Function:TrackFeatures

CUVI Feature tracker tracks input features from frame 1 onto frame 2. The function is ideal for tracking selected number of features through an image sequence or a video stream. This is a custom algorithm and does not use optical flows to estimate motion. Check out Motion Estimate section for more details on Optical Flow based motion tracking.

Function

CuviStatus trackFeatures(const CuviImage& previous, const CuviImage& next, CuviPointValue2D<Cuvi32f,Cuvi32f>* inputFeatures, CuviPointValue2D<Cuvi32f,Cuvi32f>*& trackedFeatures, const Cuvi32s featureCount, CuviTrackingCriteria criteria, const CuviStream& stream = CuviStream());

Parameters

Name	Type	Description
previous	const CuviImage&	The first image whose features are to be tracked
next	const CuviImage&	Second image, in which to look for features of first image
inputFeatures	CuviPointValue2D<Cuvi32f,Cuvi32f>*	Feature of first image
trackedFeatures	CuviPointValue2D<Cuvi32f,Cuvi32f>*&	Output feature list containing the location of tracked features from first image onto second image
featureCount	const Cuvi32s	Number of features to track
criteria	CuviFeaturesCriteria	A structure containing various parameters that affect feature tracking behavior
stream	const CuviStream&	GPU stream ID for execution

Image Type Support

Input	Output
8uC1	CuviPointValue2D

Samples

Example

//Image size CuviSize size = cuviSize(img1->width,img1->height); //Create two 8-bit Grays-scale CuviImage objects CuviImage gimg1 = cuvi::io::loadImage(path, CUVI_LOAD_IMAGE_GRAYSCALE); CuviImage gimg2 = cuvi::io::loadImage(path, CUVI_LOAD_IMAGE_GRAYSCALE); CuviPointValue2D* features1, *features2; //selection and tracking criteria CuviFeaturesCriteria fc(CUVI_FEATURES_HARRIS,0.006f,22); CuviTrackingCriteria tc(2,CuviSize(12,12),15,10.0f); //ROI for selection CuviRect roi(0,0,gimg1.width(),gimg1.height()); int featureCount = 50; //Select Features cuvi::computerVision::goodFeaturesToTrack(gimg1,roi,features1,featureCount,fc); //Track the selected features from first frame onto second frame cuvi::computerVision::trackFeatures(gimg1,gimg2,features1,features2,featureCount,tc);