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OpenCV
| Camera Calibration And 3D Reconstruction | ||||
| Icon | Name | Description / Applications | Modules | |
|---|---|---|---|---|
|  | cvCalibrateRobotWorldHandEye |   | Computes Robot-World and Hand-Eye calibration matrices. | OpenCV | 
|  | cvCalibrateCamera |   | Finds the camera intrinsic and extrinsic parameters from pairs of corresponding image and object points arrays. | OpenCV | 
|  | cvCalibrateHandEye |   | Computes Hand-Eye calibration matrices. | OpenCV | 
|  | cvCalibrationMatrixValues |   | Returns camera characteristics from camera matrix. | OpenCV | 
|  | cvCheckChessboard |   | Check chessboard corners. | OpenCV | 
|  | cvConvertPointsFromHomogeneous |   | Converts points from homogeneous to Euclidean space. | OpenCV | 
|  | cvConvertPointsToHomogeneous |   | Converts points from Euclidean to homogeneous space. | OpenCV | 
|  | cvCorrectMatches |   | Refines coordinates of corresponding points. | OpenCV | 
|  | cvCorrespondEpilines |   | Computes epilines in one view for a set of points in the other view. | OpenCV | 
|  | cvDecomposeEssentialMat |   | Decompose an essential matrix to possible rotations and translation. | OpenCV | 
|  | cvDecomposeHomographyMat |   | Decompose a homography matrix to rotation(s), translation(s) and plane normal(s). | OpenCV | 
|  | cvDecomposeProjectionMatrix |   | Decomposes a projection matrix into a rotation matrix and a camera intrinsic matrix. | OpenCV | 
|  | cvDrawChessboardCorners |   | Renders the detected chessboard corners. | OpenCV | 
|  | cvDrawFrameAxes |   | Draw axes of the world/object coordinate system from pose estimation. | OpenCV | 
|  | cvEstimateAffine2D |   | Computes an optimal affine transformation between two 2D point sets. | OpenCV | 
|  | cvEstimateAffine3D |   | Computes optimal affine transformation between two 3D point sets. | OpenCV | 
|  | cvEstimateAffinePartial2D |   | Computes an optimal limited affine transformation with 4 degrees of freedom between two 2D point sets. | OpenCV | 
|  | cvEstimateChessboardSharpness |   | Estimates the sharpness of a detected chessboard. Image sharpness, as well as brightness, are a critical parameter for accuracte camera calibration. | OpenCV | 
|  | cvFindChessboardCorners |   | Finds the positions of the internal corners of the chessboard. | OpenCV | 
|  | cvFindCirclesGrid |   | Finds the centers in the grid of circles. | OpenCV | 
|  | cvFindEssentialMat |   | Calculates an essential matrix from the corresponding points in two images. | OpenCV | 
|  | cvFindHomography |   | Finds a perspective transformation between two planes. | OpenCV | 
|  | cvFisheyeCalibrateCamera |   | Finds the camera intrinsic and extrinsic parameters from pairs of corresponding image and object points arrays. | OpenCV | 
|  | cvGetOptimalNewCameraMatrix |   | Computes the new camera matrix based on the free scaling parameter. | OpenCV | 
|  | cvInitCameraMatrix2D |   | Finds the initial camera matrix from the 3D-2D point correspondences. | OpenCV | 
|  | cvMatMulDeriv |   | Computes partial derivatives of the matrix product for each multiplied matrix. | OpenCV | 
|  | cvProjectPoints |   | Projects 3D points to an image plane. | OpenCV | 
|  | cvReprojectImageTo3D |   | Projects a disparity image to 3D space. | OpenCV | 
|  | cvRodrigues_MatToVec |   | Converts a Rotation Matrix to a Rvec vector. | OpenCV | 
|  | cvRodrigues_VecToMat |   | Converts a Rvec vector to a Rotation Matrix. | OpenCV | 
|  | cvSolvePnP |   | Finds an object pose from 3D-2D point correspondences. This function returns the rotation and the translation vectors that transform a 3D point expressed in the object coordinate frame to the camera coordinate frame. | OpenCV | 
|  | cvSolvePnPRansac |   | Finds an object pose from 3D-2D point correspondences using the RANSAC scheme. | OpenCV | 
|  | cvSolvePnPRefineLM |   | Refine a pose (the translation and the rotation that transform a 3D point expressed in the object coordinate frame to the camera coordinate frame) from a 3D-2D point correspondences and starting from an initial solution. | OpenCV | 
