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Old 04-30-2015, 02:04 PM   #1
Sanpreet Singh
Registered: Jan 2013
Location: Malout,Punjab
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To rotate an image with minimum changes in Its pixels

I am doing a project on Image Watermarking using Discrete Wavelet Transform. I have done with watermarked image,Now I am attacking image with attack like rotation. My question is that when I apply function imrotate to the watermarked image, all the pixels that are not included in the rotated image becomes zero as it is property of imrotate. Due to this I got very low PSNR between Original Image and rotated Watermarked image.

My question is-I want to rotate the image but also need to have high value of PSNR after rotation. Is there any method that after rotation all or most pixels of rotated image resembles with pixels of original image.

Shortcoming of imrotate ie zero value of pixels outside rotated area can be removed by which method???????????????
Old 04-30-2015, 04:18 PM   #2
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If you rotate an image the only pixel that stays in the same place is the one at the center of rotation. Why would you get any correlation at all anywhere else in the image?


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