OpenCV-Python Tutorials

【实例简介】OpenCV-Python Tutorials

【实例截图】

【核心代码】

目录

OpenCV  PAGEREF _Toc96704818 \h 3

OpenCV-Python  PAGEREF _Toc96704819 \h 3

OpenCV-Python Tutorials  PAGEREF _Toc96704820 \h 4

OpenCV Needs You !!!  PAGEREF _Toc96704821 \h 4

Contributors  PAGEREF _Toc96704822 \h 4

Additional Resources  PAGEREF _Toc96704823 \h 5

Goals  PAGEREF _Toc96704824 \h 5

Installing OpenCV from prebuilt binaries  PAGEREF _Toc96704825 \h 5

Building OpenCV from source  PAGEREF _Toc96704826 \h 6

Additional Resources  PAGEREF _Toc96704827 \h 11

Exercises  PAGEREF _Toc96704828 \h 11

Goals  PAGEREF _Toc96704829 \h 11

Introduction  PAGEREF _Toc96704830 \h 11

Installing OpenCV-Python from Pre-built Binaries  PAGEREF _Toc96704831 \h 11

Installing OpenCV from source  PAGEREF _Toc96704832 \h 12

Compulsory Dependencies  PAGEREF _Toc96704833 \h 12

Optional Dependencies  PAGEREF _Toc96704834 \h 13

Downloading OpenCV  PAGEREF _Toc96704835 \h 13

Configuring and Installing  PAGEREF _Toc96704836 \h 14

Additional Resources  PAGEREF _Toc96704837 \h 17

Exercises  PAGEREF _Toc96704838 \h 17

Goals  PAGEREF _Toc96704839 \h 17

Installing OpenCV-Python from Pre-built Binaries  PAGEREF _Toc96704840 \h 18

Building OpenCV from source  PAGEREF _Toc96704841 \h 18

Required build dependencies  PAGEREF _Toc96704842 \h 19

Optional Dependencies  PAGEREF _Toc96704843 \h 19

Downloading OpenCV  PAGEREF _Toc96704844 \h 20

Configuring and Installing  PAGEREF _Toc96704845 \h 20

Goal  PAGEREF _Toc96704846 \h 22

Source Code  C Python  PAGEREF _Toc96704847 \h 22

Explanation  C Python  PAGEREF _Toc96704848 \h 23

Goal  PAGEREF _Toc96704849 \h 24

Capture Video from Camera  PAGEREF _Toc96704850 \h 24

Playing Video from file  PAGEREF _Toc96704851 \h 26

Saving a Video  PAGEREF _Toc96704852 \h 26

Additional Resources  PAGEREF _Toc96704853 \h 27

Exercises  PAGEREF _Toc96704854 \h 28

Goal  PAGEREF _Toc96704855 \h 28

Code  PAGEREF _Toc96704856 \h 28

Drawing Line  PAGEREF _Toc96704857 \h 28

Drawing Rectangle  PAGEREF _Toc96704858 \h 28

Drawing Circle  PAGEREF _Toc96704859 \h 29

Drawing Ellipse  PAGEREF _Toc96704860 \h 29

Drawing Polygon  PAGEREF _Toc96704861 \h 29

Adding Text to Images:  PAGEREF _Toc96704862 \h 29

Result  PAGEREF _Toc96704863 \h 30

Additional Resources  PAGEREF _Toc96704864 \h 30

Exercises  PAGEREF _Toc96704865 \h 31

Goal  PAGEREF _Toc96704866 \h 31

Simple Demo  PAGEREF _Toc96704867 \h 31

More Advanced Demo  PAGEREF _Toc96704868 \h 32

Additional Resources  PAGEREF _Toc96704869 \h 33

Exercises  PAGEREF _Toc96704870 \h 33

Goal  PAGEREF _Toc96704871 \h 33

Code Demo  PAGEREF _Toc96704872 \h 33

Exercises  PAGEREF _Toc96704873 \h 35

Goal  PAGEREF _Toc96704874 \h 36

Accessing and Modifying pixel values  PAGEREF _Toc96704875 \h 36

Accessing Image Properties  PAGEREF _Toc96704876 \h 37

Image ROI  PAGEREF _Toc96704877 \h 38

Splitting and Merging Image Channels  PAGEREF _Toc96704878 \h 39

Making Borders for Images (Padding)  PAGEREF _Toc96704879 \h 39

Additional Resources  PAGEREF _Toc96704880 \h 41

Exercises  PAGEREF _Toc96704881 \h 41

Goal  PAGEREF _Toc96704882 \h 41

Image Addition  PAGEREF _Toc96704883 \h 41

Image Blending  PAGEREF _Toc96704884 \h 42

Bitwise Operations  PAGEREF _Toc96704885 \h 43

