劉晟志 2010/03/21 homework 1. watermarking. hide “nsysu logo” into the 3 rd bit plane
TRANSCRIPT
![Page 1: 劉晟志 2010/03/21 Homework 1. watermarking. Hide “nsysu logo” into the 3 rd bit plane](https://reader036.vdocuments.net/reader036/viewer/2022062517/56649f395503460f94c565f3/html5/thumbnails/1.jpg)
劉晟志2010/03 /21
Homework 1.watermarking
![Page 2: 劉晟志 2010/03/21 Homework 1. watermarking. Hide “nsysu logo” into the 3 rd bit plane](https://reader036.vdocuments.net/reader036/viewer/2022062517/56649f395503460f94c565f3/html5/thumbnails/2.jpg)
Hide “nsysu logo” into the 3rd bit plane
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PSNR: 42.092 dB
Original Post
![Page 4: 劉晟志 2010/03/21 Homework 1. watermarking. Hide “nsysu logo” into the 3 rd bit plane](https://reader036.vdocuments.net/reader036/viewer/2022062517/56649f395503460f94c565f3/html5/thumbnails/4.jpg)
Discuss: why can’t we extract the watermarking after doing the
“Noise adding” by Photoshop?
Every pixel had been change during the process The noise rate only decides the weight of the noise that
will be add to every pixel As the result, the watermarking can not avoid attack
Add black spot noise
![Page 5: 劉晟志 2010/03/21 Homework 1. watermarking. Hide “nsysu logo” into the 3 rd bit plane](https://reader036.vdocuments.net/reader036/viewer/2022062517/56649f395503460f94c565f3/html5/thumbnails/5.jpg)
Add black spot noise with different occur rate (gray level watermarking)
5% 10% 15% 20%
![Page 6: 劉晟志 2010/03/21 Homework 1. watermarking. Hide “nsysu logo” into the 3 rd bit plane](https://reader036.vdocuments.net/reader036/viewer/2022062517/56649f395503460f94c565f3/html5/thumbnails/6.jpg)
Add black spot noise with different occur rate (binary watermarking)
5% 10% 15% 20%
![Page 7: 劉晟志 2010/03/21 Homework 1. watermarking. Hide “nsysu logo” into the 3 rd bit plane](https://reader036.vdocuments.net/reader036/viewer/2022062517/56649f395503460f94c565f3/html5/thumbnails/7.jpg)
Different JPEG compress rate
5% 10% 15% 20%
Cover image
Water marking
![Page 8: 劉晟志 2010/03/21 Homework 1. watermarking. Hide “nsysu logo” into the 3 rd bit plane](https://reader036.vdocuments.net/reader036/viewer/2022062517/56649f395503460f94c565f3/html5/thumbnails/8.jpg)
Discuss: why can’t we extract the watermarking after doing the
“Noise adding” by Photoshop?
Every pixel had been change during the process The noise rate only decides the weight of the noise that
will be add to every pixel As the result, the watermarking can not avoid this kind of
noise attack
![Page 9: 劉晟志 2010/03/21 Homework 1. watermarking. Hide “nsysu logo” into the 3 rd bit plane](https://reader036.vdocuments.net/reader036/viewer/2022062517/56649f395503460f94c565f3/html5/thumbnails/9.jpg)
End