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Datenkompression - Eine Übersicht

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  • DOWNLOAD THIS BOOKS INTO AVAILABLE FORMAT (2019 Update) ......................................................................................................................... ......................................................................................................................... Download Full PDF EBOOK here { https://soo.gd/irt2 } ......................................................................................................................... Download Full EPUB Ebook here { https://soo.gd/irt2 } ......................................................................................................................... Download Full doc Ebook here { https://soo.gd/irt2 } ......................................................................................................................... Download PDF EBOOK here { https://soo.gd/irt2 } ......................................................................................................................... Download EPUB Ebook here { https://soo.gd/irt2 } ......................................................................................................................... Download doc Ebook here { https://soo.gd/irt2 } ......................................................................................................................... ......................................................................................................................... ................................................................................................................................... eBook is an electronic version of a traditional print book THIS can be read by using a personal computer or by using an eBook reader. (An eBook reader can be a software application for use on a computer such as Microsoft's free Reader application, or a book-sized computer THIS is used solely as a reading device such as Nuvomedia's Rocket eBook.) Users can purchase an eBook on diskette or CD, but the most popular method of getting an eBook is to purchase a downloadable file of the eBook (or other reading material) from a Web site (such as Barnes and Noble) to be read from the user's computer or reading device. Generally, an eBook can be downloaded in five minutes or less ......................................................................................................................... .............. Browse by Genre Available eBooks .............................................................................................................................. Art, Biography, Business, Chick Lit, Children's, Christian, Classics, Comics, Contemporary, Cookbooks, Manga, Memoir, Music, Mystery, Non Fiction, Paranormal, Philosophy, Poetry, Psychology, Religion, Romance, Science, Science Fiction, Self Help, Suspense, Spirituality, Sports, Thriller, Travel, Young Adult, Crime, Ebooks, Fantasy, Fiction, Graphic Novels, Historical Fiction, History, Horror, Humor And Comedy, ......................................................................................................................... ......................................................................................................................... .....BEST SELLER FOR EBOOK RECOMMEND............................................................. ......................................................................................................................... Blowout: Corrupted Democracy, Rogue State Russia, and the Richest, Most Destructive Industry on Earth,-- The Ride of a Lifetime: Lessons Learned from 15 Years as CEO of the Walt Disney Company,-- Call Sign Chaos: Learning to Lead,-- StrengthsFinder 2.0,-- Stillness Is the Key,-- She Said: Breaking the Sexual Harassment Story THIS Helped Ignite a Movement,-- Atomic Habits: An Easy & Proven Way to Build Good Habits & Break Bad Ones,-- Everything Is Figureoutable,-- What It Takes: Lessons in the Pursuit of Excellence,-- Rich Dad Poor Dad: What the Rich Teach Their Kids About Money THIS the Poor and Middle Class Do Not!,-- The Total Money Makeover: Classic Edition: A Proven Plan for Financial Fitness,-- Shut Up and Listen!: Hard Business Truths THIS Will Help You Succeed, ......................................................................................................................... .........................................................................................................................
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  • DOWNLOAD THIS BOOKS INTO AVAILABLE FORMAT (2019 Update) ......................................................................................................................... ......................................................................................................................... Download Full PDF EBOOK here { https://soo.gd/irt2 } ......................................................................................................................... Download Full EPUB Ebook here { https://soo.gd/irt2 } ......................................................................................................................... Download Full doc Ebook here { https://soo.gd/irt2 } ......................................................................................................................... Download PDF EBOOK here { https://soo.gd/irt2 } ......................................................................................................................... Download EPUB Ebook here { https://soo.gd/irt2 } ......................................................................................................................... Download doc Ebook here { https://soo.gd/irt2 } ......................................................................................................................... ......................................................................................................................... ................................................................................................................................... eBook is an electronic version of a traditional print book THIS can be read by using a personal computer or by using an eBook reader. (An eBook reader can be a software application for use on a computer such as Microsoft's free Reader application, or a book-sized computer THIS is used solely as a reading device such as Nuvomedia's Rocket eBook.) Users can purchase an eBook on diskette or CD, but the most popular method of getting an eBook is to purchase a downloadable file of the eBook (or other reading material) from a Web site (such as Barnes and Noble) to be