Additional Resources  PAGEREF _Toc96704886 \h 44

Exercises  PAGEREF _Toc96704887 \h 44

Goal  PAGEREF _Toc96704888 \h 44

Measuring Performance with OpenCV  PAGEREF _Toc96704889 \h 45

Default Optimization in OpenCV  PAGEREF _Toc96704890 \h 45

Measuring Performance in IPython  PAGEREF _Toc96704891 \h 46

More IPython magic commands  PAGEREF _Toc96704892 \h 47

Performance Optimization Techniques  PAGEREF _Toc96704893 \h 47

Additional Resources  PAGEREF _Toc96704894 \h 48

Exercises  PAGEREF _Toc96704895 \h 48

Goal  PAGEREF _Toc96704896 \h 49

Changing Color-space  PAGEREF _Toc96704897 \h 49

Object Tracking  PAGEREF _Toc96704898 \h 49

How to find HSV values to track?  PAGEREF _Toc96704899 \h 51

Additional Resources  PAGEREF _Toc96704900 \h 51

Exercises  PAGEREF _Toc96704901 \h 51

Goals  PAGEREF _Toc96704902 \h 51

Transformations  PAGEREF _Toc96704903 \h 51

Scaling  PAGEREF _Toc96704904 \h 52

Translation  PAGEREF _Toc96704905 \h 52

Rotation  PAGEREF _Toc96704906 \h 53

Affine Transformation  PAGEREF _Toc96704907 \h 54

Perspective Transformation  PAGEREF _Toc96704908 \h 54

Additional Resources  PAGEREF _Toc96704909 \h 55

Exercises  PAGEREF _Toc96704910 \h 55

Goal  PAGEREF _Toc96704911 \h 56

Simple Thresholding  PAGEREF _Toc96704912 \h 56

Adaptive Thresholding  PAGEREF _Toc96704913 \h 57

Otsu's Binarization  PAGEREF _Toc96704914 \h 59

How does Otsu's Binarization work?  PAGEREF _Toc96704915 \h 61

Additional Resources  PAGEREF _Toc96704916 \h 62

Exercises  PAGEREF _Toc96704917 \h 62

Goals  PAGEREF _Toc96704918 \h 62

2D Convolution ( Image Filtering )  PAGEREF _Toc96704919 \h 63

Image Blurring (Image Smoothing)  PAGEREF _Toc96704920 \h 64

4.4.1 Averaging  PAGEREF _Toc96704921 \h 64

4.4.2 Gaussian Blurring  PAGEREF _Toc96704922 \h 65

4.4.3 Median Blurring  PAGEREF _Toc96704923 \h 66

4.4.4 Bilateral Filtering  PAGEREF _Toc96704924 \h 67

Additional Resources  PAGEREF _Toc96704925 \h 68

Exercises  PAGEREF _Toc96704926 \h 68

Goal  PAGEREF _Toc96704927 \h 68

Theory  PAGEREF _Toc96704928 \h 68

4.5.1 Erosion  PAGEREF _Toc96704929 \h 69

4.5.2 Dilation  PAGEREF _Toc96704930 \h 69

4.5.3 Opening  PAGEREF _Toc96704931 \h 70

4.5.4 Closing  PAGEREF _Toc96704932 \h 70

4.5.5 Morphological Gradient  PAGEREF _Toc96704933 \h 71

4.5.6 Top Hat  PAGEREF _Toc96704934 \h 71

4.5.7 Black Hat  PAGEREF _Toc96704935 \h 72

Structuring Element  PAGEREF _Toc96704936 \h 72

Additional Resources  PAGEREF _Toc96704937 \h 73

Exercises  PAGEREF _Toc96704938 \h 73

Goal  PAGEREF _Toc96704939 \h 73

Theory  PAGEREF _Toc96704940 \h 73

4.6.1 Sobel and Scharr Derivatives  PAGEREF _Toc96704941 \h 73

4.6.2 Laplacian Derivatives  PAGEREF _Toc96704942 \h 74

Code  PAGEREF _Toc96704943 \h 74

One Important Matter!  PAGEREF _Toc96704944 \h 75

Additional Resources  PAGEREF _Toc96704945 \h 76

Exercises  PAGEREF _Toc96704946 \h 76

Goal  PAGEREF _Toc96704947 \h 76

Theory  PAGEREF _Toc96704948 \h 77

Canny Edge Detection in OpenCV  PAGEREF _Toc96704949 \h 79

Additional Resources  PAGEREF _Toc96704950 \h 80

Exercises  PAGEREF _Toc96704951 \h 80

Goal  PAGEREF _Toc96704952 \h 80

Theory  PAGEREF _Toc96704953 \h 80

Image Blending using Pyramids  PAGEREF _Toc96704954 \h 83

Additional Resources  PAGEREF _Toc96704955 \h 85

Exercises  PAGEREF _Toc96704956 \h 85

