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