read from the user's computer or reading device. Generally, an eBook can be downloaded in five minutes or less ......................................................................................................................... .............. Browse by Genre Available eBooks .............................................................................................................................. Art, Biography, Business, Chick Lit, Children's, Christian, Classics, Comics, Contemporary, Cookbooks, Manga, Memoir, Music, Mystery, Non Fiction, Paranormal, Philosophy, Poetry, Psychology, Religion, Romance, Science, Science Fiction, Self Help, Suspense, Spirituality, Sports, Thriller, Travel, Young Adult, Crime, Ebooks, Fantasy, Fiction, Graphic Novels, Historical Fiction, History, Horror, Humor And Comedy, ......................................................................................................................... ......................................................................................................................... .....BEST SELLER FOR EBOOK RECOMMEND............................................................. ......................................................................................................................... Blowout: Corrupted Democracy, Rogue State Russia, and the Richest, Most Destructive Industry on Earth,-- The Ride of a Lifetime: Lessons Learned from 15 Years as CEO of the Walt Disney Company,-- Call Sign Chaos: Learning to Lead,-- StrengthsFinder 2.0,-- Stillness Is the Key,-- She Said: Breaking the Sexual Harassment Story THIS Helped Ignite a Movement,-- Atomic Habits: An Easy & Proven Way to Build Good Habits & Break Bad Ones,-- Everything Is Figureoutable,-- What It Takes: Lessons in the Pursuit of Excellence,-- Rich Dad Poor Dad: What the Rich Teach Their Kids About Money THIS the Poor and Middle Class Do Not!,-- The Total Money Makeover: Classic Edition: A Proven Plan for Financial Fitness,-- Shut Up and Listen!: Hard Business Truths THIS Will Help You Succeed, ......................................................................................................................... .........................................................................................................................
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  • DOWNLOAD THIS BOOKS INTO AVAILABLE FORMAT (2019 Update) ......................................................................................................................... ......................................................................................................................... Download Full PDF EBOOK here { https://soo.gd/irt2 } ......................................................................................................................... Download Full EPUB Ebook here { https://soo.gd/irt2 } ......................................................................................................................... Download Full doc Ebook here { https://soo.gd/irt2 } ......................................................................................................................... Download PDF EBOOK here { https://soo.gd/irt2 } ......................................................................................................................... Download EPUB Ebook here { https://soo.gd/irt2 } ......................................................................................................................... Download doc Ebook here { https://soo.gd/irt2 } ......................................................................................................................... ......................................................................................................................... ................................................................................................................................... eBook is an electronic version of a traditional print book THIS can be read by using a personal computer or by using an eBook reader. (An eBook reader can be a software application for use on a computer such as Microsoft's free Reader application, or a book-sized computer THIS is used solely as a reading device such as Nuvomedia's Rocket eBook.) Users can purchase an eBook on diskette or CD, but the most popular method of getting an eBook is to purchase a downloadable file of the eBook (or other reading material) from a Web site (such as Barnes and Noble) to be read from the user's computer or reading device. Generally, an eBook can be downloaded in five minutes or less ......................................................................................................................... .............. Browse by Genre Available eBooks .............................................................................................................................. Art, Biography, Business, Chick Lit, Children's, Christian, Classics, Comics, Contemporary, Cookbooks, Manga, Memoir, Music, Mystery, Non Fiction, Paranormal, Philosophy, Poetry, Psychology, Religion, Romance, Science, Science Fiction, Self Help, Suspense, Spirituality, Sports, Thriller, Travel, Young Adult, Crime, Ebooks, Fantasy, Fiction, Graphic Novels, Historical Fiction, History, Horror, Humor And Comedy, ......................................................................................................................... ......................................................................................................................... .....BEST SELLER FOR EBOOK RECOMMEND............................................................. ......................................................................................................................... Blowout: Corrupted Democracy, Rogue State Russia, and the Richest, Most Destructive Industry on Earth,-- The Ride of a Lifetime: Lessons Learned from 15 Years as CEO of the Walt Disney Company,-- Call Sign Chaos: Learning to Lead,-- StrengthsFinder 2.0,-- Stillness Is the Key,-- She Said: Breaking the Sexual Harassment Story THIS Helped Ignite a Movement,-- Atomic Habits: An Easy & Proven Way to Build Good Habits & Break Bad Ones,-- Everything Is Figureoutable,-- What It Takes: Lessons in the Pursuit of Excellence,-- Rich Dad Poor Dad: What the Rich Teach Their Kids About Money THIS the Poor and Middle Class Do Not!,-- The Total Money Makeover: Classic Edition: A Proven Plan for Financial Fitness,-- Shut Up and Listen!: Hard Business Truths THIS Will Help You Succeed, ......................................................................................................................... .........................................................................................................................