Goal  PAGEREF _Toc96704957 \h 86

What are contours?  PAGEREF _Toc96704958 \h 86

How to draw the contours?  PAGEREF _Toc96704959 \h 87

Contour Approximation Method  PAGEREF _Toc96704960 \h 88

Additional Resources  PAGEREF _Toc96704961 \h 88

Exercises  PAGEREF _Toc96704962 \h 89

Goal  PAGEREF _Toc96704963 \h 89

4.9.2.1 Moments  PAGEREF _Toc96704964 \h 89

4.9.2.2 Contour Area  PAGEREF _Toc96704965 \h 90

4.9.2.3 Contour Perimeter  PAGEREF _Toc96704966 \h 90

4.9.2.4 Contour Approximation  PAGEREF _Toc96704967 \h 90

4.9.2.5 Convex Hull  PAGEREF _Toc96704968 \h 91

4.9.2.6 Checking Convexity  PAGEREF _Toc96704969 \h 92

4.9.2.7 Bounding Rectangle  PAGEREF _Toc96704970 \h 92

4.9.2.7.a. Straight Bounding Rectangle  PAGEREF _Toc96704971 \h 92

4.9.2.7.b. Rotated Rectangle  PAGEREF _Toc96704972 \h 92

4.9.2.8 Minimum Enclosing Circle  PAGEREF _Toc96704973 \h 93

4.9.2.9 Fitting an Ellipse  PAGEREF _Toc96704974 \h 94

4.9.2.10 Fitting a Line  PAGEREF _Toc96704975 \h 94

Additional Resources  PAGEREF _Toc96704976 \h 95

Exercises  PAGEREF _Toc96704977 \h 95

4.9.3.1 Aspect Ratio  PAGEREF _Toc96704978 \h 95

4.9.3.2 Extent  PAGEREF _Toc96704979 \h 96

4.9.3.3 Solidity  PAGEREF _Toc96704980 \h 96

4.9.3.4 Equivalent Diameter  PAGEREF _Toc96704981 \h 96

4.9.3.5 Orientation  PAGEREF _Toc96704982 \h 96

4.9.3.6 Mask and Pixel Points  PAGEREF _Toc96704983 \h 97

4.9.3.7 Maximum Value, Minimum Value and their locations  PAGEREF _Toc96704984 \h 97

4.9.3.8 Mean Color or Mean Intensity  PAGEREF _Toc96704985 \h 97

4.9.3.9 Extreme Points  PAGEREF _Toc96704986 \h 97

Additional Resources  PAGEREF _Toc96704987 \h 98

Exercises  PAGEREF _Toc96704988 \h 98

Goal  PAGEREF _Toc96704989 \h 98

Theory and Code  PAGEREF _Toc96704990 \h 99

4.9.4.1. Convexity Defects  PAGEREF _Toc96704991 \h 99

4.9.4.12. Point Polygon Test  PAGEREF _Toc96704992 \h 100

4.9.4.13. Match Shapes  PAGEREF _Toc96704993 \h 100

Additional Resources  PAGEREF _Toc96704994 \h 101

Exercises  PAGEREF _Toc96704995 \h 102

Goal  PAGEREF _Toc96704996 \h 102

Theory  PAGEREF _Toc96704997 \h 102

What is Hierarchy?  PAGEREF _Toc96704998 \h 102

Hierarchy Representation in OpenCV  PAGEREF _Toc96704999 \h 103

Contour Retrieval Mode  PAGEREF _Toc96705000 \h 104

4.9.5.1. RETR_LIST  PAGEREF _Toc96705001 \h 104

4.9.5.2. RETR_EXTERNAL  PAGEREF _Toc96705002 \h 105

4.9.5.3. RETR_CCOMP  PAGEREF _Toc96705003 \h 105

4.9.5.4. RETR_TREE  PAGEREF _Toc96705004 \h 107

Additional Resources  PAGEREF _Toc96705005 \h 108

Exercises  PAGEREF _Toc96705006 \h 108

Goal  PAGEREF _Toc96705007 \h 109

Theory  PAGEREF _Toc96705008 \h 109

Find Histogram  PAGEREF _Toc96705009 \h 110

4.10.1.1. Histogram Calculation in OpenCV  PAGEREF _Toc96705010 \h 110

4.10.1.2. Histogram Calculation in Numpy  PAGEREF _Toc96705011 \h 111

Plotting Histograms  PAGEREF _Toc96705012 \h 111

1. Using Matplotlib  PAGEREF _Toc96705013 \h 112

2. Using OpenCV  PAGEREF _Toc96705014 \h 113

Application of Mask  PAGEREF _Toc96705015 \h 113

Additional Resources  PAGEREF _Toc96705016 \h 114

Exercises  PAGEREF _Toc96705017 \h 114

Goal  PAGEREF _Toc96705018 \h 115

Theory  PAGEREF _Toc96705019 \h 115

Histograms Equalization in OpenCV  PAGEREF _Toc96705020 \h 117

CLAHE (Contrast Limited Adaptive Histogram Equalization)  PAGEREF _Toc96705021 \h 118

