{"id":1145,"date":"2023-04-08T23:33:50","date_gmt":"2023-04-08T20:33:50","guid":{"rendered":"https:\/\/legendhomework.com\/tr\/?p=1145"},"modified":"2023-04-08T23:33:50","modified_gmt":"2023-04-08T20:33:50","slug":"filigran-algoritmalari-multimedya-bolumu-multimedya-bolumu-odevleri-multimedya-bolumu-tez-yaptirma-multimedya-bolumu-odev-ucretleri","status":"publish","type":"post","link":"https:\/\/legendhomework.com\/tr\/filigran-algoritmalari-multimedya-bolumu-multimedya-bolumu-odevleri-multimedya-bolumu-tez-yaptirma-multimedya-bolumu-odev-ucretleri\/","title":{"rendered":"Filigran Algoritmalar\u0131 \u2013 Multimedya B\u00f6l\u00fcm\u00fc \u2013 Multimedya B\u00f6l\u00fcm\u00fc \u00d6devleri \u2013 Multimedya B\u00f6l\u00fcm\u00fc Tez Yapt\u0131rma \u2013Multimedya B\u00f6l\u00fcm\u00fc \u00d6dev \u00dccretleri"},"content":{"rendered":"

\u00d6nerilen Filigran Algoritmalar\u0131<\/span><\/strong><\/h3>\n

Orijinal g\u00f6r\u00fcnt\u00fcn\u00fcn (ana g\u00f6r\u00fcnt\u00fcn\u00fcn) gri tonlamal\u0131 oldu\u011fu varsay\u0131m\u0131na dayal\u0131 olarak iki damgalama algoritmas\u0131 geli\u015ftirece\u011fiz. Filigran\u0131m\u0131z, ikili bir filigran veya gri tonlamal\u0131 bir filigran olabilir ve maksimum boyutu ana g\u00f6r\u00fcnt\u00fcn\u00fcnki kadar b\u00fcy\u00fck olabilir. Bu \u00e7al\u0131\u015fmada benimsenen dalgac\u0131k d\u00f6n\u00fc\u015f\u00fcm\u00fc, en d\u00fc\u015f\u00fck band\u0131n boyutu 16 \u00d7 16 olacak \u015fekilde s\u0131n\u0131rland\u0131r\u0131lm\u0131\u015ft\u0131r. Dalgac\u0131k d\u00f6n\u00fc\u015f\u00fcm\u00fc yoluyla d\u00f6rt seviyeli bir ayr\u0131\u015ft\u0131rma \u00a0g\u00f6sterilmektedir.<\/span><\/p>\n

Filigran Yap\u0131lar\u0131<\/span><\/strong><\/p>\n

Sol orta k\u0131s\u0131mda \u201cACADEMIA SINICA\u201d ve buna kar\u015f\u0131l\u0131k gelen \u00c7ince metni resimli bir arka planda i\u00e7eren gri tonlamal\u0131 bir filigran g\u00f6sterilmektedir.<\/span><\/p>\n

\u00f6\u011fesinin sol alt k\u0131sm\u0131, \u201cACADEMIA SINICA\u201d anlam\u0131na gelen \u00c7ince metin i\u00e7eren ikili bir filigran g\u00f6sterir. \u0130kili filigranlar\u0131 g\u00f6mmek i\u00e7in ilgisiz arka plan\u0131 dikkate almay\u0131z; bunun yerine, yaln\u0131zca filigran piksellerini (\u00f6n planda) gizleriz.<\/span><\/p>\n

Yani, metni olu\u015fturan filigran pikselleri veya \u00f6n plan pikselleri g\u00f6m\u00fcl\u00fcr. Gri tonlamal\u0131 filigranlar i\u00e7in benimsedi\u011fimiz \u00f6zellik, baz\u0131 benzerlik \u00f6l\u00e7\u00fcmleri ile belirlenen objektif bir karar yerine s\u00fcbjektif yarg\u0131 i\u00e7in tan\u0131nabilir bir filigran \u00e7\u0131kar\u0131lmas\u0131d\u0131r.<\/span><\/p>\n

