The World Wide Web was started as a means to share information amongst academics. While the original Web shared mostly text, the sharing of images came from the very roots of the World Wide Web. The original proposal of the HTML drafted in 1993 included the img tag that embeds images on the web page itself. From this basic lineage, photo sharing has become one of the most popular web services on the Internet as it became more commercial and mainstream.
In this chapter we will be creating a clone of Flickr, one of the most popular photo-sharing services around. We will start with a discussion on photo-sharing applications and then move on to the main features that make up such an application. After that we will proceed to design the application then show how it can be coded using the same technology stack we used in the previous chapters.
Photo sharing is one of the most popular services on the Internet and also one of its most useful services. Basically, photo sharing is about the uploading of digital photos by a user, to be shared with others either publicly or privately. The first photo-sharing applications appeared during the time when the World Wide Web itself was in its infancy, during the mid 1990s, but it was only after the dot-com bust that many of the current crop of photo-sharing applications started. One of the earliest photo-sharing applications is Webshots, which originated from a desktop screensaver software in 1995 and eventually migrated to the World Wide Web. Other popular photo-sharing services include Flickr, Photobucket, ImageShack, SmugMug, Snapfish, and Picasa, Google's photo-sharing service. In the past few years astonishingly (yet perhaps not) an entrant to the photo-sharing market is Facebook. As of writing, Facebook users upload an average of 3 billion photos every month and it is one of the largest photo-sharing applications around, despite being a new entrant.
Photo sharing as a market is pretty diverse and almost every one of the photo-sharing applications has its own signature strengths and focuses, so direct comparison is often meaningless. For example, while Facebook has many billions of images more than Flickr, its main premise is social networking while Flickr's main motivation is photo-sharing and social interaction through photos. As a result, Facebook doesn't allow sharing photos outside of Facebook users, and resizes all photos that are uploaded while Flickr allows anonymous sharing and viewing of photos and also maintains multiple sizes of the uploaded photo, including the original.
However, a good snapshot of popularity is through gauging the number of unique users of the service. We use Compete (http://www.compete.com) to analyse the number of users to the various popular photo-sharing applications. Note that we did not include Facebook in this comparison because it is impossible (without internal Facebook information) to determine from Compete the number of unique visitors to Facebook photos since they use a full URL to access their photo pages rather than a more general domain (such as http://www.flickr.com) or subdomain (such as http://picasa.google.com).
As we can see, Flickr ran closely with Photobucket for the honor of most popular photo-sharing application though for the past year or so, Photobucket seems to have fallen behind in the race. In this chapter we will be focusing on Flickr, one of the most popular and widely known photo-sharing applications around.
Flickr was launched in February 2004 by Ludicorp, a Vancouver-based company. Flickr was originally created for Ludicorp's Game Neverending, a web-based massively multiplayer online game, but it became the main focus after the original project was shelved. In March 2005, Yahoo! acquired Ludicorp and Flickr and all content was migrated from servers in Canada to servers in the United States. On April 9, 2008, Flickr began to allow paid subscribers to upload videos, limited to 90 seconds in length and 150 MB in size. On March 2, 2009, Flickr added the ability to upload and view HD videos, and began allowing free users to upload normal-resolution video.
Flickr offers two types of accounts: Free and Pro. Free account users are allowed to upload 100 MB of images a month and two videos. If a free user has more than 200 photos on the site, they will only be able to see the most recent 200 in their photostream, though the photos uploaded are still there. Pro accounts allow users to upload an unlimited number of images and videos every month and receive unlimited bandwidth and storage.
Flickr uses tags to organize images and also sets, which are convenient categories that a photo can belong to. Sets may be grouped into collections, which can be nested. Photos in Flickr can be private to the user, private to family and friends or public to everyone, including anonymous viewers.
One of Flickr's stronger points is in the management of the copyright of the photos uploaded by its users. While many photo-sharing applications have little to no capabilities to manage the copyright of the uploaded photos, Flickr provides a friendly guide to both uploaders and viewers of photos to its site. Uploaders can choose copyright licenses that range from 'all rights reserved' to various combinations of Creative Commons licensing. As a result uploaders can choose to share their photos with various licences that are more assuring to viewers who fear that their activities might infringe any copyright materials.
Flickr focuses a lot on, and is very strong with, the user community. The social aspects of the site are probably the key features of Flickr. In fact, Flickr, at a certain level, can be considered as a social network that focuses on photos. Several features support this. Flickr has a concept of a photostream, which is a list of recent photos that have been uploaded and published to the site. Photostreams implies a need to continually take and upload photos and brings the sense of a photo blog to the site. In this sense, Flickr was designed to reward recent activity, something that is in line with the more recent social networks and microblogs such as Facebook and Twitter.