Top "Opticalflow" questions

Optical flow or optic flow is the pattern of apparent motion of objects, surfaces, and edges in a visual scene caused by the relative motion between an observer (an eye or a camera) and the scene.

What is the difference between sparse and dense optical flow?

Lots of resources say that there are two types optical flow algorithms. And Lucas-Kanade is a sparse technique, but I …

image-processing computer-vision opticalflow
How does KLT work in OpenCV?

I am curious about the logic behind KLT in openCV. From what I have known so far, the images sent …

opencv computer-vision tracking opticalflow
Optical Flow using OpenCV - Horizontal and Vertical Components

I have the following code that finds the Optical Flow of 2 images (or 2 frames of a video) and it's colour …

python opencv image-processing video-processing opticalflow
OpenCV's calcOpticalFlowPyrLK throws exception

I have been trying to form a small optical flow example with OpenCV for a while now. Everything works except …

c++ opencv assertions opticalflow
cv::goodFeaturesToTrack doesn't return any features

I'm trying to use cv::calcOpticalFlowPyrLK but sometimes an internal assertion in that function fails. The assertion is npoints = prevPtsMat.…

c++ opencv computer-vision opticalflow
OpenCV 2.4.2 calcOpticalFlowPyrLK doesn't find any points

I am using OpenCV 2.4.2 on Linux. I am writing in C++. I want to track simple objects (e.g. black …

c++ linux opencv opticalflow
How to implement Optical Flow tracker?

I'm using the OpenCV wrapper - Emgu CV, and I'm trying to implement a motion tracker using Optical Flow, but …

c# opencv computer-vision emgucv opticalflow
Fast, very lightweight algorithm for camera motion detection?

I'm working on an augmented reality app for iPhone that involves a very processor-intensive object recognition algorithm (pushing the CPU …

iphone opencv augmented-reality opticalflow
data type errors for input images of cv2.calcOpticalFlowPyrLK

I'm running opencv 2.4.1 using python bindings and am having difficulty calculating the optical flow. Specifically this section of code: #calculate …

python opencv opticalflow
Moving background subtraction (OpenCV)

Do you know any sources with background subtraction from moving camera? I want to write something similar to this: http://…

c++ opencv background-subtraction opticalflow