OpenCV Q&A Forum - RSS feedhttp://answers.opencv.org/questions/OpenCV answersenCopyright <a href="http://www.opencv.org">OpenCV foundation</a>, 2012-2018.Sun, 06 Jul 2014 10:36:08 -0500Deconvolution - Theoryhttp://answers.opencv.org/question/36386/deconvolution-theory/Hello,
just a quick question about theory: I'm studying deconvolution, specifically, image restoration.
Briefly, we want to calculate an image estimate F_est of the original, unblurred, image f by minimizing:
2
T = || I_out - K*f ||
2
I_out = our output, blurred image
K = point spread function
T measures how close our current estimate is to I_out and we aim at minimize this distance. My question is: if the current estimate is very close to I_out, what does that indicate, why is that a good estimate? What if they would be distant?
Thanks in advance!
JoeMamaSun, 06 Jul 2014 10:36:08 -0500http://answers.opencv.org/question/36386/Digital Image Gradienthttp://answers.opencv.org/question/25114/digital-image-gradient/Greetings .
I want to implement the Fast Radial Symmetry Transform (described here http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.97.4064&rep=rep1&type=pdf) to identify nuclei of cells in histological images of breast cancer for this I need to first calculate the gradient of the image. Until now he had not reviewed very afond what the gradient of a digital image is itself. Now I have several questions I would like to clarify:
(1) According understand the gradient of each point of a function is a vector formed by the partial derivatives of each variable, so for a digital image (which is a discretization of a 2D function) the gradient at each point in the image? which is exactly?. I guess it should be a two-channel digital image or am I wrong?
(2) How I can calculate or approximate the gradient of an image?
(3) Is there a function in OpenCV to compute or approximate the gradient of an image?
Thanks in advance for any help and/or suggestions and I apologize if my questions seem silly or too elementary .isaacenriqueSun, 08 Dec 2013 00:58:55 -0600http://answers.opencv.org/question/25114/