|  | cvSolvePnPRefineVVS |   | Refine a pose (the translation and the rotation that transform a 3D point expressed in the object coordinate frame to the camera coordinate frame) from a 3D-2D point correspondences and starting from an initial solution. | OpenCV | 
|  | cvStereoBM |   | Computes stereo correspondence using the block matching algorithm. | OpenCV | 
|  | cvStereoCalibrate |   | Performs stereo calibration of two cameras. | OpenCV | 
|  | cvStereoRectify |   | Computes rectification transforms for each head of a calibrated stereo camera. | OpenCV | 
|  | cvStereoSGBM |   | Computes stereo correspondence using the semi-global block matching algorithm. | OpenCV | 
|  | cvTriangulatePoints |   | This function reconstructs 3-dimensional points (in homogeneous coordinates) by using their observations with a stereo camera. | OpenCV | 
|  | CreateCameraMatrix |   | Creates an intrinsic camera matrix from focal lengths and a principal point. | OpenCV | 
|  | CreateChessboardMatrix |   | Creates simple array with object points. | OpenCV | 
|  | CreateCirclesGridMatrix |   | Creates simple array with object points. | OpenCV | 
| Computational Photography | ||||
| Icon | Name | Description / Applications | Modules | |
|  | cvColorChange |   | Given an original color image, two differently colored versions of this image can be mixed seamlessly. | OpenCV | 
|  | cvDecolor |   | Transforms a color image to a grayscale image. It is a basic tool in digital printing, stylized black-and-white photograph rendering, and in many single channel image processing applications. | OpenCV | 
|  | cvDenoise_TVL1 |   | Primal-dual algorithm is an algorithm for solving special types of variational problems (that is, finding a function to minimize some functional). As the image denoising, in particular, may be seen as the variational problem, primal-dual algorithm then can be used to perform denoising and this is exactly what is implemented. | OpenCV | 
|  | cvDetailEnhance |   | This filter enhances the details of a particular image. | OpenCV | 
|  | cvEdgePreservingFilter |   | Filtering is the fundamental operation in image and video processing. Edge-preserving smoothing filters are used in many different applications. | OpenCV | 
|  | cvFastNlMeansDenoising |   | Perform image denoising using Non-local Means Denoising algorithm. | OpenCV | 
|  | cvFastNlMeansDenoisingColored |   | Perform image denoising using Non-local Means Denoising algorithm. | OpenCV | 
|  | cvFastNlMeansDenoisingMulti |   | Perform image denoising using Non-local Means Denoising algorithm. | OpenCV | 
|  | cvIlluminationChange |   | Applying an appropriate non-linear transformation to the gradient field inside the selection and then integrating back with a Poisson solver, modifies locally the apparent illumination of an image. | OpenCV | 
|  | cvSeamlessClone |   | Image editing tasks concern either global changes (color/intensity corrections, filters, deformations) or local changes concerned to a selection. | OpenCV | 
|  | cvTextureFlattening |   | By retaining only the gradients at edge locations, before integrating with the Poisson solver, one washes out the texture of the selected region, giving its contents a flat aspect. Here Canny Edge Detector is used. | OpenCV | 
| Configuration | ||||
| Icon | Name | Description / Applications | Modules | |
|  | cvSetNumThreads |   | Configures number of threads used by OpenCV. | OpenCV | 
|  | cvSetUseOptimized |   | Enables or disables the optimized code. | OpenCV | 
| Drawing | ||||
| Icon | Name | Description / Applications | Modules | |
|  | cvArrowedLine |   | Draws a arrow segment connecting two points. | OpenCV | 
|  | cvCircle |   | Draws a circle. | OpenCV | 
|  | cvDrawMarker |   | Draws a marker on a predefined position in an image. | OpenCV | 
|  | cvEllipse |   | Draws a simple or thick elliptic arc or fills an ellipse sector. | OpenCV | 
|  | cvFillConvexPoly |   | Fills a convex shape. | OpenCV | 
|  | cvFillPoly |   | Fills the area bounded by one or more polygons. | OpenCV | 
|  | cvGetFontScaleFromHeight |   | Calculates the font-specific size to use to achieve a given height in pixels. | OpenCV | 
|  | cvGetTextSize |   | Calculates the width and height of a text string. | OpenCV | 
|  | cvLine |   | Draws a line segment connecting two points. | OpenCV | 
