Creating animated medical images (Part 2)

With the advent of the Internet and World Wide Web (WWW), different image format became available. Some were static (GIF, JPEG) while others are animated (animated GIF, MPEG, Shockwave). Each carries distinct advantages for a given need and purpose, particularly for efficient transmission over the network. For instance, a GIF file is highly suitable for encoding diagram-like images – images that consist of line art and flat colour, whereas a JPEG is the chosen format for encoding images with photographic quality [1]. In encoding animated images, an animated GIF would be the chosen format for encoding a simple animation generated by a sequence of vector graphics while an MPEG format is preferred if animation with a movie-like quality is desired. Both these formats employ different algorithms to achieve the best animation quality at the optimal file size for network transmission [2]. Although the initial objective of developing the network, which later formed the framework for today’s Internet, was military in nature, the interconnectivity of these vast computing resources promises to be of much use for general users as well [3]. One of the driving factors behind the development of various applications and protocols, including the WWW, is the possibility of unlimited sharing of resources. The progress of the WWW has spawned a myriad of applications in numerous areas, be it for educational, research, or recreational purposes [4]. For instance, in the area of medical education the use of animation as a teaching tool has been proven to be one of the most effective methods in delivering learning materials [5,6]. Just by having a web browser, which incidentally can be acquired free of charge, the advantages of learning via animation may be shared with a large number of users. This tutorial will try to document a few simple steps involved in producing animated images from a series of medical images, using widely available software. The image samples (in both GIF and JPEG formats) from a computed tomography (CT) study are also available for download.