You are probably searching for the function resize(), see here.
I would suggest using the properties of the region of interest parameter, before the step of resizing.
Some sample code which will guide you:
Mat original; imread('location', original);
//use info to calculate your roi based on current location of mouse pointer
Rect roi(0,0,50,50);
Mat temp = original(roi);
imshow('temp', temp);
Mat is actually the C++ variant of the C-style IplImage.
Take a look at the tutorials of OpenCV or read the newly released book. Especially the last one is interesting if you have no OpenCV background.
See I have few questions and confusions. I want you to clear it out. I want to do live zooming(in and out) not "video zooming". and how can we set zooming parameter. I ran this code "http://answers.opencv.org/question/10291/syntax-for-zooming-a-video/" but it is getting too much zoomed. i don't know which parameter is affecting, this zooming. is there any way to make me understand this code which is in link? so that my understanding get better. And what if we want to do live zooming with usb web cam(logitech). what i have to read and understand for that.
I will take a look at your comment in about an hour, be patient and please do not open new topics for the same problem.
Basically you need to be sure that you actually want to perform software zooming? Probably your logitech USB webcam has an available API which can be accessed in C++ to call the zooming of the camera itself. Wouldn't that be more interesting?
This http://www.quickcamteam.net/documentation/faq/can-i-use-logitech-webcams-for-my-own-application">link probably tells you everything you should do :) Go give it a try! Or have a look at this link.
first link is not working. second link is not helpful. and yes i am using logitech camera. but you are not getting my question .. i just want to know how to implement zoom in and out in open cv.. and i am using code blocks to program it all.how to superimpose one image to whole screen.how to zoom in and out by camera in open cv. are there any predefined functions for this.
Asked: 2013-07-09 08:04:59 -0600
Seen: 15,383 times
Last updated: Jul 10 '13
