Two Phase Image Compression Algorithm Using Diagonal Pixels of Image Blocks

Data compression is the way of reducing the number of bits required to store and efficiently utilize bandwidth during the transmission of data over a network channel. Image compression is also having importance as images contain important binary data to represent as image and that is to be stored and transmitted. The compression of an image must not reduce the quality of the image except in some cases. This paper proposes a compression algorithm with low PSNR, high fidelity images. The algorithm alienates the input image as non-overlapping blocks of size 4*4. Compression is achieved by using diagonally situated pixels and other adjacent pixels of the blocks. The decompression uses a simple approach. The diagonally situated pixels and other adjacent pixels are used to reconstruct images in decompression phase. The proposed algorithm reconstructs images with high fidelity at lower Peak Signal to Noise Ratio (PSNR). The results of proposed algorithm are compared with JPEG. Results have shown that at same PSNR values, reconstructed image quality by the proposed algorithm is better than that of the JPEG algorithm.