[B! ppm] mogwaingã®ãƒ–ãƒƒã‚¯ãƒžãƒ¼ã‚¯

mogwaing id:mogwaing

ppmã«é–¢ã™ã‚‹mogwaingã®ãƒ–ãƒƒã‚¯ãƒžãƒ¼ã‚¯ (7)

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mots quotidiens. - PPM, è¨€èªžãƒ¢ãƒ‡ãƒ«, Burrows-Wheeler Transform
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mogwaing 2009/09/02
ppm

bwt

to see
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ã‚µãƒ¼ãƒ“ã‚¹çµ‚äº†ã®ãŠçŸ¥ã‚‰ã›
ã‚µãƒ¼ãƒ“ã‚¹çµ‚äº†ã®ãŠçŸ¥ã‚‰ã› ã„ã¤ã‚‚Yahoo! JAPANã®ã‚µãƒ¼ãƒ“ã‚¹ã‚’ã”åˆ©ç”¨ã„ãŸã ãèª ã«ã‚ã‚ŠãŒã¨ã†ã”ã–ã„ã¾ã™ã€‚ ãŠå®¢æ§˜ãŒã‚¢ã‚¯ã‚»ã‚¹ã•ã‚ŒãŸã‚µãƒ¼ãƒ“ã‚¹ã¯æœ¬æ—¥ã¾ã§ã«ã‚µãƒ¼ãƒ“ã‚¹ã‚’çµ‚äº†ã„ãŸã—ã¾ã—ãŸã€‚ ä»Šå¾Œã¨ã‚‚Yahoo! JAPANã®ã‚µãƒ¼ãƒ“ã‚¹ã‚’ã”æ„›é¡§ãã ã•ã„ã¾ã™ã‚ˆã†ã€ã‚ˆã‚ã—ããŠé¡˜ã„ã„ãŸã—ã¾ã™ã€‚
mogwaing 2009/05/31
å‰ã®æ–‡å—ã‚’ç„¡è¦–ã—ã¦1æ–‡å—ã ã‘ã®ç¢ºçŽ‡ã‚’åˆ©ç”¨ã™ã‚‹ã®ã‚’ã‚ªãƒ¼ãƒ€ãƒ¼0ã¨ã„ã„ã¾ã™ã€‚

compression

ppm
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ã‚µãƒ¼ãƒ“ã‚¹çµ‚äº†ã®ãŠçŸ¥ã‚‰ã›
ã‚µãƒ¼ãƒ“ã‚¹çµ‚äº†ã®ãŠçŸ¥ã‚‰ã› ã„ã¤ã‚‚Yahoo! JAPANã®ã‚µãƒ¼ãƒ“ã‚¹ã‚’ã”åˆ©ç”¨ã„ãŸã ãèª ã«ã‚ã‚ŠãŒã¨ã†ã”ã–ã„ã¾ã™ã€‚ ãŠå®¢æ§˜ãŒã‚¢ã‚¯ã‚»ã‚¹ã•ã‚ŒãŸã‚µãƒ¼ãƒ“ã‚¹ã¯æœ¬æ—¥ã¾ã§ã«ã‚µãƒ¼ãƒ“ã‚¹ã‚’çµ‚äº†ã„ãŸã—ã¾ã—ãŸã€‚ ä»Šå¾Œã¨ã‚‚Yahoo! JAPANã®ã‚µãƒ¼ãƒ“ã‚¹ã‚’ã”æ„›é¡§ãã ã•ã„ã¾ã™ã‚ˆã†ã€ã‚ˆã‚ã—ããŠé¡˜ã„ã„ãŸã—ã¾ã™ã€‚
mogwaing 2009/05/25
compression

