu.CV.CvEnum.CAP_PROP.CV_CAP_PROP_POS_FRAMES);25             //// 幀頻26             CvInvoke.cvGetCaptureProperty(CatchFrame, Emgu.CV.CvEnum.CAP_PROP.CV_CAP_PROP_FPS);27 28             CvInvoke.cvNamedWindow("source");29             CvInvoke.cvNamedWindow("Out");30             cvMoveWindow("source", 0, 0);31             cvMoveWindow("Out", 0, 350);32             IntPtr FrameImg;33 34             IntPtr rawImage = IntPtr.Zero;35             rawImage = CvInvoke.cvCreateImage(new Size(wd, hg), Emgu.CV.CvEnum.IPL_DEPTH.IPL_DEPTH_8U, 1);36             IntPtr pIplFrameDiffOr = IntPtr.Zero;37             IntPtr pIplFrameDiffOrCC = IntPtr.Zero;38             IntPtr pIplFrameSmooth = IntPtr.Zero;39             pIplFrameDiffOr = CvInvoke.cvCreateImage(new Size(wd, hg), Emgu.CV.CvEnum.IPL_DEPTH.IPL_DEPTH_8U, 1);40             pIplFrameDiffOrCC = CvInvoke.cvCreateImage(new Size(wd, hg), Emgu.CV.CvEnum.IPL_DEPTH.IPL_DEPTH_8U, 1);41             pIplFrameSmooth = CvInvoke.cvCreateImage(new Size(wd, hg), Emgu.CV.CvEnum.IPL_DEPTH.IPL_DEPTH_8U, 1);42 43             while ((FrameImg = CvInvoke.cvQueryFrame(CatchFrame)) != IntPtr.Zero)44             {45                46                 Rectangle cr = CvInvoke.cvGetImageROI(FrameImg);47 48                 pIplGrayImg = CvInvoke.cvCreateImage(cr.Size, Emgu.CV.CvEnum.IPL_DEPTH.IPL_DEPTH_8U, 1);49                 50                 CvInvoke.cvCvtColor(FrameImg, pIplGrayImg, Emgu.CV.CvEnum.COLOR_CONVERSION.BGR2GRAY);51 52                 CvInvoke.cvSaveImage(savename, pIplGrayImg, IntPtr.Zero);53                 pIplFrame[iFrameIndex % USE_N_FRAMES_DIFF] = pIplGrayImg;54 55                 if (iFrameIndex >= USE_N_FRAMES_DIFF - 1)56                 {57                     for (int i = 0; i < USE_N_FRAMES_DIFF - 1; i++)58                     {59 60                         CvInvoke.cvAbsDiff(pIplFrame[i], pIplFrame[i + 1], rawImage);61                         pIplFrameDiff[i] = rawImage;62                         CvInvoke.cvThreshold(pIplFrameDiff[i], pIplFrameDiff[i], 20, 255, Emgu.CV.CvEnum.THRESH.CV_THRESH_BINARY);63 　　　　　　　　　　　　　　//上面第三個參數為設置的閥值以此來根據物體運動時前后幀的差異產生白點64                     }65 66                     for (int i = 0; i < USE_N_FRAMES_DIFF - 2; i++)67                     {68                         CvInvoke.cvOr(pIplFrameDiff[i], pIplFrameDiff[i + 1], pIplFrameDiffOr, IntPtr.Zero);69 70                         if (i + 1 < USE_N_FRAMES_DIFF - 2)71                         {72                             CvInvoke.cvCopy(pIplFrameDiffOr, pIplFrameDiff[i + 1], IntPtr.Zero);73                         }74 75                     }76                 }77                 78 79                 CvInvoke.cvShowImage("source", FrameImg);80                 CvInvoke.cvShowImage("Out", pIplFrameDiffOr);81                82                 CvInvoke.cvWaitKey(1);83                 iFrameIndex++;84 85             } 86 }

程序運行結果如圖所示

高斯背景建模

 1      public void guassModel(string videoPath) 2       {    3             int iFrameIndex = 0; 4             IntPtr CatchFrame = CvInvoke.cvCreateFileCapture(videoPath); 5             // 得到總幀數 6             var count = CvInvoke.cvGetCaptureProperty(CatchFrame, Emgu.CV.CvEnum.CAP_PROP.CV_CAP_PROP_FRAME_COUNT); 7             // 視頻寬度 8             int wd = (int)CvInvoke.cvGetCaptureProperty(CatchFrame, Emgu.CV.CvEnum.CAP_PROP.CV_CAP_PROP_FRAME_WIDTH); 9             // 視頻高度10             int hg = (int)CvInvoke.cvGetCaptureProperty(CatchFrame, Emgu.CV.CvEnum.CAP_PROP.CV_CAP_PROP_FRAME_HEIGHT);11             //// 幀頻12             CvInvoke.cvGetCaptureProperty(CatchFrame, Emgu.CV.CvEnum.CAP_PROP.CV_CAP_PROP_FPS);13             IntPtr background = CvInvoke.cvCreateImage(new Size(wd, hg), Emgu.CV.CvEnum.IPL_DEPTH.IPL_DEPTH_8U, 1);14             IntPtr foreground = CvInvoke.cvCreateImage(new Size(wd, hg), Emgu.CV.CvEnum.IPL_DEPTH.IPL_DEPTH_8U, 1);15 16             IntPtr FrameImg;17             Emgu.CV.VideoSurveillance.BGStatModel<Bgr> bg = null;18             CvInvoke.cvNamedWindow("bg");19             CvInvoke.cvNamedWindow("fg");20             CvInvoke.cvNamedWindow("source");21             cvMoveWindow("bg", 400, 0);22             cvMoveWindow("gf", 800, 0);23             cvMoveWindow("source", 0, 0);24             while ((FrameImg = CvInvoke.cvQueryFrame(CatchFrame)) != IntPtr.Zero)25             {26                 Image<Bgr, byte> FramePic = new Image<Bgr, byte>(wd, hg);27                 CvInvoke.cvCopy(FrameImg, FramePic, IntPtr.Zero);28                 iFrameIndex++;29                 if (iFrameIndex == 1)30                 {31                     //高斯背景建模參數32                     Emgu.CV.Structure.MCvGaussBGStatModelParams pstruct = new MCvGaussBGStatModelParams();33                     pstruct.win_size = 50;34                     pstruct.n_gauss = 3;35                     pstruct.bg_threshold = 0.7;36                     pstruct.std_threshold = 3.5;37                     pstruct.minArea = 100; 38                     pstruct.weight_init = 0.333;39                     pstruct.variance_init = 30;40                     bg = new Emgu.CV.VideoSurveillance.BGStatModel<Bgr>(FramePic, ref pstruct);41                 }42                 else43                 {44                     CvInvoke.cvShowImage("source", FrameImg);45                     CvInvoke.cvWaitKey(10);46                     //更新47                     bg.Update(FramePic);48                     background = bg.BackgroundMask;49                     CvInvoke.cvShowImage("bg", background);50                     CvInvoke.cvWaitKey(10);51                     foreground = bg.ForegroundMask;52                     CvInvoke.cvShowImage("fg", foreground);53                     CvInvoke.cvWaitKey(10);54                 }55             }56             CvInvoke.cvDestroyWindow("source");57             CvInvoke.cvDestroyWindow("bg");58             CvInvoke.cvDestroyWindow("fg");59         }