Comparative Performance of Embedded Coders at High Quality

The approach for still-image compression proposed by Said and Pearlman is designed initially for encoding the DWT coefficients. In this paper, the SPIHT scheme is used to encode the DCT coefficients. The DCT based scheme is computationally more efficient than the DWT based scheme. In order to improve the performances of our algorithm, we propose to increase the levels of resolution by increasing the DCT blocks size to 16×16, 32×32 and 64×64 instead of 8×8 as in standard JPEG. Experimented results show that the DCT based SPIHT provides high fidelity images, and it has been shown that these images are visually better than images reconstructed using other DCT-based coders for the same bit rate.