Computes a dense optical flow using the Gunnar Farneback's algorithm.
Namespace: OpenCvSharp.CPlusPlus
Assembly: OpenCvSharp.CPlusPlus (in OpenCvSharp.CPlusPlus.dll) Version: 1.0.0.0 (1.0.0.0)
Syntax
public static void CalcOpticalFlowFarneback( InputArray prev, InputArray next, InputOutputArray flow, double pyrScale, int levels, int winsize, int iterations, int polyN, double polySigma, OpticalFlowFlags flags )
Parameters
- prev
- Type: OpenCvSharp.CPlusPlusInputArray
first 8-bit single-channel input image. - next
- Type: OpenCvSharp.CPlusPlusInputArray
second input image of the same size and the same type as prev. - flow
- Type: OpenCvSharp.CPlusPlusInputOutputArray
computed flow image that has the same size as prev and type CV_32FC2. - pyrScale
- Type: SystemDouble
parameter, specifying the image scale (<1) to build pyramids for each image; pyrScale=0.5 means a classical pyramid, where each next layer is twice smaller than the previous one. - levels
- Type: SystemInt32
number of pyramid layers including the initial image; levels=1 means that no extra layers are created and only the original images are used. - winsize
- Type: SystemInt32
averaging window size; larger values increase the algorithm robustness to image noise and give more chances for fast motion detection, but yield more blurred motion field. - iterations
- Type: SystemInt32
number of iterations the algorithm does at each pyramid level. - polyN
- Type: SystemInt32
size of the pixel neighborhood used to find polynomial expansion in each pixel; larger values mean that the image will be approximated with smoother surfaces, yielding more robust algorithm and more blurred motion field, typically poly_n =5 or 7. - polySigma
- Type: SystemDouble
standard deviation of the Gaussian that is used to smooth derivatives used as a basis for the polynomial expansion; for polyN=5, you can set polySigma=1.1, for polyN=7, a good value would be polySigma=1.5. - flags
- Type: OpenCvSharp.CPlusPlusOpticalFlowFlags
operation flags that can be a combination of OPTFLOW_USE_INITIAL_FLOW and/or OPTFLOW_FARNEBACK_GAUSSIAN
See Also