Fundamentals Of Image Compression & Comparative Study Of Relative Study Of JPEG & Hybrid(DWT+DCT) Model

摘要

In this paper we have discussed the fundamentals of image compression and compared the results of JPEG and a Hybrid model. In hybrid model we have used DWT (Discrete Wavelet Transform) and DCT (Discrete cosine Transform) for transform mapping. As we know that DWT has its multi resolution property which is helpful for image compression. As in JPEG 2000 also DWT is used but EBCOT (Embedded Block Code for Optimal Truncation) coding has high computational complexity. For JPEG we have taken results for different quality factor values and for hybrid model also we have taken results for different quality factor values and compared it is observed that for very less variation in PSNR value compression ratio has increased considerably.