ppm
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ã‚µãƒ¼ãƒ“ã‚¹çµ‚äº†ã®ãŠçŸ¥ã‚‰ã›
ã‚µãƒ¼ãƒ“ã‚¹çµ‚äº†ã®ãŠçŸ¥ã‚‰ã› ã„ã¤ã‚‚Yahoo! JAPANã®ã‚µãƒ¼ãƒ“ã‚¹ã‚’ã”åˆ©ç”¨ã„ãŸã ãèª ã«ã‚ã‚ŠãŒã¨ã†ã”ã–ã„ã¾ã™ã€‚ ãŠå®¢æ§˜ãŒã‚¢ã‚¯ã‚»ã‚¹ã•ã‚ŒãŸã‚µãƒ¼ãƒ“ã‚¹ã¯æœ¬æ—¥ã¾ã§ã«ã‚µãƒ¼ãƒ“ã‚¹ã‚’çµ‚äº†ã„ãŸã—ã¾ã—ãŸã€‚ ä»Šå¾Œã¨ã‚‚Yahoo! JAPANã®ã‚µãƒ¼ãƒ“ã‚¹ã‚’ã”æ„›é¡§ãã ã•ã„ã¾ã™ã‚ˆã†ã€ã‚ˆã‚ã—ããŠé¡˜ã„ã„ãŸã—ã¾ã™ã€‚
mogwaing 2009/05/25
compression

ppm
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Prediction by Partial Matching - Wikipedia
Prediction by Partial Matching(PPM)ã¯1984å¹´ã«J.G.Clearyã¨I.H.Wittenã«ã‚ˆã£ã¦è€ƒæ¡ˆã•ã‚ŒãŸãƒ‡ãƒ¼ã‚¿åœ§ç¸®ã‚¢ãƒ«ã‚´ãƒªã‚ºãƒ ã®1ã¤ã€‚ ã“ã®æ”¹è‰¯ç‰ˆãŒ7-zipç‰ã«ç”¨ã„ã‚‰ã‚Œã¦ã„ã‚‹ã€‚éžå¸¸ã«é«˜ã„åœ§ç¸®çŽ‡ã®åé¢ã€åœ§ç¸®é€Ÿåº¦ã¯ã‹ãªã‚Šé…ããƒ¡ãƒ¢ãƒªã‚‚å¤šãæ¶ˆè²»ã™ã‚‹ã‚¢ãƒ«ã‚´ãƒªã‚ºãƒ ã§ã‚ã‚‹ã€‚ ã“ã®äºœç¨®ã¨ã—ã¦PPMCã€PPMdã€PPMZç‰ãŒã‚ã‚‹ã€‚ aabacaabbaã¨ãƒ‡ãƒ¼ã‚¿ã‚’ç¬¦å·åŒ–ã—ãŸã¨ã—ã¦ã€æ¬¡ã«ã©ã®è¨˜å·ãŒå‡ºç¾ã™ã‚‹ã‹ã‚’çµ±è¨ˆçš„ã«äºˆæ¸¬ã™ã‚‹ã€‚ ã“ã®å ´åˆã€çµ±è¨ˆçš„ã«aã®æ¬¡ã«ã¯aãŒå‡ºç¾ã™ã‚‹å¯èƒ½æ€§ãŒé«˜ã„ã€‚é€†ã«cãŒå‡ºç¾ã™ã‚‹å¯èƒ½æ€§ã¯ä½Žã„ã§ã‚ã‚ã†ã€‚ã“ã®ã‚ˆã†ã«å‡ºç¾ç¢ºçŽ‡ã«åã‚ŠãŒã‚ã‚‹ã¨ãƒãƒ•ãƒžãƒ³ç¬¦å·ã‚„ç®—è¡“ç¬¦å·ã§åœ§ç¸®ã™ã‚‹ã“ã¨ãŒå‡ºæ¥ã‚‹ã€‚ ã—ã‹ã—ã€ä¸Šè¨˜ã®å ´åˆã«æ¬¡ã«å‡ºç¾ã™ã‚‹ç¬¦å·ã‚’aã‚’50%ã€bã‚’40%ã€cã‚’10%ã¨äºˆæ¸¬ã—ãŸã¨ã™ã‚‹ã¨ã€ä»–ã®è¨˜å·ã¯çµ¶å¯¾ã«ç¾ã‚Œãªã„ã¨ã„ã†ã“ã¨ã«ãªã‚Šã€æ–°ãŸãªè¨˜å·(dã¨ã™ã‚‹)ãŒå‡ºç¾ã—ãŸã¨ãã«å¯¾å¿œ
mogwaing 2009/05/24
compression

