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Basic cell counting and segmentation in Matlab

Counting cells manually is a tedious error prone process for humans. Given a large data set of microscopy images this task can be achieved much faster by means of basic computer vision techniques. In this tutorial we will segment cells from an image following a method similar to the one presented by Yongming Chen in 1999. The method uses basic morphological operations  and the watershed algorithm to segment the cells. Nowadays better methods for cell segmentation exist. This method was chosen for its simplicity and ease of implementation. We start with an image of cell-like structures by Anna-Katerina Hadjantonakis and Virginia E Papaioannou . A = imread('cells.jpg'); We convert the image to grayscale: I = rgb2gray(A); To be able to extract the dimmer cells, it is necessary to perform some local contrast adjustments I = adapthisteq(I); Objects on the borders can be caused by noise and other artifacts. We can eliminate objects on the borders...

A more confusing Internet with .brand TLDs

A few months ago, I wrote a post proposing to remove top level domains from the internet, as many people don't understand why we need TLDs. At the time I didn't know either. Removing TLDs would simplify browsing an possibly increase security by reducing phishing sites that make use of URL similarity to gain visits to potentially dangerous websites, or sites filled with ads. The ICANN, the body that manages Internet names, has for years been preparing something different but that produces a slightly similar effect than removing TLDs: allowing brands to register their own TLDs . The proposal may soon be approved has been approved . Brands would therefore be able to register their own TLDs. Google could register .google a potentially powerful TLD for their services, like Google Maps: maps.google instead of maps.google.com. Brand TLD don't improve short urls like google.com, but seem to be effective for use in subdomains. Registering a .<brand-name> TLD will cost...

Martha Graham's Google doodle is not a video, is an image (a CSS sprite)

Today's Google doodle is featuring Martha Graham, an American modern dancer. The new doodle looks like a movie, but in fact it is only a CSS sprite. The sprite is this one:  You may be wondering how is the animation/movie appearance achieved if it only uses this static image?  The technique involves CSS sprites. A sprite is a composition of several images grouped together in order to reduce the number of required HTTP request to the server. This way a website with 50 images requires only one request for the large image composition. The entire doodle involves only one sprite, which speeds up loading a lot (compared to loading each frame separately). Google has used this technique to leverage data transfer from the servers and consequently make the animation load faster than a traditional video clip.  So how is this sprite converted to an animation? Pretend you are looking through pierced piece of paper, so that you can only look through th...

Weekend project: Book's I've read

It's been months since I wanted to learn databases and create a dynamic website, but it's only this weekend that I acted. In two day I learned how to use MySQL with PHP in websites and created a small project that I call "Books I've read" that stores a list of books I read (obviously). I am an avid reader and I've been storing the list of books I read (and want to read) in a text document for about a year. Finally, my project moved this list to the cloud and allows me to add, edit and update entries. The app has user authentication, so no one except me can alter my book list. The design was made in a hurry, but is good enough for my needs. Instead of using normal CSS for styling I've used LESS CSS, a dynamic stylesheet language that extends CSS with dynamic behavior, nested rules, mixins and logical operators. LESS CSS has made styling faster, but unfortunately it relies on Javascript. Without Javascript activated the website breaks. And t...

Website complete: presojaidej.com

Presojaidej.com is a service that offers reviews of ideas for a competitive price. This being one of my first websites I developed I want to explain my workflow and reasoning while creating it. Dislaimer: I am only the developer and designer of the website; it is owned by E-amiga, d.o.o. I was given a lot of freedom regarding the look of the website, so it was an enjoying small project. The only guideline I was given is the general form: the client wanted it to be on one page, so that there are fewer clicks required by the user to order a business idea review. I wanted to create a website that looked professional and had a large conversion rate (the percentage of users that order the service after visiting the website). The professional look was achieved with clear lines, and attention to detail: the background patterns, the differences in border colors to imitate slight depth and a snappy feeling on hovering over the buttons among others. The resulting page is easy to scan throug...

The Increased Addictiveness of Today's Video Games

This is a guest post by Miles Walker, a freelance writer and blogger who usually  compares car insurance  deals over at CarinsuranceComparison.Org. His most recent review looked at the best  car insurance quotes . Video games have always held some addiction, but now more than ever that addiction is growing. People are spending more time than ever playing the games, and game designers are constantly finding new ways keep it that way. Their efforts have a been a complete success, and some games have true addicts, addicts who play 24 hours a week or more. Visual enhancements Video games have come a long way since a certain duo of Italian plumbers started showing up in people's houses in the late 1980s. By leaps and bounds, video game graphics have become alarmingly sophisticated. Each graphical improvement increased a game's possibilities and added more depth to video games. Designers began thriving on this depth, making games with more achievements, unlocks, lev...

One language will be enough.

A few weeks ago Google released a tool that provides voice translation into several languages for free. This is a major breakthrough in democratizing voice translation technology that could bring us to an era where knowledge of foreign languages looses its importance. This is a bold statement, but I think it will happen in a few decades or maybe years. Nowadays fluency in several languages is important for several reasons including applying for a job, communicating with foreigners, travelling, education (especially for countries that don't publish enough books in their own language), accessing the internet and online resources and much more. In exception of some businesses and institutions that depend of high quality formal translations the wording required to understand a foreign text is relatively small. Most humans are not very dependent on high quality translations. For example, a tourist doesn't need to master the language of the country he's visiting, nor does an ...