Gri tonlamal\u0131 bir filigran kullanman\u0131n di\u011fer bir yarar\u0131 da, tek bir filigran pikselinin varl\u0131\u011f\u0131n\u0131 kontrol etmekten kurtulabilmesidir. Farkl\u0131 sald\u0131r\u0131lar alt\u0131nda, gri tonlamal\u0131 bir filigran\u0131n hayatta kalma \u015fans\u0131 daha y\u00fcksektir. Bunun nedeni, gri tonlamal\u0131 bir filigran\u0131n sald\u0131r\u0131lardan sonra bile her zaman belirli bir d\u00fczeyde ba\u011flamsal bilgiyi koruyabilmesidir.<\/span><\/p>\n

\u015eeffafl\u0131k gereklili\u011fi kolayca ihlal edildi\u011finden, gri tonlamal\u0131 bir filigran\u0131 orijinal yo\u011funluklar\u0131yla g\u00f6mmenin son derece zor oldu\u011fu iyi bilinmektedir. Bu nedenle, g\u00f6m\u00fcl\u00fc gri tonlamal\u0131 filigran\u0131n orijinal gibi g\u00f6r\u00fcnmesini sa\u011flamak i\u00e7in insan g\u00f6rsel modelini uygulayaca\u011f\u0131z, ancak asl\u0131nda “s\u0131k\u0131\u015ft\u0131r\u0131lm\u0131\u015f”.<\/span><\/p>\n

Saklanma S\u00fcreci<\/span><\/strong><\/h3>\n

Filigran tekni\u011fimiz bu b\u00f6l\u00fcmde detayland\u0131r\u0131lm\u0131\u015ft\u0131r. \u0130lk olarak, ana bilgisayar g\u00f6r\u00fcnt\u00fcs\u00fc ve g\u00f6rsel olarak tan\u0131nabilir bir gri tonlamal\u0131 filigran, ayr\u0131k dalgac\u0131k d\u00f6n\u00fc\u015f\u00fcm\u00fc ile d\u00f6n\u00fc\u015ft\u00fcr\u00fcl\u00fcr. \u0130kili filigran\u0131n d\u00f6n\u00fc\u015ft\u00fcr\u00fclmesi gerekmedi\u011fine dikkat edilmelidir.<\/span><\/p>\n

G\u00f6r\u00fcnt\u00fcden Ba\u011f\u0131ms\u0131z ve G\u00f6r\u00fcnt\u00fcye Ba\u011fl\u0131 Perm\u00fctasyonlar<\/span><\/strong><\/h3>\n

D\u00f6n\u00fc\u015ft\u00fcr\u00fclen gri tonlu filigran\u0131 ve d\u00f6n\u00fc\u015ft\u00fcr\u00fclmemi\u015f ikili filigran\u0131 istatistiksel olarak tespit edilemez k\u0131lmak i\u00e7in \u201ctoral otomorfizm\u201d ad\u0131 verilen kaotik bir sistem kullan\u0131larak mekansal olarak d\u00f6n\u00fc\u015ft\u00fcr\u00fcl\u00fcrler.<\/span><\/p>\n

Kaotik kar\u0131\u015ft\u0131rma i\u015fleminden sonra filigran, alg\u0131lanamazl\u0131\u011f\u0131 garanti edebilen g\u00fcr\u00fclt\u00fc benzeri bir forma d\u00f6n\u00fc\u015ft\u00fcr\u00fcl\u00fcr. Temel olarak toral otomorfizm, g\u00f6r\u00fcnt\u00fcden ba\u011f\u0131ms\u0131z bir t\u00fcr perm\u00fctasyondur. Ard\u0131ndan, g\u00fcvenlik seviyesini art\u0131rmak ve iki t\u00fcr filigran\u0131 gizlemek i\u00e7in yerleri se\u00e7mek \u00fczere g\u00f6r\u00fcnt\u00fcye ba\u011fl\u0131 bir perm\u00fctasyon y\u00fcr\u00fct\u00fcl\u00fcr.<\/span><\/p>\n

