{"id":1151,"date":"2023-04-16T11:52:30","date_gmt":"2023-04-16T08:52:30","guid":{"rendered":"https:\/\/legendhomework.com\/tr\/?p=1151"},"modified":"2023-04-16T11:52:30","modified_gmt":"2023-04-16T08:52:30","slug":"filigrani-gizleme-multimedya-bolumu-multimedya-bolumu-odevleri-multimedya-bolumu-tez-yaptirma-multimedya-bolumu-odev-ucretleri","status":"publish","type":"post","link":"https:\/\/legendhomework.com\/tr\/filigrani-gizleme-multimedya-bolumu-multimedya-bolumu-odevleri-multimedya-bolumu-tez-yaptirma-multimedya-bolumu-odev-ucretleri\/","title":{"rendered":"Filigran\u0131 Gizleme\u00a0 \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":"

Gri \u00d6l\u00e7ekli Bir Filigran\u0131 Gizleme<\/span><\/strong><\/h3>\n

Deneylerde 256 \u00d7 256 boyutundaki pop\u00fcler Lena g\u00f6r\u00fcnt\u00fcs\u00fc kullan\u0131ld\u0131 ve filigranl\u0131 g\u00f6r\u00fcnt\u00fc, g\u00f6rsel artefakt i\u00e7ermeyen 35 dB tepe sinyal-g\u00fcr\u00fclt\u00fc oran\u0131na (PSNR) sahipti.<\/span><\/p>\n

Bulan\u0131kla\u015ft\u0131rma sald\u0131r\u0131s\u0131: Filigranl\u0131 g\u00f6r\u00fcnt\u00fc, Gauss varyans\u0131 7 (pencere boyutu 15 \u00d7 15) olan d\u00fc\u015f\u00fck ge\u00e7i\u015fli bir filtre kullan\u0131larak g\u00fc\u00e7l\u00fc bir \u015fekilde bulan\u0131kla\u015ft\u0131r\u0131ld\u0131. Temel olarak, filigranl\u0131 g\u00f6r\u00fcnt\u00fcn\u00fcn y\u00fcksek frekansl\u0131 bile\u015fenleri bu i\u015flemden sonra \u00e7\u0131kar\u0131lm\u0131\u015ft\u0131r. Al\u0131nan filigran\u0131n olduk\u00e7a tan\u0131nabilir oldu\u011fu sonu\u00e7 g\u00f6sterilir.<\/span><\/p>\n

Medyan filtreleme sald\u0131r\u0131s\u0131: Benzer \u015fekilde, filigranl\u0131 g\u00f6r\u00fcnt\u00fc, 7 \u00d7 7’lik bir maske kullan\u0131larak medyan filtrelendi. Medyan filtreleme sald\u0131r\u0131s\u0131ndan sonraki sonu\u00e7lar g\u00f6sterilmektedir, burada geri al\u0131nan filigran yine \u00e7ok belirgindir.<\/span><\/p>\n

G\u00f6r\u00fcnt\u00fc yeniden \u00f6l\u00e7eklendirme: Filigran eklenmi\u015f g\u00f6r\u00fcnt\u00fc, orijinal boyutunun d\u00f6rtte birine \u00f6l\u00e7eklendi ve orijinal boyutlar\u0131na g\u00f6re \u00fcst \u00f6rneklendi. Bir\u00e7ok detay\u0131n kayboldu\u011funu g\u00f6rebiliriz. Al\u0131nan filigran\u0131 g\u00f6sterir.<\/span><\/p>\n

JPEG s\u0131k\u0131\u015ft\u0131rma sald\u0131r\u0131s\u0131: JPEG s\u0131k\u0131\u015ft\u0131rma algoritmas\u0131, filigran\u0131n en dayan\u0131kl\u0131 olmas\u0131 gereken sald\u0131r\u0131lardan biridir. JPEG s\u0131k\u0131\u015ft\u0131rmas\u0131n\u0131n etkisi, %5 gibi \u00e7ok d\u00fc\u015f\u00fck bir kalite fakt\u00f6r\u00fc kullan\u0131larak incelenmi\u015ftir.<\/span><\/p>\n

