Re: [問題] 傅立葉濾鏡與隱形水印
閒閒沒事做來玩玩看lol
WaterMark[pic_?(3 == ArrayDepth@# &), mark_?(3 == ArrayDepth@# &)] /;
And @@ Thread[Dimensions[pic] >= Dimensions[mark]] :=
With[{lx = Length@mark, ly = Length@mark[[1]],
F = FourierDCT[#, 1] & /@ # &, ch = Transpose[#, {2, 3, 1}] &,
chinv = Transpose[#, {3, 1, 2}] &},
With[{XPerm = RandomSample@Range@lx,
YPerm = RandomSample@Range@ly}, {chinv@
Map[Round@Min[Max[#, 0], 255] &,
F[F@ch@pic + (PadLeft[#, Most@Dimensions@pic] & /@
ch@Table[mark[[i, j]], {i, XPerm}, {j, YPerm}])], {-1}],
Reverse@chinv[
Table[#[[i, j]], {i,
SortBy[Transpose@{Range[-lx, -1], XPerm}, Last][[All,
1]]}, {j,
SortBy[Transpose@{Range[-ly, -1], YPerm}, Last][[All,
1]]}] & /@ F@ch@#] &}]]
用Lena測試
foreground = Import["ExampleData/lena.tif", "Data"];
background =
Rasterize[Style["清心也可以", 20, White], Background -> Black][[1, 1]]/4;
{res, per} = WaterMark[foreground, background];
Image@(per@res/(255./4))
GraphicsRow[{Image@(res/255.), Image@(foreground/255.)}]
恩看起來還不錯~不過我不知道如何用MMA測試修圖的影響就是LOL
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12/04 17:11, , 1F
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12/05 15:12, , 2F
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發現MMA有512x512版的Lena
foreground = ExampleData[{"TestImage", "Lena"}, "Data"];
background =
Rasterize[Style["清心也可以", 40, White], Background -> Black][[1, 1]]/4;
{res, per} = WaterMark[foreground, background];
Print /@ GraphicsRow /@
Map[Image, {{res, foreground},
4 per /@ {foreground[[;; 50]]~Join~res[[51 ;;]], res}}/
255., {2}];
順便測試一下修圖(把前50行換回原本的圖),看起來還蠻明顯的~
※ 編輯: AmibaGelos (140.112.4.190), 12/06/2016 11:59:49
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