Fractal Image Compression Using Quad Tree Decomposition & DWT

Er. Chetan, Er. Deepak Sharma

Abstract: Image compression plays an important role in our day to day activities. Image compression is the process of reducing the amount of data required to represent given quantity of information in image to reduce storage requirements and many other reasons. In a computer image is represented as an array of numbers, integers and is known as digital image. Image array is mainly of two dimensional and three dimensional, if the image is two dimensional than the image is black and white and if image is colour than it is three dimensional. Fractal Image Compression is an approach for better image compression. The main objective of this method is to provide simple and better compression results, which is based on proposed Quad tree Decomposition and Discrete Wavelet Transform method for a color image. Fractal image compression can be obtained by dividing the ycbcr image into unoverlapped blocks depending on a quantization value and the well known techniques of Quad tree decomposition. The compression ratio (CR) and Peak Signal to Noise Ratio (PSNR) values are determined for three types of images namely standard Lena image, Baboon image and Pepper image.

Keywords: RGB color model, DWT, Quad tree decomposition, CR, PSNR.