JPEG s\u0131k\u0131\u015ft\u0131rmas\u0131ndan sonra filigranl\u0131 g\u00f6r\u00fcnt\u00fcy\u00fc g\u00f6sterir. G\u00f6rsel olarak, filigranl\u0131 g\u00f6r\u00fcnt\u00fc, bariz bloklu efektler i\u00e7erdi\u011finden ciddi \u015fekilde zarar g\u00f6rm\u00fc\u015ft\u00fcr. G\u00f6sterilen filigran, \u00e7\u0131kar\u0131lan sonu\u00e7tur. Al\u0131nan filigran\u0131n \u00e7ok net oldu\u011fu a\u00e7\u0131kt\u0131r.<\/span><\/p>\n

EZW s\u0131k\u0131\u015ft\u0131rma sald\u0131r\u0131s\u0131 : G\u00f6m\u00fcl\u00fc s\u0131f\u0131r a\u011fa\u00e7 (EZW) s\u0131k\u0131\u015ft\u0131rma algoritmas\u0131, filigran\u0131n en dayan\u0131kl\u0131 olmas\u0131 gereken sald\u0131r\u0131lardan bir di\u011feridir. Filigranl\u0131 g\u00f6r\u00fcnt\u00fc, SPIHT s\u0131k\u0131\u015ft\u0131rmas\u0131 (EZW s\u0131k\u0131\u015ft\u0131rma ailesinin bir \u00fcyesi) taraf\u0131ndan sald\u0131r\u0131ya u\u011frad\u0131.<\/span><\/p>\n

S\u0131k\u0131\u015ft\u0131r\u0131lm\u0131\u015f sonu\u00e7 g\u00f6sterilir. Bozulman\u0131n olduk\u00e7a \u00f6nemli oldu\u011fu a\u00e7\u0131kt\u0131r. Bununla birlikte, g\u00f6sterilen yeniden yap\u0131land\u0131r\u0131lm\u0131\u015f filigran yeniden tan\u0131nabilir.<\/span><\/p>\n

Titre\u015fim sald\u0131r\u0131s\u0131: Titre\u015fim sald\u0131r\u0131s\u0131, filigranl\u0131 bir g\u00f6r\u00fcnt\u00fcye geometrik bozulmalar getiren bir t\u00fcr sald\u0131r\u0131d\u0131r. Titre\u015fim sald\u0131r\u0131s\u0131ndan sonraki sonucu, silinen ve \u00e7o\u011falt\u0131lan d\u00f6rt \u00e7ift s\u00fctunla g\u00f6sterir. Bu sald\u0131r\u0131n\u0131n verdi\u011fi hasar\u0131n g\u00f6zle g\u00f6r\u00fclmedi\u011fi a\u00e7\u0131kt\u0131r. Al\u0131nan filigran\u0131 herhangi bir senkronizasyon i\u015flemi ger\u00e7ekle\u015ftirmeden g\u00f6sterir. Yine, al\u0131nan sonu\u00e7 hala tan\u0131nabilir.<\/span><\/p>\n

StirMark sald\u0131r\u0131s\u0131: StirMark taraf\u0131ndan sald\u0131r\u0131ya u\u011frayan filigranl\u0131 g\u00f6r\u00fcnt\u00fc g\u00f6sterilir. StirMark yaz\u0131l\u0131m\u0131n\u0131n t\u00fcm varsay\u0131lan parametreleri kullan\u0131ld\u0131. Sald\u0131r\u0131 \u00f6ncesi ve sonras\u0131 filigranl\u0131 g\u00f6r\u00fcnt\u00fcn\u00fcn hemen hemen ayn\u0131 oldu\u011fu ancak asl\u0131nda geometrik olarak bozuldu\u011fu alg\u0131lanmaktad\u0131r.<\/span><\/p>\n

Bu bozulmalar kafesler kullan\u0131larak g\u00f6sterilmektedir. Bozuk a\u011flardan StirMark’\u0131n g\u00fcc\u00fcn\u00fc g\u00f6rmek kolayd\u0131r. Asenkronizasyon, piyasada bulunan bir\u00e7ok filigran algoritmas\u0131n\u0131n sald\u0131r\u0131s\u0131 alt\u0131nda ba\u015far\u0131s\u0131z olmas\u0131n\u0131n nedenidir.<\/span><\/p>\n