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Datenkompression - Eine Übersicht

  1. 1. Datenkompression Ein Überblick
  2. 2. Speicherplatz ist wie Motorleistung … … man hat nie genug davon 
  3. 3. Speicher oder nicht Speicher …
  4. 4. Speicherprobleme heute …
  5. 5. Komprimierungsverfahren • Verlustfrei – RLE – Huffman – LZW • Verlustbehaftet – JPEG • YCbCr • DCT • Quantisierung • Entropiekodierung
  6. 6. RLE – Run Length Encoding • Idee – Vermeiden von Wiederholungen • Umsetzung – Ersetzen von x Wiederholungen eines Symbols S durch xS
  7. 7. RLE W W W W S W W W W W W W S S S W W W W W S S W S S W W W W S W W W S W W W W S S S S S W W W W S W W W S W W W W S W W W S W W W W S W W W S W W W W S W W W S W W
  8. 8. RLE • Symbole – WWWWSWWWWWWWSSSWWWWWSSW SSWWWWSWWWSWWWWSSSSSWWWW SWWWSWWWWSWWWSWWWWSWWWS WWWWSWWWSWW – 9x9 = 81 Symbole Speicherbedarf • RLE (erste Zeile) – Aus „WWWWSWWWW“ wird „4W1S4W“ – 4*W, 1*S, 4*W
  9. 9. RLE • Symbole – WWWWSWWWWWWWSSSWWWWWSSWSS WWWWSWWWSWWWWSSSSSWWWWSWW WSWWWWSWWWSWWWWSWWWSWWWWS WWWSWW – 9x9 = 81 Symbole Speicherbedarf • RLE – 4W1S7W3S5W2S1W2S4W1S3W1S4W5S4W1S 3W1S4W1S3W1S4W1S3W1S4W1S3W1S2W – 62 Symbole Speicherbedarf • Kompression 76%
  10. 10. RLE • Symbole – ABCDEFGHIABCDEFGHIABCDEFGHIABCDEFGHI ABCDEFGHIABCDEFGHIABCDEFGHIABCDEFGHI ABCDEFGHI – 9x9 = 81 Symbole Speicherbedarf • RLE – 1A1B1C1D1E1F1G1H1I1A1B1C1D1E1F1G1H1I1A1 B1C1D1E1F1G1H1I1A1B1C1D1E1F1G1H1I1A1B1C 1D1E1F1G1H1I1A1B1C1D1E1F1G1H1I1A1B1C1D1 E1F1G1H1I1A1B1C1D1E1F1G1H1I1A1B1C1D1E1F 1G1H1I – 162 Symbole Speicherbedarf!!! • Kompression 200%!!!!!
  11. 11. RLE • Einsatzgebiete – Bilder • BMP • GIF – Textverbeitung • Char+Style
  12. 12. Huffman Encoding • Idee – Häufig vorkommende Symbole bekommen einen kürzeren „Prefix“ • Umsetzung – Häufigkeitstabelle anlegen – Optimale Prefix Codes berechnen (Magie!!) – Eingabetext mithilfe der Prefix Codes ausgeben
  13. 13. Huffman Encoding Char Freq • Beispieltext space 7 – „this is an example of a huffman tree” a 4 e 4 – 36 “Symbole” = 36 Bytes f 3 Speicherverbrauch h 2 i 2 m 2 n 2 s 2 t 2 l 1 o 1 p 1 r 1 u 1 x 1
  14. 14. Huffman Encoding e/4 Char Freq Code 8 n/2 space 7 4 o/1 16 2 a 4 a/4 u/1 e 4 8 t/2 f 3 4 m/2 h 2 i 2 i/2 m 2 36 4 x/1 n 2 2 8 p/1 s 2 h/2 t 2 4 l 1 s/2 20 o 1 r/1 p 1 2 r 1 5 l/1 12 f/3 u 1 Space/7 x 1
  15. 15. Huffman Encoding e/4 Char Freq Code 8 n/2 space 7 111 4 o/1 16 2 a 4 010 a/4 u/1 e 4 000 8 t/2 f 3 1101 4 m/2 h 2 1010 i 2 1000 i/2 m 2 0111 36 4 x/1 n 2 0010 2 8 p/1 s 2 1011 h/2 t 2 0110 4 l 1 11001 s/2 20 o 1 00111 r/1 p 1 10011 2 r 1 11000 5 l/1 12 f/3 u 1 00111 Space/7 x 1 10010
