Science

sepdek October 8, 2016

Formally stated, the derivative of a function of the form with k a constant and with respect to an independent variable x, is simply, I find this to be extremely handy in all cases. Consider the simple case in which, In the same way, In a more complex example, In an even more complex example, […]

sepdek October 8, 2016

The thing starts with invariance, conservation and symmetry… Invariant is something that is unchanged by a coordinate transformation. Conserved is something that is unchanged by a process within a given coordinate system. Symmetry could be considered a broader property of some ‘universe’ in which some entity of interest remains the same under a specific operation. […]

sepdek October 8, 2016

In order to be a measure (distance) d must:   In order to be a metric (distance) d has to be a measure and:   …and here is the cheat sheet:  

sepdek July 17, 2015

DIGITAL TECHNOLOGIES IN CULTURAL HERITAGE & TOURISM 11 Days equivalent workload to 130 hours (incl. 20 hours essay), 5 ECTS 30 July – 10 August 2015 Delphi, Greece Complete summer school programme. COURSE: Introduction, current state-of-the-art, innovation, trends UNIT: Innovative applications of technology in cultural heritage and trends for future research and development PDF edition […]

sepdek May 15, 2014

It has been many years working on digitization, reconstruction and virtual world applications; tested and used various techniques covering almost all aspects in the digital recording workflow. In the recent past years our team has been successfully engaged in a very productive workflow regarding digitization and reconstruction in 3D. Specifically, this workflow involved the application […]

sepdek March 14, 2014

A straightforward approach to do geometric image transformations using MATLAB is to take advantage of the imtransform function available. First the image is supposed to be within a ‘unity’ rectangle and initial transformation conditions are defined accordingly: udata = [0 1]; vdata = [0 1]; fill_color = 128; org_rect = [0 0;1 0;1 1;0 1]; […]

sepdek February 16, 2014

Recently I read an interesting book “The Grand Design” by Stephen Hawking and Leonard Mlodinow. Somewhere at the end of the book there was a reference to the well known game of life by John Conway (1970). Although I knew it was implemented by various researchers and is already available in MATLAB with a demo […]

sepdek February 10, 2014

In a recently posted question @StackOverflow a user asked how to find the maximum Euclidean distance in a binary image produced by Canny edge detection using MATLAB. The original post is here. I report my response here just for archival purposes. Provided that you have a binary edge image, you need to think of white […]

sepdek December 30, 2013

Just a few days ago I run into a very interesting image processing challenge at StackOverflow. The challenge focused on the detection of a christmas tree in an image (see here for more info). Since I had a some free time I though I could give it a try… The rules in this challenge were […]