Additional Resources  PAGEREF _Toc96705022 \h 120

Exercises  PAGEREF _Toc96705023 \h 121

Goal  PAGEREF _Toc96705024 \h 121

Introduction  PAGEREF _Toc96705025 \h 121

2D Histogram in OpenCV  PAGEREF _Toc96705026 \h 121

2D Histogram in Numpy  PAGEREF _Toc96705027 \h 122

Plotting 2D Histograms  PAGEREF _Toc96705028 \h 122

Method - 1 : Using cv.imshow()  PAGEREF _Toc96705029 \h 122

Method - 2 : Using Matplotlib  PAGEREF _Toc96705030 \h 122

Method 3 : OpenCV sample style !!  PAGEREF _Toc96705031 \h 123

Additional Resources  PAGEREF _Toc96705032 \h 124

Exercises  PAGEREF _Toc96705033 \h 124

Goal  PAGEREF _Toc96705034 \h 124

Theory  PAGEREF _Toc96705035 \h 124

Algorithm in Numpy  PAGEREF _Toc96705036 \h 125

Backprojection in OpenCV  PAGEREF _Toc96705037 \h 126

Additional Resources  PAGEREF _Toc96705038 \h 128

Exercises  PAGEREF _Toc96705039 \h 129

Goal  PAGEREF _Toc96705040 \h 129

Theory  PAGEREF _Toc96705041 \h 129

Fourier Transform in Numpy  PAGEREF _Toc96705042 \h 130

Fourier Transform in OpenCV  PAGEREF _Toc96705043 \h 132

Performance Optimization of DFT  PAGEREF _Toc96705044 \h 133

Why Laplacian is a High Pass Filter?  PAGEREF _Toc96705045 \h 134

Additional Resources  PAGEREF _Toc96705046 \h 136

Exercises  PAGEREF _Toc96705047 \h 136

Goals  PAGEREF _Toc96705048 \h 136

Theory  PAGEREF _Toc96705049 \h 137

Template Matching in OpenCV  PAGEREF _Toc96705050 \h 137

Template Matching with Multiple Objects  PAGEREF _Toc96705051 \h 140

Additional Resources  PAGEREF _Toc96705052 \h 141

Exercises  PAGEREF _Toc96705053 \h 141

Goal  PAGEREF _Toc96705054 \h 141

Theory  PAGEREF _Toc96705055 \h 141

Hough Transform in OpenCV  PAGEREF _Toc96705056 \h 143

Probabilistic Hough Transform  PAGEREF _Toc96705057 \h 144

Additional Resources  PAGEREF _Toc96705058 \h 146

Exercises  PAGEREF _Toc96705059 \h 146

Goal  PAGEREF _Toc96705060 \h 147

Theory  PAGEREF _Toc96705061 \h 147

Additional Resources  PAGEREF _Toc96705062 \h 148

Exercises  PAGEREF _Toc96705063 \h 148

Goal  PAGEREF _Toc96705064 \h 148

Theory  PAGEREF _Toc96705065 \h 148

Code  PAGEREF _Toc96705066 \h 149

Additional Resources  PAGEREF _Toc96705067 \h 154

Exercises  PAGEREF _Toc96705068 \h 154

Goal  PAGEREF _Toc96705069 \h 154

Theory  PAGEREF _Toc96705070 \h 154

Demo  PAGEREF _Toc96705071 \h 157

Additional Resources  PAGEREF _Toc96705072 \h 159

Exercises  PAGEREF _Toc96705073 \h 159

Goal  PAGEREF _Toc96705074 \h 161

Explanation  PAGEREF _Toc96705075 \h 161