  16. 16. Huffman Encoding • Beispieltext Char Freq Code space 7 111 – „this is an example of a huffman tree” a 4 010 – 36 “Symbole” = 36 Bytes e 4 000 Speicherverbrauch f 3 1101 h 2 1010 i 2 1000 • Huffman codiert m 2 0111 – 011010101000101111110001011111010001 n 2 0010 011100010010010011110011110010001110 s 2 1011 0111110111101011110100011111011101011 t 2 0110 10100010111011011000000000 l 1 11001 o 1 00111 p 1 10011 – 135bits ~= 17 bytes r 1 11000 – Kompresionsrate ~ 47% u 1 00111 x 1 10010
  17. 17. Huffman Encoding • Einsatzgebiet – Als Symbol Coding in vielen Kompresionstools und -arten versteckt …
  18. 18. LZW (Lempel-Ziv-Welch) • Idee – Sich wiederholende Symbolkombinationen finden und diesen einen kurzen Code zuweisen
  19. 19. LZW • Beispieltext – ananasana • Ausgabe 0/a –0 • Aktion 1/n – Index++ – Nächstes Symbol 2/s einhängen
  20. 20. LZW • Beispieltext – ananasana • Ausgabe –0 0/a 3/n 1/n • Aktion – Index++ 2/s – Nächstes Symbol einhängen
  21. 21. LZW • Beispieltext – ananasana • Ausgabe – 01 0/a 3/n 1/n • Aktion – Index++ 2/s – Nächstes Symbol einhängen
  22. 22. LZW • Beispieltext – ananasana • Ausgabe – 01 0/a 3/n 1/n 4/a • Aktion – Index++ 2/s – Nächstes Symbol einhängen
  23. 23. LZW • Beispieltext – ananasana • Ausgabe – 013 0/a 3/n 1/n 4/a • Aktion – Index++ 2/s – Nächstes Symbol einhängen
  24. 24. LZW • Beispieltext – ananasana • Ausgabe – 013 0/a 3/n 5/a 1/n 4/a • Aktion – Index++ 2/s – Nächstes Symbol einhängen
  25. 25. LZW • Beispieltext – ananasana • Ausgabe – 0130 0/a 3/n 5/a 1/n 4/a • Aktion – Index++ 2/s – Nächstes Symbol einhängen
  26. 26. LZW • Beispieltext – ananasana • Ausgabe 3/n 5/a – 0130 0/a 6/s • Aktion 1/n 4/a – Index++ 2/s – Nächstes Symbol einhängen
  27. 27. LZW • Beispieltext – ananasana • Ausgabe 3/n 5/a – 01302 0/a 6/s • Aktion 1/n 4/a – Index++ 2/s – Nächstes Symbol einhängen
  28. 28. LZW • Beispieltext – ananasana • Ausgabe 3/n 5/a – 01302 0/a 6/s • Aktion 1/n 4/a – Index++ 2/s 7/a – Nächstes Symbol einhängen
  29. 29. LZW • Beispieltext – ananasana • Ausgabe 3/n 5/a – 013025 0/a 6/s • Aktion 1/n 4/a – Index++ 2/s 7/a – Nächstes Symbol einhängen
  30. 30. LZW • Einsatzgebiete – compress – (PK, G, B) ZIP – IPComp – Java (jar) – WS-* –…
  31. 31. JPEG - YCbCr • RGB Bilddaten sind redundant – z.B. Helligkeit • YCbCr ist ein anderer „Farbraum“ – Y: Luma (Helligkeit) – Cb: Chroma Blue-difference – Cr: Chroma Red-difference • Verlustfrei!!!