Ay\u0131klanan filigran\u0131 g\u00f6sterir. Be\u015f kez StirMark uygulanarak sald\u0131r\u0131ya u\u011frayan filigranl\u0131 g\u00f6r\u00fcnt\u00fcy\u00fc g\u00f6sterir. G\u00f6sterilen \u00e7\u0131kar\u0131lan filigran \u015fa\u015f\u0131rt\u0131c\u0131 derecede iyidir. G\u00f6r\u00fcn\u00fc\u015fe g\u00f6re, \u00f6nerilen yer de\u011fi\u015ftirme tekni\u011fi, StirMark sald\u0131r\u0131s\u0131n\u0131n neden oldu\u011fu etkileri bozdu.<\/span><\/p>\n

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Excel filigran<\/a> kald\u0131rma<\/span>
\nFiligran kald\u0131rma<\/span>
\n\u00dccretsiz filigran kald\u0131rma<\/span>
\nKyocera Yaz\u0131c\u0131 filigran kald\u0131rma<\/span>
\nWord Filigran kald\u0131rma<\/span>
\nSayfa 1 yaz\u0131s\u0131n\u0131 kald\u0131rma<\/span>
\nFiligran kald\u0131rma Video<\/span>
\nFoto\u011fraf filigran kald\u0131rma<\/span><\/p>\n

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unZign sald\u0131r\u0131s\u0131: unZign, StirMark gibi davran\u0131r ve bunlar\u0131 kar\u015f\u0131la\u015ft\u0131ran bir rapor bulunabilir. Bir\u00e7ok ticari filigran algoritmas\u0131 da bu sald\u0131r\u0131 alt\u0131nda ba\u015far\u0131s\u0131z oldu.<\/span><\/p>\n

Bununla birlikte, elde edilen sonu\u00e7lar, hem \u00c7ince hem de \u0130ngilizce metinlerin iyi bir \u015fekilde kurtar\u0131ld\u0131\u011f\u0131n\u0131 g\u00f6stermektedir.<\/span><\/p>\n

Kombinasyon sald\u0131r\u0131lar\u0131: Yakla\u015f\u0131m\u0131m\u0131z\u0131 test etmek i\u00e7in kombinasyon sald\u0131r\u0131lar\u0131 da yap\u0131ld\u0131. StirMark sald\u0131r\u0131s\u0131, JPEG s\u0131k\u0131\u015ft\u0131rma (%5) ve bulan\u0131kla\u015ft\u0131rma (7 \u00d7 7) sonras\u0131nda filigranl\u0131 g\u00f6r\u00fcnt\u00fc g\u00f6sterilir ve al\u0131nan filigran g\u00f6sterilir.<\/span><\/p>\n

180\u00b0 d\u00f6nd\u00fcr\u00fclm\u00fc\u015f g\u00f6sterilmektedir ve ilgili al\u0131nan filigran g\u00f6sterilmektedir. \u00c7\u0131kar\u0131lan filigran\u0131n halen iyi durumda oldu\u011fu g\u00f6r\u00fclmektedir.<\/span><\/p>\n

Hile: Orijinal i\u015fareti okunamaz hale getirmeyi ama\u00e7layan birka\u00e7 filigran eklenebilir. Burada, ayn\u0131 ana bilgisayar g\u00f6r\u00fcnt\u00fcs\u00fcne ayr\u0131 ayr\u0131 be\u015f farkl\u0131 filigran g\u00f6m\u00fcld\u00fc ve ortalamas\u0131 al\u0131nd\u0131. Gizli anla\u015fma sald\u0131r\u0131s\u0131ndan sonraki filigranl\u0131 g\u00f6r\u00fcnt\u00fc g\u00f6sterilir.<\/span><\/p>\n

Bu deneyde, bir sald\u0131r\u0131n\u0131n g\u00fcc\u00fc, sald\u0131r\u0131n\u0131n parametreleri de\u011fi\u015ftirilebiliyorsa her zaman yeterince g\u00fc\u00e7l\u00fc olacak \u015fekilde ayarlanm\u0131\u015ft\u0131r. G\u00f6r\u00fcnt\u00fc bozulmas\u0131 pratik uygulamalarda kabul edilmeyecek kadar a\u011f\u0131r olsa da, iz yine de kolayl\u0131kla d\u00fczeltilebilir.<\/span><\/p>\n

