COMPARATIVE ANALYSIS OF JPEG COMPRESSION AND FRACTAL IMAGE COMPRESSION FOR MEDICAL IMAGES

摘要

The need for bulk storage of Medical Images with efficient utilization of the bandwidth during transmission of images, calls for an effective image Compression technique. The use of digital image data offers additional advantage as the images can be stored and analyzed .There are many compression techniques available They are lossy and lossless image compressions. Lossy compression schemes are irreversible while the lossless compression schemes are reversible. Lossy compression schemes are JPEG compression which is achieved using Discrete cosine transform (DCT) ,JPEG 2000 achieved using Discrete Wavelet transform( DWT) and Fractal Image Compression(FIC) achieved using affine transform. The quality of the images is analyzed through objective analysis and subjective analysis. Objective analysis of Images are performed by analyzing the images through various quality measures like Peak signal to Noise ratio,(PSNR),compression Ratio(CR),Mean square Error(MSE) while subjective analysis of images vary from person to person in the perception of images. This paper aims in providing a comparative analysis of JPEG compression and Fractal Image compression for medical images like Magnetic resonance image of Brain using various Images transforms such as DCT, DWT and affine transforms based on the performance measures. The simulated results implemented on mat lab showed that Fractal Image compression has better performance measures when compared to JPEG compression with regard to PSNR and Fractal Image compression takes less encoding time when compared to JPEG 2000.