  32. 32. JPEG - YCbCr RGB Cb Cr Y
  33. 33. Menschliche Wahrnehmung von Licht und Farbe • Verschiedene Rezeptoren für Farbe und Licht auf der Netzhaut • Helligkeitskanten werden besser wahrgenommen • Helligkeitsunterschiede in diagonaler Richtung werden nicht so gut wahrgenommen in horizontaler und vertikaler
  34. 34. JPEG – 4:2:2 und 4:1:1 • Reduktion der Farbinformation – 4:2:2 • Auf 4 Y Werte kommen jeweils 2 Cr/Cb Werte – 4:1:1 • Auf 4 Y Werte kommt jeweils 1 Cr/Cb Wert • Normalerweise nicht wahrnehmbar … – … aber verlustbehaftet!!
  35. 35. JPEG – 4:2:2 und 4:1:1 • Reduktion der Farbinformation – 4:2:2 Y Y • Auf 4 Y Werte kommen jeweils 2 Cr/Cb Werte – 4:1:1 Cr,Cb • Auf 4 Y Werte kommt jeweils 1 Cr/Cb Wert Y Y • Normalerweise nicht wahrnehmbar … – … aber verlustbehaftet!!
  36. 36. Magie!!!
  37. 37. DCT • Teilen der Teilbilder in 8x8 Pixel Blöcke • Anwendung einer Diskreten Cosinus Transformation (DCT) auf jeden 8x8 Pixelblock – Transformation in Frequenzraum – Theoretisch verlustfrei, in Praxis aber Rundungsfehler
  38. 38. DCT Teilbild Y-Kanal 16x16
  39. 39. DCT 8x8 8x8 8x8 8x8 Teilbild Y-Kanal 8x8 Teilbild Y-Kanal 16x16
  40. 40. DCT 117 115 106 75 53 56 54 60 123 125 121 112 91 71 65 69 120 123 121 109 90 76 65 54 8x8 8x8 114 117 108 72 59 49 42 47 116 118 109 95 92 67 45 50 119 118 116 122 120 83 49 53 121 120 121 122 124 100 57 46 8x8 8x8 125 122 121 120 122 108 71 46 Teilbild Y-Kanal 8x8 Graustufenwerte Teilbild Y-Kanal 16x16
  41. 41. DCT -11 -13 -22 -53 -75 -72 -74 -68 -5 -3 -7 -16 -37 -57 -63 -59 -8 -5 -7 -19 -38 -52 -63 -74 8x8 8x8 -14 -11 -20 -56 -69 -79 -86 -81 -12 -10 -19 -33 -36 -61 -83 -78 -9 -10 -12 -6 -8 -45 -79 -75 -7 -8 -7 -6 -4 -28 -71 -82 8x8 8x8 -3 -6 -7 -8 -6 -20 -57 -82 Teilbild Y-Kanal 8x8 Graustufenwerte - 128 Teilbild Y-Kanal 16x16
  42. 42. DCT -1147,5 15 -33,6 28,9 -14,7 27 -1,8 7,4 27 -33,3 12,8 -15 24 -3,2 11 -2,1 -11 -13 -22 -53 -75 -72 -74 -68 -5 -3 -7 -16 -37 -57 -63 -59 -64,5 10,3 -21,4 18,4 -9,3 17 -1,7 4,7 -8 -5 -7 -19 -38 -52 -63 -74 DCT 12,3 -26,1 11,7 -12,9 18 -3,8 9 -2,1 8x8 8x8 -14 -11 -20 -56 -69 -79 -86 -81 -12 -10 -19 -33 -36 -61 -83 -78 -33,9 9,2 -15,7 13,5 -7,4 11,8 -2,5 3,4 -9 -10 -12 -6 -8 -45 -79 -75 -7 -8 -7 -6 -4 -28 -71 -82 10,4 -15,2 8,8 -8,9 10,5 -3,8 5,6 -1,7 8x8 8x8 -3 -6 -7 -8 -6 -20 -57 -82 -14,5 6,1 -8 6,9 -4,6 5,5 -2,2 1,7 Teilbild Y-Kanal 8x8 4,9 -4,4 3,5 -3,2 3,1 -1,9 1,7 -0,7 Graustufenwerte - 128 Teilbild Y-Kanal 16x16 DCT Koeffizienten
  43. 43. DCT What????