Additional Resources  PAGEREF _Toc96705076 \h 164

Exercises  PAGEREF _Toc96705077 \h 164

Goal  PAGEREF _Toc96705078 \h 164

Theory  PAGEREF _Toc96705079 \h 164

Harris Corner Detector in OpenCV  PAGEREF _Toc96705080 \h 166

Corner with SubPixel Accuracy  PAGEREF _Toc96705081 \h 167

Additional Resources  PAGEREF _Toc96705082 \h 168

Exercises  PAGEREF _Toc96705083 \h 169

Goal  PAGEREF _Toc96705084 \h 169

Theory  PAGEREF _Toc96705085 \h 169

Code  PAGEREF _Toc96705086 \h 170

Additional Resources  PAGEREF _Toc96705087 \h 171

Exercises  PAGEREF _Toc96705088 \h 171

Goal  PAGEREF _Toc96705089 \h 171

Theory  PAGEREF _Toc96705090 \h 171

1. Scale-space Extrema Detection  PAGEREF _Toc96705091 \h 172

2. Keypoint Localization  PAGEREF _Toc96705092 \h 173

3. Orientation Assignment  PAGEREF _Toc96705093 \h 174

4. Keypoint Descriptor  PAGEREF _Toc96705094 \h 174

5. Keypoint Matching  PAGEREF _Toc96705095 \h 174

SIFT in OpenCV  PAGEREF _Toc96705096 \h 174

Additional Resources  PAGEREF _Toc96705097 \h 176

Exercises  PAGEREF _Toc96705098 \h 176

Goal  PAGEREF _Toc96705099 \h 176

Theory  PAGEREF _Toc96705100 \h 176

SURF in OpenCV  PAGEREF _Toc96705101 \h 178

Additional Resources  PAGEREF _Toc96705102 \h 181

Exercises  PAGEREF _Toc96705103 \h 181

Goal  PAGEREF _Toc96705104 \h 181

Theory  PAGEREF _Toc96705105 \h 181

Feature Detection using FAST  PAGEREF _Toc96705106 \h 182

Machine Learning a Corner Detector  PAGEREF _Toc96705107 \h 183

Non-maximal Suppression  PAGEREF _Toc96705108 \h 183

Summary  PAGEREF _Toc96705109 \h 183

FAST Feature Detector in OpenCV  PAGEREF _Toc96705110 \h 184

Additional Resources  PAGEREF _Toc96705111 \h 185

Exercises  PAGEREF _Toc96705112 \h 185

Goal  PAGEREF _Toc96705113 \h 185

Theory  PAGEREF _Toc96705114 \h 185

STAR(CenSurE) in OpenCV  PAGEREF _Toc96705115 \h 186

BRIEF in OpenCV  PAGEREF _Toc96705116 \h 187

Additional Resources  PAGEREF _Toc96705117 \h 187

Goal  PAGEREF _Toc96705118 \h 187

Theory  PAGEREF _Toc96705119 \h 188

ORB in OpenCV  PAGEREF _Toc96705120 \h 189

Additional Resources  PAGEREF _Toc96705121 \h 190

Exercises  PAGEREF _Toc96705122 \h 190

Goal  PAGEREF _Toc96705123 \h 190

Basics of Brute-Force Matcher  PAGEREF _Toc96705124 \h 190

Brute-Force Matching with ORB Descriptors  PAGEREF _Toc96705125 \h 191

What is this Matcher Object?  PAGEREF _Toc96705126 \h 192

Brute-Force Matching with SIFT Descriptors and Ratio Test  PAGEREF _Toc96705127 \h 193