Yakla\u015f\u0131m\u0131m\u0131zda kullan\u0131lan g\u00f6r\u00fcnt\u00fcye ba\u011fl\u0131 perm\u00fctasyon, bir e\u015fleme i\u015flevi bi\u00e7imindedir. Ana bilgisayar g\u00f6r\u00fcnt\u00fcs\u00fc ve dalgac\u0131k alan\u0131ndaki gri \u00f6l\u00e7ekli filigran bire bir e\u015flemedir. Dalgac\u0131k katsay\u0131lar\u0131n\u0131n \u00f6nemine dayal\u0131 olarak b\u00f6yle bir e\u015fleme i\u015flevi tasarl\u0131yoruz.<\/span><\/p>\n

Filigranlar daha b\u00fcy\u00fck katsay\u0131lara sahip bile\u015fenlere g\u00f6m\u00fcld\u00fc\u011f\u00fc i\u00e7in g\u00fcvenlik d\u00fczeyi y\u00fckseltilir. Bu anlaml\u0131 katsay\u0131lar, \u00f6zellikle s\u0131k\u0131\u015ft\u0131rma yap\u0131ld\u0131\u011f\u0131nda anlams\u0131z katsay\u0131lardan daha g\u00fcvenlidir. Bunun nedeni, s\u0131k\u0131\u015ft\u0131rma sald\u0131r\u0131s\u0131 alt\u0131nda, \u00f6nemli katsay\u0131lar\u0131n hayatta kalma olas\u0131l\u0131\u011f\u0131n\u0131n daha y\u00fcksek olmas\u0131d\u0131r.<\/span><\/p>\n

Yani, mod\u00fclasyon miktar\u0131, dalgac\u0131k d\u00f6n\u00fc\u015f\u00fcm\u00fcn\u00fcn skalogram\u0131 ile orant\u0131l\u0131d\u0131r. \u00d6nem kavram\u0131, Shapiro’nun EZW s\u0131k\u0131\u015ft\u0131rma \u015femas\u0131ndan esinlenmi\u015ftir. Bir dalgac\u0131k katsay\u0131s\u0131n\u0131n b\u00fcy\u00fckl\u00fc\u011f\u00fc ne kadar b\u00fcy\u00fckse, o kadar \u00f6nemlidir. Ana g\u00f6r\u00fcnt\u00fcn\u00fcn ve gri \u00f6l\u00e7ekli filigran\u0131n dalgac\u0131k katsay\u0131lar\u0131 s\u0131raland\u0131ktan sonra, e\u015fleme i\u015flevi tan\u0131mlan\u0131r.<\/span><\/p>\n

Bir ikili filigran i\u00e7in daha iyi g\u00fcvenlik elde etmek amac\u0131yla, ikili filigran\u0131n aktif piksellerini ana g\u00f6r\u00fcnt\u00fcn\u00fcn dalgac\u0131k alan\u0131na iki kez yerle\u015ftirmeyi \u00f6neriyoruz. \u00c7ift ekleme, \u00f6zellikle filigranl\u0131 g\u00f6r\u00fcnt\u00fclere sald\u0131r\u0131ld\u0131\u011f\u0131nda, bir filigran pikselinin varl\u0131\u011f\u0131n\u0131 \u00e7apraz destekleme \u00f6zelli\u011fine sahiptir. Bu nedenle, ikili filigranlar\u0131 gizlemek i\u00e7in e\u015fleme i\u015flevi ikiye bir i\u015flev olarak d\u00fc\u015f\u00fcn\u00fclebilir.<\/span><\/p>\n

(xp , yp ) ve (xn , yn ) ana g\u00f6r\u00fcnt\u00fcn\u00fcn pozitif ve negatif dalgac\u0131k katsay\u0131lar\u0131n\u0131n s\u0131ras\u0131yla konumlar\u0131d\u0131r; (xm, ym), bir ikili filigrandaki \u00f6n plan pikselinin konumudur. E\u015fleme i\u015flevleri olmadan, g\u00f6m\u00fcl\u00fc filigran\u0131n konumunu tahmin etmek zordur.<\/span><\/p>\n

