A Novel Approach to Enhance Robustness in Steganography Using Multiple Watermark Embedding Algorithm

This paper deals with an enhanced technique that improves robustness in steganography. A multiple watermark embedding algorithm has been proposed to embed multiple text messages as watermarks simultaneously in the same watermark space while minimizing the watermark (distortion) energy. The watermark is embedded in the DCT coefficients of the green channel of the color image. The algorithm takes into account the perceptual capacity of each coefficient inside the DCT blocks before embedding the watermark information. Therefore, the first 16 low frequency coefficients (excluding the DC value) in the 8×8 DCT block was screened and the eight coefficients with the maximum magnitudes were selected for embedding. The algorithm used is blind and does not require the original image for extracting the watermark. The watermarking method is robust against JPEG compression, additive noise, cropping, scaling, low-pass and median filtering.