Utilization of Edge Position for Digital Image Watermarking using Discriminant Analysis

A low complexity, pixel based watermarking technique has been used in this paper on the edge areas of an image to improve the quality and security of an image.

The method proposed in this paper while maintaining robustness against smoothing and compression, improves the quality of the different types of images.

To evaluate the quality of the image after applying the proposed technique the parameters such as Peak Signal to Noise Ratio (PSNR) and Structural Similarity Index (SSIM) has been computed. The watermark is embedded into selected Channels of pixel.

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Channel Estimation Technique for OFDM using an Adaptive Algorithm

Orthogonal Frequency Division Multiplexing (OFDM) is widely considered as a promising choice for future wireless communications systems due to its high-data-rate transmission capability with high bandwidth efficiency.

In OFDM, the entire channel is divided into many  narrow sub  channels, converting  a frequency-selective channel into a collection of  flat  frequency  independent  channels. Moreover, Inter Symbol Interference (ISI) is avoided by the use of Cyclic Prefix (CP). In fact, OFDM has been adopted in digital audio  broadcasting  (DAB),  digital  video broadcasting (DVB), digital subscriber line (DSL),  and  wireless  local  area  network (WLAN). 

At  the  receiver  the  Channel Estimation is used to recover the original information based upon certain estimation algorithm.

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