Filigranlar\u0131n \u00f6nemli frekans bile\u015fenlerine g\u00f6m\u00fclmesi, dalgac\u0131k d\u00f6n\u00fc\u015ft\u00fcr\u00fclm\u00fc\u015f ana bilgisayar g\u00f6r\u00fcnt\u00fclerinin yerel skalogram\u0131na otomatik uyarlama anlam\u0131na gelir.<\/span><\/p>\n

\n

Kamerada filigran<\/a> nedir<\/span>
\nTelefonda filigran Nedir<\/span>
\nFiligran ekleme<\/span>
\nWord filigran d\u00fczenleme<\/span>
\nFoto\u011frafa filigran ekleme<\/span>
\nWord filigran ekleme<\/span>
\nTiktok filigran Nedir<\/span>
\nWord filigran Nedir<\/span><\/p>\n

\n

S\u0131k\u0131\u015ft\u0131rma Uyarlamal\u0131 Gizleme<\/span><\/strong><\/h3>\n

Gizli e\u015fleme s\u00fcrecini tamamlad\u0131ktan sonra, ana g\u00f6r\u00fcnt\u00fcn\u00fcn dalgac\u0131k katsay\u0131lar\u0131n\u0131 nas\u0131l de\u011fi\u015ftirece\u011fimizi ve de\u011fi\u015fikli\u011fin kapsam\u0131n\u0131 ele alaca\u011f\u0131z. Damgalamada en \u00f6nemli sorun, damgalanan g\u00f6r\u00fcnt\u00fcn\u00fcn herhangi bir g\u00f6rsel artefakt i\u00e7ermemesidir.<\/span><\/p>\n

Daha \u00f6nce, bir ana bilgisayar g\u00f6r\u00fcnt\u00fcs\u00fcn\u00fcn yo\u011funluklar\u0131n\u0131 k\u00fc\u00e7\u00fck bir aral\u0131kta de\u011fi\u015ftirdi ve g\u00fcncellemenin alg\u0131sal olarak fark edilmeyece\u011fini umuyordu. Ancak alg\u0131sal g\u00f6r\u00fcnmezlik elde etmek i\u00e7in modifikasyon aral\u0131\u011f\u0131n\u0131n ne olmas\u0131 gerekti\u011fini net bir \u015fekilde ele almam\u0131\u015flard\u0131r. Burada HVS’yi dikkate alaca\u011f\u0131z.<\/span><\/p>\n

G\u00f6r\u00fcnt\u00fclerin (veya di\u011fer ortamlar\u0131n) a\u011flar arac\u0131l\u0131\u011f\u0131yla iletilmesi gerekti\u011finden, trafik s\u0131k\u0131\u015f\u0131kl\u0131\u011f\u0131 sorununun \u00f6nlenebilmesi i\u00e7in s\u0131k\u0131\u015ft\u0131rma prosed\u00fcr\u00fcn\u00fcn kullan\u0131lmas\u0131 gerekir. Bu nedenle, herhangi bir filigran tekni\u011fi, s\u0131k\u0131\u015ft\u0131rma tarz\u0131 \u201csald\u0131r\u0131y\u0131\u201d dikkate almal\u0131d\u0131r. Bu b\u00f6l\u00fcmde, dalgac\u0131k d\u00f6n\u00fc\u015ft\u00fcr\u00fclm\u00fc\u015f alandaki katsay\u0131lar\u0131 mod\u00fcle ederek filigran\u0131 g\u00f6mece\u011fiz; bu nedenle, dalgac\u0131k katsay\u0131lar\u0131n\u0131n mod\u00fclasyon miktar\u0131, genel bir s\u0131k\u0131\u015ft\u0131rma i\u015flemine uyum sa\u011flayabilmelidir.<\/span><\/p>\n

Genellikle, bir g\u00f6r\u00fcnt\u00fc belirli bir oranda s\u0131k\u0131\u015ft\u0131r\u0131ld\u0131\u011f\u0131nda, d\u00f6n\u00fc\u015ft\u00fcr\u00fclen anlams\u0131z katsay\u0131lar\u0131n\u0131n mutlak de\u011ferleri k\u00fc\u00e7\u00fck de\u011ferlere veya s\u0131f\u0131ra indirgenir.<\/span><\/p>\n

