A - - #8 bit, Byte, Yutaka Yasuda
1/2 0/1 CD 9 1 0 0 or 1 1/9
4,3,4,7,7,8,8,5,3,2,2 4,3,4,7,7,8,8,5,3,2,2 4,3,4,7,7,8,8,5,3,2,2 4,3,4,7,7,8,8,5,3,2,2 CD/CD-R CD / CD-R
- 1 bit data (7bit) P 0 1 1 0 1 0 1 0... 1 bit 2 bit CRC Cyclic Redundancy Check
ECC Error Correcting Code 64bit 8bit ECC 1bit 2bit CIRC : CD *ECC Error check and correct memory
CD/CD-R CD / CD-R / ipod / SD ipod
Hardware Hardware Software data media data media
Hardware Software Format data media
Hardware MP3 Format Hardware CD audio Format Hardware MPEG Format MP3 music SD card MP3 CD audio CD CD MPEG2 video DVD DVD
PC : MP3 Format Hardware OS (system software) CD audio Format MPEG Format MP3 music SD card MP3 CD audio CD CD MPEG2 video DVD DVD
Windows Windows Media Player MP3 MPEG Hardware Microsoft Windows MS Word Word fmt. MS Excel Excel fmt. Adobe Reader PDF fmt. MP3 music MPEG2 video Word Excel PDF USB DVD MP3 DVD PDF
Web MP3 Web (Internet Explorer, Firefox, etc.) MPEG Hardware OS (system software) HTML JPEG PDF MP3 music MPEG2 video JPEG PDF Internet ( ) PDF
(generic) (specific)
online Local application(s) Web browser
Web Client Server Web browser Photoshop Express
vs Web Local application(s) data... Web browser Photoshop Express
vs Web Web Web ( ) Web ( ) JavaScript
Web only OS MP3 Web (Internet Explorer, Firefox, etc.) MPEG Hardware OS (system software) HTML JPEG PDF MP3 music MPEG2 video JPEG PDF Internet ( ) PDF
Web Client HTML GIF, JPEG, PNG, MPEG, H.264, AIFF, WAV Server JavaScript + DOM, etc. etc.. Web browser Photoshop Express Firefox Safari Chrome Internet Explorer
HTML5 の動画フォーマット Brendan Eich JavaScript の開発者 Mozilla で長くブラウザ開発 現在も Firefox を開発 2008 取材 データを棺桶に入れるな フォーマットはまだいい 問題はロイヤリティだ
HTML5 Ogg/Theora Mozilla (Firefox) : Ogg/Theora H.264 Apple : Ogg/Theora H.264 Microsoft (IE) : no comment H.264 Google (Chrome) : Ogg/Theora H.264 HTML5 2010/2 Google On2 Technologies On2 Ogg VP3 VP8
WebM On2 Technologies Google Google 2010 5 Google I/O VP8 + Vorbis
MPEG LA H.264 Ogg Theora VP8
Forgent JPEG JPEG 1987 Forgent Networks 2002 Forgent SONY 1500 2004 31 2006 Forgent
Unisys GIF (LZW) GIF 1987 Unisys 1985 LZW (Lempel Ziv Welch) 1996 GIF LZW 2003 2004
MPEG LA vs Google H.264 WebM 2010 8 MPEG LA H.264 WebM 2011 2 MPEG LA VP8 VP8 2011 4 Google WebM CCL
Google YouTube WebM H.264 Chrome VP8 VP8 MPEG LA Google 2011/2/18 http://techon.nikkeibp.co.jp/article/topcol/20110218/189700/
HTML5 HTML5 Google / WebM VP8 On2 Ogg Theora