|  | cvPolylines |   | Draws several polygonal curves. | OpenCV | 
|  | cvPutText |   | Draws a text string. | OpenCV | 
|  | cvRectangle |   | Draws a simple, thick, or filled up-right rectangle. | OpenCV | 
| Feature 2D Framework | ||||
| Icon | Name | Description / Applications | Modules | |
|  | cvBOWTrainerFeature2D |   | Kmeans-based class to train visual vocabulary using the bag of visual words approach. | OpenCV | 
|  | cvDetectFeature2D_BRISK |   | BRISK keypoint detector and descriptor extractor. | OpenCV | 
|  | cvDetectFeature2D_FastFeatureDetector |   | Feature detection using the FAST method. | OpenCV | 
|  | cvDetectFeature2D_GFTT |   | Feature detection using the good features to track function. | OpenCV | 
|  | cvDetectFeature2D_KAZE |   | KAZE keypoint detector and descriptor extractor. | OpenCV | 
|  | cvDetectFeature2D_ORB |   | ORB keypoint detector and descriptor extractor. | OpenCV | 
|  | cvDetectFeature2D_SIFT |   | Extracting keypoints and computing descriptors using the Scale Invariant Feature Transform (SIFT) algorithm. | OpenCV | 
|  | cvDetectFeature2D_SimpleBlobDetector |   | Extracting blobs from an image. | OpenCV | 
|  | cvMatchFeature2D |   | Matchers of keypoint descriptors. | OpenCV | 
| Feature Detection | ||||
| Icon | Name | Description / Applications | Modules | |
|  | cvCanny |   | Finds edges in an image using Canny algorithm. | OpenCV | 
|  | cvCornerEigenValsAndVecs |   | Calculates eigenvalues and eigenvectors of image blocks for corner detection. | OpenCV | 
|  | cvCornerHarris |   | Harris corner detector. | OpenCV | 
|  | cvCornerMinEigenVal |   | Calculates the minimal eigenvalue of gradient matrices for corner detection. | OpenCV | 
|  | cvCornerSubPix |   | Refines the corner locations. | OpenCV | 
|  | cvGoodFeaturesToTrack |   | Determines strong corners on an image. | OpenCV | 
|  | cvHoughCircles |   | Finds circles in a grayscale image using a Hough transform. | OpenCV | 
|  | cvHoughLines |   | Finds lines in a binary image using standard Hough transform. | OpenCV | 
|  | cvHoughLinesP |   | Finds lines segments in a binary image using probabilistic Hough transform. | OpenCV | 
|  | cvPreCornerDetect |   | Calculates the feature map for corner detection. | OpenCV | 
| Geometric Image Transformations | ||||
| Icon | Name | Description / Applications | Modules | |
|  | cvGetAffineTransform |   | Calculates the affine transform from 3 corresponding points. Prepares matrix to be used with cvWarpAffine. | OpenCV | 
|  | cvGetDefaultNewCameraMatrix |   | Returns the default new camera matrix. | OpenCV | 
|  | cvGetPerspectiveTransform |   | Calculates the perspective transform from four pairs of corresponding points. Prepares matrix to be used with cvWarpPerspective. | OpenCV | 
|  | cvGetRectSubPix |   | Retrieves the pixel rectangle from an image with sub-pixel accuracy. | OpenCV | 
|  | cvGetRotationMatrix2D |   | Calculates the affine matrix of 2D rotation. Prepares matrix to be used with cvWarpAffine. | OpenCV | 
|  | cvInitUndistortRectifyMap |   | Computes the undistortion and rectification transformation map. | OpenCV | 
|  | cvInvertAffineTransform |   | Inverts an affine transformation. Prepares matrix to be used with cvWarpAffine. | OpenCV | 
|  | cvRemap |   | Applies a generic geometrical transformation to the image. | OpenCV | 
|  | cvResize |   | Resizes an image. | OpenCV | 
|  | cvUndistort |   | Transforms an image to compensate for lens distortion. | OpenCV | 
|  | cvUndistortPoints |   | Undistorts points. | OpenCV | 
|  | cvWarpAffine |   | Applies an affine transformation to an image. | OpenCV | 
|  | cvWarpPerspective |   | Applies a perspective transformation to an image. | OpenCV | 
|  | cvWarpPolar |   | Remaps an image to polar or semilog-polar coordinates space. | OpenCV | 
| Image Filtering | ||||
| Icon | Name | Description / Applications | Modules | |
|  | cvBilateralFilter |   | Applies bilateral filter to the image. | OpenCV | 
|  | cvBlur |   | Smoothes image using normalized box filter. | OpenCV | 
|  | cvBorderInterpolate |   | Computes source location of extrapolated pixel. | OpenCV | 
|  | cvBoxFilter |   | Smoothes an image using box filter. | OpenCV | 
