Calculating scale, rotation and translation from Homography matrix

c++ opencv video matrix homography
Lakshya Kejriwal picture Lakshya Kejriwal · Sep 4, 2014 · Viewed 26.2k times · Source

I am trying to calculate scale, rotation and translation between two consecutive frames of a video. So basically I matched keypoints and then used opencv function findHomography() to calculate the homography matrix.
homography = findHomography(feature1 , feature2 , CV_RANSAC); //feature1 and feature2 are matched keypoints

My question is: How can I use this matrix to calculate scale, rotation and translation?.
Can anyone provide me the code or explanation as to how to do it?

Answer

Vineet picture Vineet · Mar 28, 2015

if you can use opencv 3.0, this decomposition method is available http://docs.opencv.org/3.0-beta/modules/calib3d/doc/camera_calibration_and_3d_reconstruction.html#decomposehomographymat

Related questions

OpenCV - how to capture rtsp video stream

for example we have working rtsp stream test like: "rtsp://184.72.239.149/vod/mp4:BigBuckBunny_115k.mov" (it works in moment of publishing this post) Now I want to catch this video stream in openCV (opencv 2.4.7 / 2.4.8) I've my code works perfectly on …

Read More
How to open a GStreamer pipeline from OpenCV with VideoWriter

I am capturing video frames with OpenCV VideoCapture. The capturing works fine as I am able to use the frames like this: cv::VideoCapture cap("v4l2src device=/dev/video1 ! videoscale ! videorate ! video/x-raw, width=640, height=360, framerate=30/1 ! videoconvert ! appsink"); …

Read More
openCV: How to split a video into image sequence?

Using opencv, how can one split a video into an image sequence? How can i split it so that the output will be a sequence of images?

Read More