FLANN based Matcher  PAGEREF _Toc96705128 \h 194

Additional Resources  PAGEREF _Toc96705129 \h 195

Exercises  PAGEREF _Toc96705130 \h 196

Goal  PAGEREF _Toc96705131 \h 196

Basics  PAGEREF _Toc96705132 \h 196

Code  PAGEREF _Toc96705133 \h 196

Additional Resources  PAGEREF _Toc96705134 \h 198

Exercises  PAGEREF _Toc96705135 \h 198

Introduction  PAGEREF _Toc96705136 \h 199

Exposure sequence  PAGEREF _Toc96705137 \h 200

Source Code  C JavaPython  PAGEREF _Toc96705138 \h 201

Sample images  PAGEREF _Toc96705139 \h 202

Explanation  C JavaPython  PAGEREF _Toc96705140 \h 202

Results  PAGEREF _Toc96705141 \h 203

Tonemapped image  PAGEREF _Toc96705142 \h 203

Exposure fusion  PAGEREF _Toc96705143 \h 204

Additional Resources  PAGEREF _Toc96705144 \h 205

Goal  PAGEREF _Toc96705145 \h 206

Code  PAGEREF _Toc96705146 \h 206

Explanation  PAGEREF _Toc96705147 \h 208

Camera models  PAGEREF _Toc96705148 \h 209

Try it out  PAGEREF _Toc96705149 \h 210

Stitching detailed (python opencv >4.0.1)  C Python  PAGEREF _Toc96705150 \h 212

Goals  PAGEREF _Toc96705151 \h 216

Code  C JavaPython  PAGEREF _Toc96705152 \h 216

Explanation  C JavaPython  PAGEREF _Toc96705153 \h 218

Results  PAGEREF _Toc96705154 \h 219

References  PAGEREF _Toc96705155 \h 221

Goal  PAGEREF _Toc96705156 \h 221

Meanshift  PAGEREF _Toc96705157 \h 221

Meanshift in OpenCV  C PythonJava  PAGEREF _Toc96705158 \h 223

Camshift  PAGEREF _Toc96705159 \h 225

Camshift in OpenCV  C PythonJava  PAGEREF _Toc96705160 \h 226

Additional Resources  PAGEREF _Toc96705161 \h 229

Exercises  PAGEREF _Toc96705162 \h 229

Goal  PAGEREF _Toc96705163 \h 230

Optical Flow  PAGEREF _Toc96705164 \h 230

Lucas-Kanade method  PAGEREF _Toc96705165 \h 231

Lucas-Kanade Optical Flow in OpenCV  C PythonJava  PAGEREF _Toc96705166 \h 232

Dense Optical Flow in OpenCV  C PythonJava  PAGEREF _Toc96705167 \h 235

Goal  PAGEREF _Toc96705168 \h 237

Theory  PAGEREF _Toc96705169 \h 238

Haar-cascade Detection in OpenCV  C JavaPython  PAGEREF _Toc96705170 \h 240

Result  PAGEREF _Toc96705171 \h 242

Additional Resources  PAGEREF _Toc96705172 \h 243

Introduction  PAGEREF _Toc96705173 \h 243

Important notes  PAGEREF _Toc96705174 \h 244

Preparation of the training data  PAGEREF _Toc96705175 \h 244

Negative Samples  PAGEREF _Toc96705176 \h 245

Positive Samples  PAGEREF _Toc96705177 \h 245

Using OpenCV's integrated annotation tool  PAGEREF _Toc96705178 \h 248

Cascade Training  PAGEREF _Toc96705179 \h 249

Visualising Cascade Classifiers  PAGEREF _Toc96705180 \h 251

Goal  PAGEREF _Toc96705181 \h 253

What is a SVM?  PAGEREF _Toc96705182 \h 253

How is the optimal hyperplane computed?  PAGEREF _Toc96705183 \h 255

Source Code  C JavaPython  PAGEREF _Toc96705184 \h 256

Explanation  C JavaPython  PAGEREF _Toc96705185 \h 258

Results  PAGEREF _Toc96705186 \h 260

Goal  PAGEREF _Toc96705187 \h 261

Motivation  PAGEREF _Toc96705188 \h 261

Extension of the Optimization Problem  PAGEREF _Toc96705189 \h 262

Source Code  C JavaPython  PAGEREF _Toc96705190 \h 264

Explanation  C JavaPython  PAGEREF _Toc96705191 \h 268

Results  PAGEREF _Toc96705192 \h 271

Goal  PAGEREF _Toc96705193 \h 272

What is PCA?  PAGEREF _Toc96705194 \h 272

How are the eigenvectors and eigenvalues computed?  PAGEREF _Toc96705195 \h 273

Source Code  C JavaPython  PAGEREF _Toc96705196 \h 275

Explanation  C JavaPython  PAGEREF _Toc96705197 \h 278

Results  PAGEREF _Toc96705198 \h 281

Goal  PAGEREF _Toc96705199 \h 283

Basics  PAGEREF _Toc96705200 \h 283

Code  PAGEREF _Toc96705201 \h 285

