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WebRTC experiment - Recognizing hand gestures

I have created a web application that recognizes hand gestures using WebRTC's getUserMedia API. Here's how it works: when you launch the application the browser will prompt you for the permission to access the camera. Click on 'Accept',and then swipe your hand from right to left and vice versa. You would see that the next image  (or the previous image if you swipe from left to right) in the gallery slides through. You can access the application here . Please note, I have tested this application on Chrome only and not on other browsers. Also, I have used five images in this demo and it is obvious that no image would be shown if you swipe from right to left when the last image is being shown or when you swipe from left to right when the first image is shown. I have codenamed this application as 'Gesto' and hence the name in the URL of the application.

Client side MVC: Using Publisher - Subscriber event model to build decoupled components

I've been really busy these days writing client side MVC code. A few months back I explored using Require and Backbone to build the frontend MVC structure . Since then I've been working on improving the structure of my client side code. One approach that I've used is to decouple the components. When I say decouple, the components that I build should not directly alter or affect the behavior of some other component in the page. By decoupling the components, we can ensure that these set of components can be reused and tested in isolation.

Adding beforeRender and afterRender functions to a Backbone View

I was working on a Backbone application that updated the DOM when a response was received from the server. In a Backbone View, the initialize method would perform some operations and then call the render method to update the view. This worked fine, however there was scenario where in I wanted to perform some tasks before and after rendering the view. This can be considered as firing an event before and after the function had completed its execution. I found a very simple way to do this with Underscore's wrap method.

Some useful Underscore methods

I like jQuery and I use it in all my projects. Lately I've been looking into Design Patterns and Backbone framework. Backbone has a dependency on Underscore and more often than not, people use Underscore as a client-side templating engine when using Backbone. I was looking at the Underscore documentation and came across a bunch of useful methods.

Goodbye 2012

2012 has just gone by and all I can say is that, it has been yet another eventful year. The biggest thing that happened to me was my new job at Myntra. It has been two months since I joined my new employer and I'm liking my new work. I had started last year with a few goals (I don't like calling them as resolutions) and the very first one was to reduce weight. I had met with an accident in 2011 (a terrible one) and had to stay at home for two months. And by staying at home and munching all that good food, I had put on some extra weight and wanted to loose it desperately. I think I almost cleared that goal and now I'm proud of it.

Applying MVC to your frontend application using Require and Backbone

I've been looking into BackboneJS for quite sometime now and thought it would interesting to build an application using the MVC pattern. Although Backbone provides various components - Models, Collections, Routers and Views; it doesn't provide a framework that can help you to structure the application using these components. While working on this application, I realized that I can separate these components in such a way that they can be made reusable or rather loosely coupled by defining the components in separate files. However, there was an interesting problem that I came across where the Views had a dependency on the Collections to be loaded first and then render the template data. I had read a little about RequireJS that allowed modules to be loaded asynchronously and also in resolving dependency. Thought I would give it a try and see whether it addresses this problem.

Using Routers in Backbone.js

After taking a break for a few days and then joining my new employer, I'm writing this long pending post on Routers in Backbone. A Router can be considered as a Controller in a MVC application. Controller in any MVC application defines how the incoming request should be handled. For example, a Servlet in a J2EE application accepts the request and looks into the configuration and delegates the request to one of the handlers.