Performance evaluation of DWT based image watermarking using error correcting codes

Due to excessive proliferation of digital multimedia, the need of protecting the ownership of digital media becomes a major issue. For content protection digital image watermarking plays an important role in Multimedia security fields. Methods developed under this are used to protect Intellectual property rights of digital data such as video, image, audio, etc. without affecting the fidelity of the original data. In this paper we show that if the logo is coded using error correcting codes before being embedded into the watermarked image the robustness of the watermark is increased. Different codes that are taken into consideration in this paper are Hamming and cyclic codes. Here the encoded and embedded watermarked image is considered to be encountering an AWG noise while transmission. We observe that the SNR and PSNR of the watermarked image even in AWGN channel are better when logo is coded before embedding. Also we observe that Hamming codes SNR and PSNR are much more superior to cyclic codes.