|  | cvBuildPyramid |   | Constructs Gaussian pyramid for an image. | OpenCV | 
|  | cvCopyMakeBorder |   | Forms a border around the image. | OpenCV | 
|  | cvDilate |   | Dilates an image by using a specific structuring element. | OpenCV | 
|  | cvErode |   | Erodes an image by using a specific structuring element. | OpenCV | 
|  | cvFilter2D |   | Convolves an image with the kernel. | OpenCV | 
|  | cvGaussianBlur |   | Smoothes image using a Gaussian filter. | OpenCV | 
|  | cvGetDerivKernels |   | Returns filter coefficients for computing spatial image derivatives. Prepares matrices to be used with cvSepFilter2D or cvFilter2D. | OpenCV | 
|  | cvGetGaborKernel |   | Creates a Gabor Filter kernel. Prepares matrix to be used with cvSepFilter2D or cvFilter2D. | OpenCV | 
|  | cvGetGaussianKernel |   | Returns Gaussian filter coefficients. Prepares matrix to be used with cvSepFilter2D or cvFilter2D. | OpenCV | 
|  | cvGetStructuringElement |   | Returns the structuring element of the specified size and shape for morphological operations. Prepares element to be used with cvErode, cvDilate or cvMorphologyEx. | OpenCV | 
|  | cvLaplacian |   | Calculates the Laplacian of an image. | OpenCV | 
|  | cvMedianBlur |   | Smoothes image using median filter. | OpenCV | 
|  | cvMorphologyDefaultBorderValue |   | Returns magic border value for erosion and dilation. | OpenCV | 
|  | cvMorphologyEx |   | Performs advanced morphological transformations. | OpenCV | 
|  | cvPyrDown |   | Smoothes an image and downsamples it. | OpenCV | 
|  | cvPyrUp |   | Upsamples an image and then smoothes it. | OpenCV | 
|  | cvScharr |   | Calculates the first x- or y- image derivative using Scharr operator. | OpenCV | 
|  | cvSepFilter2D |   | Applies separable linear filter to an image. | OpenCV | 
|  | cvSobel |   | Calculates the first, second, third or mixed image derivatives using an extended Sobel operator. | OpenCV | 
|  | cvSqrBoxFilter |   | Smoothes an image using square box filter. | OpenCV | 
| Miscellaneous Image Transformations | ||||
| Icon | Name | Description / Applications | Modules | |
|  | cvAdaptiveThreshold |   | Applies an adaptive threshold to an image. | OpenCV | 
|  | cvApplyColorMap |   | Apply color map to image. | OpenCV | 
|  | cvBlendLinear |   | Blend images. | OpenCV | 
|  | cvCvtColor |   | Converts image from one color space to another. | OpenCV | 
|  | cvDistanceTransform |   | Calculates the distance to the closest zero pixel for each pixel of the source image. | OpenCV | 
|  | cvFloodFill |   | Fills a connected component with the given color. | OpenCV | 
|  | cvGrabCut |   | Runs the GrabCut algorithm. | OpenCV | 
|  | cvInpaint |   | Inpaints the selected region in the image. | OpenCV | 
|  | cvIntegral |   | Calculates the integral of an image. | OpenCV | 
|  | cvPyrMeanShiftFiltering |   | Performs an initial step of Mean Shift Filtering algorithm. | OpenCV | 
|  | cvThreshold |   | Applies a fixed-level threshold to each image element. | OpenCV | 
|  | cvWatershed |   | Does marker-based image segmentation using watershed algorithm. | OpenCV | 
| Motion Analysis and Object Tracking | ||||
| Icon | Name | Description / Applications | Modules | |
|  | cvAccumulate |   | Adds image to the accumulator. | OpenCV | 
|  | cvAccumulateProduct |   | Adds the per-element product of two input images to the accumulator. | OpenCV | 
|  | cvAccumulateSquare |   | Adds the square of the source image to the accumulator. | OpenCV | 
|  | cvAccumulateWeighted |   | Updates the running average. | OpenCV | 
|  | cvBackgroundSubtractorKNN |   | K-nearest neighbours based background segmentation algorithm. | OpenCV | 
|  | cvBackgroundSubtractorMOG2 |   | Estimates the background of the image sequence using Mixture Of Gaussians model. | OpenCV | 
|  | cvCamShift |   | Finds an moving object center, size, and orientation. | OpenCV | 
|  | cvComputeECC |   | Computes the Enhanced Correlation Coefficient value between two images. | OpenCV | 
|  | cvDISOpticalFlow |   | DIS optical flow algorithm. | OpenCV | 
|  | cvFarnebackOpticalFlow |   | Computing a dense optical flow using the Gunnar Farneback's algorithm. | OpenCV | 
