Wavelet based hybrid image coding scheme

This paper describes a computationally efficient hybrid image coding scheme. The proposed hybrid coding scheme combines the advantages of simple hardware complexity of the block discrete cosine transform coding and the high performance of the embedded zerotree discrete wavelet transform coding. It is based on the following five key features: (1) one-scale discrete wavelet transform of the input image resulting in four subband images (LL, LH, HL and HH), (2) block discrete cosine transform coding of the LL band image, (3) nonlinear transformations of the residual image of the LL band, the LH, HL and HH images, (4) generation of zerotree structure of the nonlinearly transformed coefficients, and (5) lossless data compression via adaptive arithmetic coding of the zerotree structured data.