November 15, 2009, 9:49 pm
A palindromic prime (palprime) is a prime number that is also palindromic. So out of curiosity I wrote a simple program a few days ago that can find the palindromic numbers within a given range. Here is the code in C++: Continue reading ‘A Simple Program for Finding Palindromic Prime Numbers’ »
July 3, 2009, 9:06 pm
In my previous three articles (1,2,3) I discussed how to use Canny edge detection and Hough transform to identify blur images. Here I will show some results from the algorithm discussed before. Continue reading ‘Image Blur Detection via Hough Transform — IV’ »
June 27, 2009, 9:31 pm
I will continue where I left off in my previous post. After performing Hough transform, and extracted the longest sections of lines for each corresponding Hough line detected, we will need to calculate the gradients of the image pixels luminance around the line sections. Continue reading ‘Image Blur Detection via Hough Transform — III’ »
June 24, 2009, 9:44 pm
In my previous post, I briefly discussed the rationale behind automated blur detection in digital imagery and did an overview of an algorithm that could be used to detect blur images. Here I will show some implementation details along with some C++ code snippets. Continue reading ‘Image Blur Detection via Hough Transform — II’ »
June 19, 2009, 10:41 pm
It is often necessary to identify and classify images based on their clarities. For instance, it is desirable for an automated process to locate blurred images within a large digitized image library and then automatically sharpen the blurred images via inverse filtering or blind deconvolution. In the following series of articles, I will discuss a practical method in detecting blur images using Hough Transform. Continue reading ‘Image Blur Detection via Hough Transform — I’ »
June 12, 2009, 5:55 pm
I was trying to search for some code examples on how to do a recursive directory search under Linux using C++ the other day. But to my surprise, I could not find any place that offers a complete example. So I decided to post my code here after I created my own and hopefully you will find it helpful. Continue reading ‘C++ Recursive Directory Search Under Linux’ »
May 28, 2009, 9:23 pm
Measuring the execution time for code sections can be done in multiple ways in C++. Except for the time resolution issue, different timing methods worked relatively the same in single processor environment. As multi-core processors become more prevalent however, we need to be careful at choosing the correct timing mechanism as not all such routines measure the wall time elapsed. Continue reading ‘Timing Methods in C++ Under Linux’ »
May 20, 2009, 8:24 pm
As I wrote last time, I did a clean Ubuntu 9.04 install on my main PC. Continue reading ‘Magick++ Missing Delegate Error’ »
May 7, 2009, 10:15 pm
In the example I gave in “Interfacing IPP with Magick++“, I illustrated how to use Intel’s Integrated Performance Primitives (IPP) to perform edge detection. One issue with Canny edge detection algorithm is that we need to specify a high threshold and a low threshold. How to select those threshold values affect the quality of the detected edge greatly. And in my previous example, the threshold values were chosen manually. In this blog post, I will examine a couple of simple methods that can be used to automatically determine the threshold values. Continue reading ‘Canny Edge Detection Auto Thresholding’ »
April 18, 2009, 10:27 pm
So far I have been mainly using KDevelop and Code::Blocks as my C++ development IDEs. Recently, I started using NetBeans IDE for C++ and I started to like it quite a bit. Continue reading ‘C++ IDEs Under Linux’ »
April 10, 2009, 8:34 pm
A couple of weeks ago, I wrote about how to interface Integrated Performance Primitives (IPP) with Magick++. While IPP offers excellent performance advantages, it does not come with the easiest programming model. Fortunately, it is easy enough to create a C++ wrapper on top of IPP and provide an easier to use programming interface. Continue reading ‘An Image Class Based On IPP’ »
March 17, 2009, 9:01 pm
Intel’s Integrated Performance Primitives (IPP) is a low level C++ library. It provides routines that are highly optimized on Intel processors. I recently started using it because its vast speed advantage in signal and image processing applications. Continue reading ‘Interfacing IPP with Magick++’ »