ppm
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SP partial decodable compression
SPã¯Static PPMã‚’ç”¨ã„ãŸãƒ‡ãƒ¼ã‚¿åœ§ç¸®ãƒ—ãƒã‚°ãƒ©ãƒ ã§ã™ã€‚ å¾“æ¥ã®ãƒ‡ãƒ¼ã‚¿åœ§ç¸®æ³•ã¨æ¯”è¼ƒã—æ¬¡ã®ç‰¹å¾´ãŒã‚ã‚Šã¾ã™ã€‚ å…¨ä½“ã‚’å¾©å…ƒã›ãšã«ä»»æ„ã®éƒ¨åˆ†ã®ã¿ã‚’å¾©å…ƒå¯èƒ½ å¤§ãã„ãƒ•ã‚¡ã‚¤ãƒ«ã«å¯¾ã—ã¦åœ§ç¸®çŽ‡ã¯bzipã¨åŒç¨‹åº¦ã€‚å°ã•ã„ãƒ•ã‚¡ã‚¤ãƒ«ã§ã¯gzipã¨åŒç¨‹åº¦ã€‚ å¾©å…ƒå‡¦ç†ã®è¨ˆç®—é‡ã€é ˜åŸŸé‡ã¯å¾“æ¥ã®é«˜åœ§ç¸®çŽ‡ã®æ‰‹æ³•ï¼ˆBWTã‚„PPM)ã¨æ¯”è¼ƒã—ã¦å°ã•ã„ SPã¯ç ”ç©¶ç›®çš„ã«é–‹ç™ºã•ã‚ŒãŸãŸã‚ã€ä¸€èˆ¬çš„ãªåœ§ç¸®ã‚½ãƒ•ãƒˆã¨ã—ã¦ã®åˆ©ç”¨ã¯æƒ³å®šã—ã¦ã„ã¾ã›ã‚“ã€‚ãã®ãŸã‚ã€åœ§ç¸®ã—ãŸãƒ•ã‚¡ã‚¤ãƒ«ãŒå¾©å…ƒã§ããªã„å¯èƒ½æ€§ã‚„æœ€æ‚ªã®å ´åˆãƒ•ã‚¡ã‚¤ãƒ«ãŒæ¶ˆåŽ»ã•ã‚Œã‚‹å¯èƒ½æ€§ãŒã‚ã‚Šã¾ã™ã€‚æ±ºã—ã¦ç ”ç©¶ç›®çš„ä»¥å¤–ã§åˆ©ç”¨ã—ãªã„ã§ãã ã•ã„ã€‚æœ¬ãƒ—ãƒã‚°ãƒ©ãƒ (SP)ã‚’åˆ©ç”¨ã—ãŸã“ã¨ã«ã‚ˆã‚Šç”Ÿã˜ãŸã„ã‹ãªã‚‹æå®³ã«å¯¾ã—ã¦ã‚‚ä½œè€…ã¯è²¬ä»»ã‚’è² ã„ã¾ã›ã‚“ã€‚ã”äº†æ‰¿ãã ã•ã„ã€‚ ã¾ãŸã€ã‚½ãƒ¼ã‚¹ã‚³ãƒ¼ãƒ‰ã‚’ã‚³ãƒ³ãƒ‘ã‚¤ãƒ«ã—ã€å‹•ä½œã•ã›ãŸçµæžœã«å¯¾ã—ã¦ã‚‚ä½œè€…ã¯ä¸€åˆ‡è²¬ä»»è² ã„ã¾ã›ã‚“ã€‚ã‚½ãƒ¼ã‚¹ã‚³ãƒ¼ãƒ‰ã¯è‡ªç”±ã«æ”¹å¤‰ã€åˆ©ç”¨ã—ã¦ãã ã•ã£ã¦æ§‹ã„ã¾ã›ã‚“ã€‚å•†ç”¨åˆ©ç”¨
mogwaing 2009/05/20
static ppm

