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Explore the significance of video compression in advancing the internet, the evolution of compression technology, understanding codecs, flash video importance, encoding video, and future trends in GPU-based encoding. Learn about different codecs, the benefits of compression, and the impact on online content delivery.
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Video Compression and the Internet
Need for Compression • Important to advancement of internet • Video prevalent all over the net • Compression has improved greatly over the past 10 years • Helped revolutionize the way internet delivers content
How it works • Exploits flaw in human perception • Algorithms written to do this • Areas of similar color averaged out • Image is the same over period of time • All works to make files smaller, with better quality • Allowing faster transmission online • Able to fit onto ipods, phones, etc
What is a codec? • Allows for the compression (co), and decompression (dec) of a video file • Represents analog information in a digital way • Bitrate – amount of data per second required • Lower is better
List of codecs through the years • MPEG1 • MPEG2 • Sorenson • Realplayer • Quicktime • DivX • XviD • H.264/x264 • VC-1
Importance of flash • Allowed sites like Youtube to flourish • Unified the standard of how to deliver video • Prior to flash video, different standards, confusing • Including Windows Media player, Quicktime, Realplayer and more • Everybody already has flash, so no ambiguity
The flash video format • Flv files embedded in websites • Contain video files • H.264, VP6, Sorenson H.263 • Previous flash versions starting at 6 supported different formats
Why encode video • Too large to upload to YouTube • 1gb file limit • Most digital cameras use poor codecs with little to no compression, wasting hard drive space, also making sending over internet unfeasible • Rip your dvds to your computer • Digitalize old home movies on analog sources for preservation and sharing online • To put on your portable media player (ipod) • Use of filters to improve video quality from bad sources
What does it take to encode video? • Choose a codec • h.264/x264 and xvid are common • A video file • An encoder • FFMpeg, MeGUI, Handbrake
What’s next • GPU based encoding • Badaboom • Uses Nvidia graphics cards • Faster than CPU • Quality an issue currently
Further Information • www.doom9.org • www.videohelp.com
Sources • http://www.doom9.org/index.html?/gknot-main6.htm • http://www.animemusicvideos.org/guides/avtech/video4_2.htm#Interesting • http://www.adobe.com/devnet/flv/pdf/video_file_format_spec_v10.pdf • http://www.kaourantin.net/2007/08/what-just-happened-to-video-on-web_20.html • http://www.maximumpc.com/article/features/is_era_gpubased_computing_really_upon_us • http://www.anandtech.com/video/showdoc.aspx?i=3339&p=2