Setup  PAGEREF _Toc96705202 \h 286

Calibration  PAGEREF _Toc96705203 \h 287

Undistortion  PAGEREF _Toc96705204 \h 287

Re-projection Error  PAGEREF _Toc96705205 \h 289

Additional Resources  PAGEREF _Toc96705206 \h 289

Exercises  PAGEREF _Toc96705207 \h 289

Goal  PAGEREF _Toc96705208 \h 290

Basics  PAGEREF _Toc96705209 \h 290

Render a Cube  PAGEREF _Toc96705210 \h 292

Additional Resources  PAGEREF _Toc96705211 \h 293

Exercises  PAGEREF _Toc96705212 \h 293

Goal  PAGEREF _Toc96705213 \h 293

Basic Concepts  PAGEREF _Toc96705214 \h 293

Code  PAGEREF _Toc96705215 \h 295

Additional Resources  PAGEREF _Toc96705216 \h 297

Exercises  PAGEREF _Toc96705217 \h 297

Goal  PAGEREF _Toc96705218 \h 298

Basics  PAGEREF _Toc96705219 \h 298

Code  PAGEREF _Toc96705220 \h 299

Additional Resources  PAGEREF _Toc96705221 \h 300

Exercises  PAGEREF _Toc96705222 \h 300

Goal  PAGEREF _Toc96705223 \h 301

Theory  PAGEREF _Toc96705224 \h 301

kNN in OpenCV  PAGEREF _Toc96705225 \h 303

Additional Resources  PAGEREF _Toc96705226 \h 305

Exercises  PAGEREF _Toc96705227 \h 305

Goal  PAGEREF _Toc96705228 \h 306

OCR of Hand-written Digits  PAGEREF _Toc96705229 \h 306

OCR of the English Alphabet  PAGEREF _Toc96705230 \h 307

Additional Resources  PAGEREF _Toc96705231 \h 308

Exercises  PAGEREF _Toc96705232 \h 308

Goal  PAGEREF _Toc96705233 \h 309

Theory  PAGEREF _Toc96705234 \h 309

Linearly Separable Data  PAGEREF _Toc96705235 \h 309

Non-Linearly Separable Data  PAGEREF _Toc96705236 \h 310

Additional Resources  PAGEREF _Toc96705237 \h 312

Exercises  PAGEREF _Toc96705238 \h 312

Goal  PAGEREF _Toc96705239 \h 313

OCR of Hand-written Digits  PAGEREF _Toc96705240 \h 313

Additional Resources  PAGEREF _Toc96705241 \h 315

Exercises  PAGEREF _Toc96705242 \h 315

Goal  PAGEREF _Toc96705243 \h 316

Theory  PAGEREF _Toc96705244 \h 316

T-shirt size problem  PAGEREF _Toc96705245 \h 316

How does it work ?  PAGEREF _Toc96705246 \h 317

Additional Resources  PAGEREF _Toc96705247 \h 320

Exercises  PAGEREF _Toc96705248 \h 320

Goal  PAGEREF _Toc96705249 \h 320

Understanding Parameters  PAGEREF _Toc96705250 \h 320

Input parameters  PAGEREF _Toc96705251 \h 320

Output parameters  PAGEREF _Toc96705252 \h 321

8.3.2.1. Data with Only One Feature  PAGEREF _Toc96705253 \h 321

8.3.2.2. Data with Multiple Features  PAGEREF _Toc96705254 \h 323

8.3.2.3. Color Quantization  PAGEREF _Toc96705255 \h 324

Additional Resources  PAGEREF _Toc96705256 \h 326

Exercises  PAGEREF _Toc96705257 \h 326

Goal  PAGEREF _Toc96705258 \h 327

Theory  PAGEREF _Toc96705259 \h 327

Image Denoising in OpenCV  PAGEREF _Toc96705260 \h 328

1. cv.fastNlMeansDenoisingColored()  PAGEREF _Toc96705261 \h 329

2. cv.fastNlMeansDenoisingMulti()  PAGEREF _Toc96705262 \h 330

Additional Resources  PAGEREF _Toc96705263 \h 331

Exercises  PAGEREF _Toc96705264 \h 332

Goal  PAGEREF _Toc96705265 \h 332

Basics  PAGEREF _Toc96705266 \h 332

Code  PAGEREF _Toc96705267 \h 333

Additional Resources  PAGEREF _Toc96705268 \h 334

Exercises  PAGEREF _Toc96705269 \h 334

Goal  PAGEREF _Toc96705270 \h 334

Theory  PAGEREF _Toc96705271 \h 335

Exposure sequence HDR  PAGEREF _Toc96705272 \h 335

1. Loading exposure images into a list  PAGEREF _Toc96705273 \h 336

2. Merge exposures into HDR image  PAGEREF _Toc96705274 \h 336

3. Tonemap HDR image  PAGEREF _Toc96705275 \h 336

4. Merge exposures using Mertens fusion  PAGEREF _Toc96705276 \h 337

5. Convert to 8-bit and save  PAGEREF _Toc96705277 \h 337

Results  PAGEREF _Toc96705278 \h 337