\u00d6te yandan, anlaml\u0131 katsay\u0131lar\u0131n mutlak de\u011ferleri de bir miktar azalt\u0131lmaktad\u0131r. Mod\u00fcle edilen miktar\u0131n i\u015fareti g\u00fcncellenecek bir dalgac\u0131k katsay\u0131s\u0131n\u0131n i\u015faretiyle ayn\u0131ysa, ilgili filigranl\u0131 g\u00f6r\u00fcnt\u00fcn\u00fcn s\u0131k\u0131\u015ft\u0131rmadan sonra g\u00f6r\u00fcnt\u00fc kalitesini daha iyi koruyaca\u011f\u0131n\u0131 g\u00f6zlemledik.<\/span><\/p>\n

Ancak, s\u0131k\u0131\u015ft\u0131r\u0131lm\u0131\u015f filigranl\u0131 g\u00f6r\u00fcnt\u00fcn\u00fcn sa\u011flaml\u0131\u011f\u0131 ayn\u0131 ko\u015fullar alt\u0131nda bozulacakt\u0131r. Bunun nedeni, dedekt\u00f6r yan\u0131t\u0131yla yak\u0131ndan ilgili olan sa\u011flaml\u0131k sorununun ihlal edilmi\u015f olmas\u0131d\u0131r. Dolay\u0131s\u0131yla, g\u00f6r\u00fcnt\u00fc kalitesi ile sa\u011flaml\u0131k aras\u0131nda bir de\u011fi\u015f toku\u015f oldu\u011funu s\u00f6yleyebiliriz.<\/span><\/p>\n

EZW tabanl\u0131 s\u0131k\u0131\u015ft\u0131rmay\u0131 80:1 oran\u0131nda kullanarak bu olguyu g\u00f6sterir. S\u0131ras\u0131yla pozitif ve negatif mod\u00fcle edilmi\u015f s\u0131k\u0131\u015ft\u0131r\u0131lm\u0131\u015f Lena g\u00f6r\u00fcnt\u00fclerini g\u00f6sterin. G\u00f6sterilen y\u00fcz k\u0131sm\u0131n\u0131n (g\u00f6zler, a\u011f\u0131z ve burun dahil) daha net oldu\u011fu a\u00e7\u0131kt\u0131r.<\/span><\/p>\n

G\u00f6r\u00fcnt\u00fc kalitesi daha iyi olmas\u0131na ra\u011fmen, \u015fapka alanlar\u0131n\u0131n \u00e7evresinde de baz\u0131 belirgin kenarlar buluyoruz. Bunun nedeni, pozitif ve negatif dalgac\u0131k katsay\u0131lar\u0131n\u0131n say\u0131s\u0131n\u0131n ayn\u0131 olmamas\u0131d\u0131r.<\/span><\/p>\n

Bir filigran\u0131 g\u00fcvenli bir \u015fekilde g\u00f6mmek i\u00e7in negatif mod\u00fclasyon stratejisi benimsenir. Yani, bir dalgac\u0131k katsay\u0131s\u0131n\u0131n i\u015fareti ve buna kar\u015f\u0131l\u0131k gelen mod\u00fclasyon miktar\u0131n\u0131n i\u015fareti farkl\u0131 olmal\u0131d\u0131r. Hem dalgac\u0131k katsay\u0131s\u0131n\u0131 hem de buna kar\u015f\u0131l\u0131k gelen mod\u00fclasyon miktar\u0131n\u0131 ayn\u0131 i\u015faret yapan pozitif mod\u00fclasyon stratejisi, g\u00f6r\u00fcnt\u00fc kalitesi i\u00e7in avantajl\u0131d\u0131r ancak sa\u011flaml\u0131\u011f\u0131 feda eder.\u00a0<\/span><\/p>\n

\n\n
<\/div>\n\n<\/div>\n \n