Increasing Image Compression Rate using (DWT+DCT) and Steganography

The goal of image compression is to remove the redundancies for minimizing the number of bits required to represent an image while any type of compression like DWT, DCT, DFT, steganography works by embedding the secret data in redundancies of the image in invisibility manner. In this paper we increase image compression is done by hybrid (DCT+DWT) transform. MATLAB programs were written for DCT,DWT and DCT+DWT techniques and concluded based on the results obtained that DCT+DWT algorithm performs much better than the standalone JPEG-based DCT, DWT algorithm in term of peak signal to noise ratio (PSNR), as well as visual perception at higher compression ratio. . Finally, the results of the proposed method are compared with basic compression methods like DCT and DWT using three quality parameters. Simulation results demonstrate, that hybrid (DWT-DCT) along with steganography performs superior than individual JPEG-based DCT and DWT algorithms. The three quality metrics are: Peak Signal to Noise Ratio (PSNR), Compression Ratio (CR) and Storage Saving (SS). These metrics are used to measure the quality and quantity of compression results.