\u00a0\u0130kili Filigran\u0131 Gizlemenin Sonu\u00e7lar\u0131<\/span><\/strong><\/h3>\n

Bu deneyde 256\u00d7256 ebad\u0131ndaki G\u00f6kku\u015fa\u011f\u0131 resmi kullan\u0131lm\u0131\u015ft\u0131r. \u0130kili filigran\u0131n i\u00e7eri\u011fi, 1497 \u00f6n plan pikselli \u00c7ince \u201cACADEMIA SINICA\u201d metniydi. Olu\u015fturulan filigranl\u0131 g\u00f6r\u00fcnt\u00fc 27.23 dB PSNR’ye sahiptir, ancak yine PSNR de\u011feri nispeten d\u00fc\u015f\u00fck oldu\u011funda bile g\u00f6rsel artefakt yoktur.<\/span><\/p>\n

\u00c7ift gizleme stratejimiz sayesinde toplam 2994 mod\u00fcle edilmi\u015f katsay\u0131 vard\u0131r. Farkl\u0131 sald\u0131r\u0131 t\u00fcrleri alt\u0131ndaki genel performans \u00f6zetlenmi\u015ftir. Bulan\u0131kla\u015ft\u0131rma ve medyan filtreleme i\u00e7in kullan\u0131lan maskelerin boyutlar\u0131 s\u0131ras\u0131yla 15\u00d715 ve 11\u00d711 idi.<\/span><\/p>\n

Yeniden \u00f6l\u00e7eklendirme sald\u0131r\u0131s\u0131, gri tonlamal\u0131 filigran durumunda oldu\u011fu gibi ger\u00e7ekle\u015ftirildi. Gauss g\u00fcr\u00fclt\u00fcs\u00fcn\u00fcn varyans\u0131 16 idi ve jitter sald\u0131r\u0131s\u0131 5 s\u00fctun \u00e7iftini sildi\/g\u00fcncelledi. JPEG ve SPIHT s\u0131k\u0131\u015ft\u0131rmalar\u0131n\u0131n alt\u0131ndaki %5 ve 128:1 say\u0131lar\u0131 s\u0131ras\u0131yla kalite fakt\u00f6r\u00fcn\u00fc ve s\u0131k\u0131\u015ft\u0131rma oran\u0131n\u0131 g\u00f6sterir.<\/span><\/p>\n

StirMark sald\u0131r\u0131lar\u0131n\u0131n alt\u0131ndaki 1 ve 5 say\u0131lar\u0131, StirMark sald\u0131r\u0131s\u0131n\u0131n ger\u00e7ekle\u015ftirilme say\u0131s\u0131n\u0131 temsil eder. \u015eekil 18.16 ayr\u0131ca StirMark, flip ve jitter sald\u0131r\u0131lar\u0131n\u0131 i\u00e7eren sald\u0131r\u0131lar\u0131n bir kombinasyonunu g\u00f6stermektedir.<\/span><\/p>\n

Normalle\u015ftirilmi\u015f korelasyon de\u011feri (0 ile 1 aras\u0131nda) benzerlik \u00f6l\u00e7\u00fcm\u00fc kullan\u0131larak hesaplanm\u0131\u015ft\u0131r. Daha y\u00fcksek de\u011ferler, al\u0131nan filigran ile orijinal filigran aras\u0131nda daha iyi e\u015fle\u015fmeyi temsil eder.<\/span><\/p>\n

Tan\u0131mlanan t\u00fcm sald\u0131r\u0131lar i\u00e7in en y\u00fcksek korelasyon de\u011feri olan 1 elde edilmi\u015ftir. Bu deney dizisi, ikili gizleme \u015femas\u0131n\u0131n ger\u00e7ekten de bir ikili filigran\u0131 g\u00f6mmek i\u00e7in s\u00fcper bir mekanizma oldu\u011funu g\u00f6stermektedir.<\/span><\/p>\n

