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‐ Can be either NTSC or PAL
CD‐ROM FORMATS
‐ Not so popular anymore because of the web
‐ Higher bandwidth than web video
‐ Capable of DVD quality on fast computers
INTERNET FORMATS
‐ Less bandwidth so every bit of data has to count
‐ Web video can use either real‐time streaming mode or progressive‐download mode
‐ Real‐time requires specialised streaming server software and are limited in quality by the bandwidth
available between the server and the end user.
‐ Progressive‐download files load from standard web servers, and may take a long time to download,
but may also provide higher and more reliable video and audio quality.
MOBILE DEVICES
‐ These devices have small screens and slow processors, even compared to a laptop computer, but the
ability to play video back on extremely small and lightweight devices can have great value.
‐ Most compressed video formats can be played on some mobile devices, including Adobe® Flash®
Video, MPEG‐4, Microsoft® Windows Media, and RealMedia. Dedicated mobile formats, like Kinoma,
are also available.
‐ There are no universal formats or settings for mobile devices. Instead, content has to be optimized
for a small class of devices or even a particular model. When the optimization is successful, the results
can be great.
The Fundamentals
HUMAN SENSES
‐ Limitations in our senses of sight and hearing make compression possible
‐ Compression technologies take advantage of the strengths and weaknesses of human senses by
reducing data that isn't likely to be perceived.
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