Invisible watermarking schemes in spatial and frequency domains

The paper presents two invisible approaches for hiding data in frequency and spatial domain. Both schemes were exposed to different watermarking attacks. Though the techniques used in spatial domain is not robust against many attacks but it will give useless information to the attacker unless he has the decoding key. In frequency domain, fast Fourier transform has been adopted for digital image watermarking. Central frequencies are selected to insert the data in a ring. In spatial domain, encrypted data will be inserted in the least significant bits. Also, it has been observed that the scheme in frequency domain is robust against a number of attacks. Both schemes do not require the original image for extracting the embedded data mark. Description of the frequency domain method has been discussed in detail along with the results.