Dijital g\u00f6r\u00fcnt\u00fcleri korumak i\u00e7in bu b\u00f6l\u00fcmde sa\u011flam bir damgalama \u015femas\u0131 geli\u015ftirilmi\u015ftir. \u0130nsan g\u00f6rsel modeli taraf\u0131ndan sa\u011flanan JND e\u015fik de\u011ferleri, bir filigran\u0131n yerle\u015ftirilmesine izin verilen maksimum alg\u0131sal kapasiteye karar vermek i\u00e7in sunulmu\u015ftur.<\/span><\/p>\n

\u00d6nerilen \u015fema a\u015fa\u011f\u0131daki \u00f6zelliklere sahiptir: (1) gri \u00f6l\u00e7ekli bir filigran\u0131n ba\u011flamsal bilgisini kullan\u0131r; (2) bir ikili filigran gizleme i\u00e7in g\u00fcvenli\u011fi art\u0131rmak \u00fczere \u00e7oklu mod\u00fclasyonlar uygular; (3) bir dalgac\u0131k d\u00f6n\u00fc\u015ft\u00fcr\u00fclm\u00fc\u015f ana g\u00f6r\u00fcnt\u00fcn\u00fcn yerel skalogram\u0131na uyarlan\u0131r; (4) bir yer de\u011fi\u015ftirme tekni\u011fi kullanarak geometrik bozulmalara sahip sald\u0131r\u0131lara kar\u015f\u0131 savunma yapar; ve (5) ana bilgisayar g\u00f6r\u00fcnt\u00fcs\u00fcn\u00fc kullanmadan (dolayl\u0131 olarak) kimlik do\u011frulamas\u0131 yapar.<\/span><\/p>\n

Deneyler, damgalama \u015femam\u0131z\u0131n yaln\u0131zca \u015feffafl\u0131\u011f\u0131 de\u011fil, ayn\u0131 zamanda sa\u011flaml\u0131\u011f\u0131 da sa\u011flayabildi\u011fini ve kimlik do\u011frulaman\u0131n orijinal kaynak olmadan yap\u0131labilece\u011fini g\u00f6stermi\u015ftir.<\/span><\/p>\n

Bu b\u00f6l\u00fcmde ele al\u0131nan bir ikili filigran i\u00e7in, uzamsal alandaki \u00f6n plan pikselleri do\u011frudan bir konak g\u00f6r\u00fcnt\u00fcn\u00fcn uzay\/frekans alan\u0131na g\u00f6m\u00fcl\u00fcr. Filigran piksel say\u0131s\u0131 fazla ise veya g\u00f6m\u00fcl\u00fc ikili filigran say\u0131s\u0131 birden fazla ise, bu verileri gizlemek i\u00e7in gereken kapasite dikkate al\u0131nmal\u0131d\u0131r.<\/span><\/p>\n

\u00c7\u00f6z\u00fcmlerden biri ikili filigran\u0131 d\u00f6n\u00fc\u015ft\u00fcrmek i\u00e7in ikili dalgac\u0131k d\u00f6n\u00fc\u015f\u00fcm\u00fcn\u00fc kullanmakt\u0131r, \u00e7\u00fcnk\u00fc dalgac\u0131k alan\u0131nda \u00f6n plan piksellerinin say\u0131s\u0131 azalacakt\u0131r.<\/span><\/p>\n

Bu b\u00f6l\u00fcmde, negatif mod\u00fclasyon stratejisi benimsenmi\u015ftir. Uygulamada, baz\u0131 sald\u0131r\u0131lar hala negatif mod\u00fclasyonla yeterince a\u00e7\u0131klanamaz. Mod\u00fclasyon probleminin \u00fcstesinden geldik ve yeni bir damgalama yakla\u015f\u0131m\u0131 \u00f6nerildi, iki filigran bir konak g\u00f6r\u00fcnt\u00fcye g\u00f6m\u00fcld\u00fc ve en az bir filigran\u0131n farkl\u0131 sald\u0131r\u0131lardan sonra hayatta kalmas\u0131 i\u00e7in tamamlay\u0131c\u0131 roller oynad\u0131.<\/span><\/p>\n

Bu, \u00e7oklu ortam korumas\u0131 i\u00e7in neden pozitif mod\u00fclasyonun veya negatif mod\u00fclasyonun tek ba\u015f\u0131na yeterli olmad\u0131\u011f\u0131n\u0131 a\u00e7\u0131klar.<\/span><\/p>\n

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