|  | cvKalmanFilter |   | Standard Kalman filter. | OpenCV | 
|  | cvPhaseCorrelate |   | The function is used to detect translational shifts that occur between two images. | OpenCV | 
|  | cvSparsePyrLKOpticalFlow |   | Calculate an optical flow for a sparse feature set using the iterative Lucas-Kanade method with pyramids. | OpenCV | 
| Object Detection | ||||
| Icon | Name | Description / Applications | Modules | |
|  | cvMatchTemplate |   | Compares a template against overlapped image regions. | OpenCV | 
| Histogram | ||||
| Icon | Name | Description / Applications | Modules | |
|  | cvCalcBackProject |   | Calculates array histogram. This function perform cvCalcHist inside. | OpenCV | 
|  | cvCalcHist |   | Calculates array histogram. | OpenCV | 
|  | cvCLAHE |   | Equalizes histogram of image using adaptive histogram equalization. | OpenCV | 
|  | cvCompareHist |   | The function compares two dense or two sparse histograms using the specified method. | OpenCV | 
|  | cvEqualizeHist |   | Equalizes the histogram of a grayscale image. | OpenCV | 
| Stitching | ||||
| Icon | Name | Description / Applications | Modules | |
|  | cvStitching |   | Very simple high level image stitching. | OpenCV | 
| Structural Analysis and Shape Descriptors | ||||
| Icon | Name | Description / Applications | Modules | |
|  | cvApproxPolyDP |   | Approximates polygonal curve(s) with the specified precision. | OpenCV | 
|  | cvArcLength |   | Calculates a contour perimeter or a curve length. | OpenCV | 
|  | cvBoundingRect |   | Calculates the up-right bounding rectangle of a point set. | OpenCV | 
|  | cvConnectedComponents |   | Computes the connected components labeled image of boolean image. | OpenCV | 
|  | cvConnectedComponentsWithStats |   | Computes the connected components labeled image of boolean image and also produces a statistics output for each label | OpenCV | 
|  | cvContourArea |   | Calculates the contour area. | OpenCV | 
|  | cvConvexHull |   | Finds the convex hull of a point set. | OpenCV | 
|  | cvDrawContours |   | Draws contour outlines or filled contours. | OpenCV | 
|  | cvFindContours |   | Finds the contours in a binary image. | OpenCV | 
|  | cvFitEllipse |   | Fits an ellipse around a set of 2D points. | OpenCV | 
|  | cvFitEllipseAMS |   | Fits an ellipse around a set of 2D points. | OpenCV | 
|  | cvFitEllipseDirect |   | Fits an ellipse around a set of 2D points. | OpenCV | 
|  | cvFitLine |   | Fits a line to a 2D or 3D point set. | OpenCV | 
|  | cvGeneralizedHoughBallard_Detection |   | Finds arbitrary template in the grayscale image using Generalized Hough Transform. | OpenCV | 
|  | cvGeneralizedHoughBallard_Initialization |   | Finds arbitrary template in the grayscale image using Generalized Hough Transform. | OpenCV | 
|  | cvGeneralizedHoughGuil_Detection |   | Finds arbitrary template in the grayscale image using Generalized Hough Transform. | OpenCV | 
|  | cvGeneralizedHoughGuil_Initialization |   | Finds arbitrary template in the grayscale image using Generalized Hough Transform. | OpenCV | 
|  | cvHuMoments |   | Calculates Hu moments of the image. | OpenCV | 
|  | cvIntersectConvexConvex |   | Finds intersection of two convex polygons. | OpenCV | 
|  | cvIsContourConvex |   | Tests contour convexity. | OpenCV | 
|  | cvMatchShapes_Images |   | Compares two shapes. | OpenCV | 
|  | cvMatchShapes_Polygon |   | Compares two shapes. | OpenCV | 
|  | cvMinAreaRect |   | Finds a rotated rectangle of the minimum area enclosing the input 2D point set. | OpenCV | 
|  | cvMinEnclosingCircle |   | Finds the minimum area circle enclosing a 2D point set. | OpenCV | 
|  | cvMinEnclosingTriangle |   | Finds a rotated triangle of the minimum area enclosing the input 2D point set. | OpenCV | 
|  | cvMoments |   | Calculates image moments. | OpenCV | 
|  | cvPointPolygonTest |   | Performs point-in-contour test. | OpenCV | 
| Video Analysis | ||||
| Icon | Name | Description / Applications | Modules | |
|  | cvCalcOpticalFlowFarneback |   | Computes a dense optical flow using the Gunnar Farneback's algorithm. | OpenCV | 
|  | cvCalcOpticalFlowPyrLK |   | Calculates an optical flow for a sparse feature set using the iterative Lucas-Kanade method with pyramids. | OpenCV | 