algorithm

compress

ppm
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PPM
PPMã¨ã¯ï¼Ÿ PPMã¨ã„ã†ã®ã¯ã€æ—¢å‡ºã—ãŸãƒ‡ãƒ¼ã‚¿ã‹ã‚‰æ¬¡ã®æ–‡å—ã‚’äºˆæ¸¬ã—ã¦ã€ç¢ºçŽ‡ã‚’å¤‰åŒ–ã•ã›ã‚‹ ã“ã¨ã«ã‚ˆã‚Šåœ§ç¸®ã™ã‚‹ã‚‚ã®ã§ã‚ã‚‹ã€‚ ä¾‹ãˆã°ã€€abcdabcdabcdabcâ—‹ ã¨æ¥ã¦â—‹ã«å…¥ã‚‹æ–‡å—ã¯ä½•ã ã‚ã†ã¨è€ƒãˆã¦ã¿ãŸã¨ãã€dãŒå‡ºã‚„ã™ã„ã¨ã„ã†ã®ã¯ç›´æ„Ÿçš„ã« ã‚ã‹ã‚‹ã€‚ãã†ã„ã†å ´åˆã¯dã®ç¢ºçŽ‡ã‚’ä¸Šã’ã€ä»–ã®æ–‡å—ã®å‡ºç¾ç¢ºçŽ‡ã‚’ä¸‹ã’ã‚‹ã€‚ã™ã‚‹ã¨ã€åœ§ç¸® ã•ã‚Œã‚‹ã€‚ãŸã¶ã‚“ã‚ã‹ã‚‰ãªã„ã¨æ€ã†ã®ã§ã€è©³ã—ãèª¬æ˜Žã—ã¾ã™ã€‚ ç¢ºçŽ‡ã‚’ä¸Šã’ã‚‹ã¨ãªãœåœ§ç¸®çŽ‡ãŒä¸ŠãŒã‚‹ã‹ï¼Ÿ ä¾‹ãˆã°ï¼˜ç¨®é¡žã®æ–‡å— a,b,c,d,e,f,g,hã€€ãŒã‚ã£ã¦ã€ãã‚Œã‚’0ã¨1ã§è¡¨ã™ã®ãªã‚‰ã° a:000 b:001 c:010 d:011 e:100 f:101 g:110 h:111 ï¼ˆæ–¹æ³•ï¼¡ï¼‰ ã¨ãã‚Œãžã‚Œã«3bitå‰²ã‚ŠæŒ¯ã‚Œã°ã‚ˆã„ã€‚ã¤ã¾ã‚Šä¸€æ–‡å—ã«ä»˜ã3bitä½¿ã†ã€‚ ã“ã‚Œã«å¯¾ã—ã€ã‚‚ã—ï¼˜ã¤ã®æ–‡å—ã«ã°ã‚‰ã¤ããŒã‚ã‚‹ã€ã¤ã¾ã‚Šå‡ºç¾ç¢ºçŽ‡ãŒé•ã†å ´åˆã«ã¯ å¤šãå‡ºã¦ãã‚‹æ–‡å—ã«å¯¾
mogwaing 2009/05/20
exclusionã®èª¬æ˜ŽãŒã‚ã‹ã‚Šã‚„ã™ã™ãŽã‚‹

algorithm

compression

ppm
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1