Performance Comparison of Block-DCT, Kekre’s Wavelet and Haar Transform using LZW and Huffman Encoding in Image Steganography

This paper proposes the use of various transforms for image steganography. It focuses on use of wavelet transform such as Kekre’s Wavelet and Haar transform to compress cover image and use of compression mechanisms such as LZW for secret image. Wavelet transform is generated from their respective orthogonal transform. Image Steganography is the art of hiding information into a co4ver image. A novel technique for image steganography using transforms such as Kekre’s wavelet transform and Haq3ar transform along with LZW is used to convert original image (cover image) from spatial domain to frequency domain. In the proposed methodology the secret message is encoded using LZW technique. Then encrypted image/message is embedded in the transformed carrier image. The experimental results show the comparative results between Huffman coding and LZW compression using Kekre’s Wavelet t4ransform, Haar transform and DCT. Moreover PSNR and RMSE between the cover image and stego image shows the better results in comparison with other existing steganography approaches. The perceptual difference between the stego image and original image is imperceptible to human eye. The results show an improvement over PSNR and MSE compared to the existing approach. Further high security is maintained since the secret message/image cannot be extracted without knowing decoding rules and Decoding table