Debevec:  PAGEREF _Toc96705279 \h 337

Robertson:  PAGEREF _Toc96705280 \h 338

Mertenes Fusion:  PAGEREF _Toc96705281 \h 338

Estimating Camera Response Function  PAGEREF _Toc96705282 \h 339

Additional Resources  PAGEREF _Toc96705283 \h 340

Exercises  PAGEREF _Toc96705284 \h 340

Introduction  PAGEREF _Toc96705285 \h 341

Exposure sequence  PAGEREF _Toc96705286 \h 342

Source Code  C JavaPython  PAGEREF _Toc96705287 \h 342

Sample images  PAGEREF _Toc96705288 \h 343

Explanation  C JavaPython  PAGEREF _Toc96705289 \h 344

Results  PAGEREF _Toc96705290 \h 345

Tonemapped image  PAGEREF _Toc96705291 \h 345

Exposure fusion  PAGEREF _Toc96705292 \h 346

Additional Resources  PAGEREF _Toc96705293 \h 346

Goal  PAGEREF _Toc96705294 \h 347

Code  PAGEREF _Toc96705295 \h 347

Explanation  PAGEREF _Toc96705296 \h 350

Camera models  PAGEREF _Toc96705297 \h 351

Try it out  PAGEREF _Toc96705298 \h 351

Stitching detailed (python opencv >4.0.1)  C Python  PAGEREF _Toc96705299 \h 353

Goals  PAGEREF _Toc96705300 \h 357

Code  C JavaPython  PAGEREF _Toc96705301 \h 358

Explanation  C JavaPython  PAGEREF _Toc96705302 \h 359

Results  PAGEREF _Toc96705303 \h 360

References  PAGEREF _Toc96705304 \h 362

Goal  PAGEREF _Toc96705305 \h 362

Meanshift  PAGEREF _Toc96705306 \h 362

Meanshift in OpenCV  C PythonJava  PAGEREF _Toc96705307 \h 364

Camshift  PAGEREF _Toc96705308 \h 366

Camshift in OpenCV  C PythonJava  PAGEREF _Toc96705309 \h 367

Additional Resources  PAGEREF _Toc96705310 \h 370

Exercises  PAGEREF _Toc96705311 \h 370

Goal  PAGEREF _Toc96705312 \h 371

Optical Flow  PAGEREF _Toc96705313 \h 371

Lucas-Kanade method  PAGEREF _Toc96705314 \h 372

Lucas-Kanade Optical Flow in OpenCV  C PythonJava  PAGEREF _Toc96705315 \h 373

Dense Optical Flow in OpenCV  C PythonJava  PAGEREF _Toc96705316 \h 376

Goal  PAGEREF _Toc96705317 \h 379

Theory  PAGEREF _Toc96705318 \h 379

Haar-cascade Detection in OpenCV  C JavaPython  PAGEREF _Toc96705319 \h 381

Result  PAGEREF _Toc96705320 \h 383

Additional Resources  PAGEREF _Toc96705321 \h 384

Introduction  PAGEREF _Toc96705322 \h 384

Important notes  PAGEREF _Toc96705323 \h 385

Preparation of the training data  PAGEREF _Toc96705324 \h 385

Negative Samples  PAGEREF _Toc96705325 \h 386

Positive Samples  PAGEREF _Toc96705326 \h 386

Using OpenCV's integrated annotation tool  PAGEREF _Toc96705327 \h 389

Cascade Training  PAGEREF _Toc96705328 \h 390

Visualising Cascade Classifiers  PAGEREF _Toc96705329 \h 392

Goal  PAGEREF _Toc96705330 \h 394

What is a SVM?  PAGEREF _Toc96705331 \h 394

How is the optimal hyperplane computed?  PAGEREF _Toc96705332 \h 396

Source Code  C JavaPython  PAGEREF _Toc96705333 \h 397

Explanation  C JavaPython  PAGEREF _Toc96705334 \h 399

Results  PAGEREF _Toc96705335 \h 401

Goal  PAGEREF _Toc96705336 \h 402

Motivation  PAGEREF _Toc96705337 \h 402

Extension of the Optimization Problem  PAGEREF _Toc96705338 \h 403

Source Code  C JavaPython  PAGEREF _Toc96705339 \h 404

Explanation  C JavaPython  PAGEREF _Toc96705340 \h 409

Results  PAGEREF _Toc96705341 \h 412

Goal  PAGEREF _Toc96705342 \h 413

What is PCA?  PAGEREF _Toc96705343 \h 413

How are the eigenvectors and eigenvalues computed?  PAGEREF _Toc96705344 \h 414

Source Code  C JavaPython  PAGEREF _Toc96705345 \h 416

Explanation  C JavaPython  PAGEREF _Toc96705346 \h 419

Results  PAGEREF _Toc96705347 \h 422

Goal  PAGEREF _Toc96705348 \h 423

How OpenCV-Python bindings are generated?  PAGEREF _Toc96705349 \h 423

How to extend new modules to Python?  PAGEREF _Toc96705350 \h 424