The Basics

What is animation? Well, when a sequence of images are displayed one-by-one within a specified time, it is called animation. The eternally falling paratrooper to the right is an example of animation. He is made up of 6 images. Each of these image is called a frame. Animation files contain the frames, information regarding how each frame is to be displayed, the intervel in which these should be displayed, and the embeded sound if any. Thus, when you are working with animations, you have the power to change/create these data elements.

The Formats

There are many animation formats available - AVI, FLC, FLI, MPEG, MOV, etc.. But we will be discussing only those which are web-enabled, & these are:

• GIF - Graphic Interchange Format
• MOV - Quick Time Movie
• AVI - Audio Video Interleaved (Microsoft Video for Windows)
• MPEG I - Motion Picture Expert Group
• RealMedia Encoded Files

GIF

GIF has become the de facto standard for web animation. It's main features are:

• Supports transperency
• Can play a file in an unending loop
• Doesn't support sound
• Supports progressive downloads
• Frames cannot contain more than 256 colors

The popularity of GIF format comes from the fact that this format is universally supported by all graphical web-browsers. No additional plugin is needed for displaying animations in this format.

MOV

The Apple Quick Time Movie format has been around for a long time. This has been the favorite format of CD-ROM publishers. Now this format has been developed to support various web features like progressive downloads. The main reason for the success of this format is that it is supported equally well in a Mac system as well as in a PC. Even support for this format in Unix/Linux systems is extended with softwares like xanim. This format features good audio/video synchronization & support for various compression codecs. This format is best suited when you have to deliver professional quality video across the net.

AVI

AVI's claim to fame is that it was the format whose support was built into Windows95. But as with everything from Microsoft stable, this too was not a reliable format. Particularily, the audio-video synchronization is pitiable. Although videos in this format abound the web, it is better to avoid this format. Also Microsoft too has ducked this format for its new one: Active Streaming Format (ASF).

MPEG I

The best part of this format is that the compression achievied by this format is the best among all the others, without compromise on quality. But it doesn't support progressive downloads. For playing videos in this format, a fast processor is needed. This format is best for short good quality videos.

RealMedia

RealMedia encoded files are particularily made for the web. These files support true streaming & progressive downloads. And for this capability, it has a price - for true streaming you need to have Real server installed. But using this format you can protect your copyright - you can make the client see the video, but he will not be able to save it in his disk or transfer it to someone else.