| |
Using Images and Videos in Websites
Images
Images are the photographs, digital artwork, charts, etc, that you will use on your web site. Quick summary of the three image types found on the web:
- GIF - An older image format great for legacy compatibility web sites. Great for short, small animations, such as web advertisements. A decent choice for line art.
- JPEG - (Commonly labeled simply as JPG) This stands for Joint Photographic Experts Group, so, as you guessed, is typically used with photographs, as well as complicated artwork and three-dimensional renderings.
- PNG - This format is now in widespread use across the web, and actually handles both simple artwork -and- photographs fairly well.
So, imagine you have a photograph from your digital camera. It's probably saved in JPG format. But the level of clarity in that photograph is probably made for printing the picture, and holds too much detail for a web site, resulting in lengthy Internet transfer times.
Video
Just as with photographs, the AVI file that your digital camera takes is probably not the best format for web usage. Here are some of the major players:
- MOV - Apple's Free QuickTime Movie Player on Windows and Mac computers uses this format, which allows for many picture quality settings and audio quality options. QuickTime comes pre-installed on Macs, and can be installed free from Apple from its web site or may already be installed if you use iTunes for Windows. Check out QuickTime movies in action on the Apple New Movie Trailers web site.
- Windows Media Player - Windows Media Player has a lot of different file options just as QuickTime does. Here's a list of some of them. (The AVI format your camera may save to falls under this format category.)
http://support.microsoft.com/kb/316992
Many Windows Media files can be played on a Mac, too:
http://www.microsoft.com/windows/windowsmedia/player/wmcomponents.mspx
- FLV - Flash's Video Format - This allows videos to be played by web visitors using recent versions of Adobe's Flash Player without any extra downloads.
Video Compression
Videos should be compressed before placing them onto a web site. As of writing (2009), it's best to keep videos to under about five minutes in length.
A two-hour DVD can easily take up to 5GB (5,000+ MB) of disk space, but compressed to some advanced formats such as MPEG-4, it can fit into under 0.7GB (+/- 700 MB), allowing a two-hour DVD movie to fit on a single burned CD. These advanced formats are what make online movie rentals and downloads possible. The quality is great, but downloading the movie takes significantly less time (although still measured in minutes even on fast broadband connections, not the seconds most people dream of).
back to website development guide
|
|
|
|