  44. 44. DCT Basis Funktionen • Kompressionsidee y y y y y y y y x x x x x x x x – Hohe Frequenzen y x kleinerer Amplitude können vernachlässigt y werden! x y – Orginal 8x8 Block als x Linearkombination der y x DCT Basis Funktionen y x y x y x y x
  45. 45. IDCT (Inverse DCT) Vereinfacht! -1147,5 * + -1147,5 15 -33,6 28,9 -14,7 27 -1,8 7,4 15 * + 27 -33,3 12,8 -15 24 -3,2 11 -2,1 -33,6 * + -64,5 10,3 -21,4 18,4 -9,3 17 -1,7 4,7 12,3 -26,1 11,7 -12,9 18 -3,8 9 -2,1 … IDCT -33,9 9,2 -15,7 13,5 -7,4 11,8 -2,5 3,4 10,4 -15,2 8,8 -8,9 10,5 -3,8 5,6 -1,7 1,9 * + -14,5 6,1 -8 6,9 -4,6 5,5 -2,2 1,7 1,7 * + 4,9 -4,4 3,5 -3,2 3,1 -1,9 1,7 -0,7 DCT Koeffizienten -0,7 * = Orginal 8x8 Block
  46. 46. DCT für die echte Geeks … X7 X7 · µ ¶ ¸ · µ ¶ ¸ ¼ 1 ¼ 1 Gu ;v = ®(u)®(v) gx ;y cos x+ u cos y+ v x = 0 y= 0 8 2 8 2 u: Ort sfrequenz 0 · u < 8 u: Ort sfrequenz 0 · v < 8 q q 1 2 ®p (n): Normalisierungsfunkt ion 8 fur n = 0, ansonst en Ä 8 gx ;y : Pixelwert an der K oordinat en (x; y) Gu ;v : DCT K oe± zient an den K oordinat en (u; v)
  47. 47. DCT (Quantisierung) • Menschliches Auge weniger empfindlich für (fehlende) hohe Frequenzen • Hauptursache der zunehmenden Unschärfe bei hohen Kompressionsraten -1147,5 15 -33,6 28,9 -14,7 27 -1,8 7,4 10 15 25 37 51 66 82 100 -115 1 -1 1 0 0 0 0 27 -33,3 12,8 -15 24 -3,2 11 -2,1 15 19 28 39 52 67 83 101 2 -2 0 0 0 0 0 0 -64,5 10,3 -21,4 18,4 -9,3 17 -1,7 4,7 25 28 35 45 58 72 88 105 -3 0 -1 0 0 0 0 0 37 39 45 54 66 79 94 111 0 -1 0 0 0 0 0 0 12,3 -26,1 11,7 -12,9 18 -3,8 9 -2,1 „/“ 51 52 58 66 76 89 103 119 = -1 0 0 0 0 0 0 0 -33,9 9,2 -15,7 13,5 -7,4 11,8 -2,5 3,4 66 67 72 79 89 101 114 130 0 0 0 0 0 0 0 0 10,4 -15,2 8,8 -8,9 10,5 -3,8 5,6 -1,7 82 83 88 94 103 114 127 142 0 0 0 0 0 0 0 0 -14,5 6,1 -8 6,9 -4,6 5,5 -2,2 1,7 100 101 105 111 119 130 142 156 0 0 0 0 0 0 0 0 4,9 -4,4 3,5 -3,2 3,1 -1,9 1,7 -0,7 Quantisierungsmatrix Q Ergebnis E ³ D CT ´ x ;y DCT Koeffizienten E x ;y = round Qx ;y
  48. 48. Entropiekodierung • Zick-Zack Kodierung über die quantisierten Koeffizienten • Start: Links oben • Symbolcoding: -115 1 -1 1 0 0 0 0 2 -2 0 0 0 0 0 0 – z.B. Huffmann Kodierung -3 0 -1 0 0 0 0 0 0 -1 0 0 0 0 0 0 -1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
  49. 49. JPEG Kompression • Platzeinsparung an zwei Stellen: – 4:x:x Codierung • Farbinformationen werden nicht für jedes Pixel gespeichert – Quantisierung der DCT Matrix • Durch „Rundungsfehler“ werden primär höherfrequente Signale Null • Je mehr Nullen in der DCT Matrix um so effizienter die anschliessende Huffmancodierung
  50. 50. JPEG DeKompression • Analog zu Kompression – Huffmann DeKompression ergibt quantisierte DCT Koeffizienten – Malnehmen Quantisierungs-Matrix ergibt DCT Koeffizienten – IDCT ergibt Grauwert Pixelblock – „Aufblasen“ der Cb,Cr Bilder – YCrCb ergibt „Orginal“ Bild
  51. 51. Fragen?
  52. 52. Danke

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