Due to expeditious use of multimedia entities in
the network, there is issue to protect images from piracy.
So this is required for implementation of copyright on
high priority that can preserve ownership for copyright
protection and protected images can be claimed by actual
owner only. Digital image watermarking is the
technology invented for securing images from illicit
utilize. There are many watermarking techniques in
spatial as well as in frequency domain like Discrete
Wavelet Transform and Discrete Cosine Transform.
These techniques are widely known to be more usual,
robust and imperceptible. In the paper, literature review
work give out about analysis of different attacks like
Gaussian Blur, Salt & Pepper, Gaussian Noise, Geometric
and Joint attacks on images. Also these are implemented
on DWT and DCT watermarked image using Python code
and after attack the performances are measured by Peak
Signal to Noise Ratio(PSNR) and Normalized
Correlation(NC) for surveying about robustness of images
before and after attack.
Keywords : Peak Signal to Noise Ratio, Discrete Wavelet Transform, Discrete Cosine Transform