Still color Image Compression Based on 3-D DCT
Xu Ding · 2003
In this paper, A three dimensional discrete cosine transform(3D DCT) coder for still color images is presented, which can not only achieve high compression ratio but also ensure good image quality. In the proposed method, the original image is splitted into non overlapped 8×8 blocks and segments subblocks of the image into four different classes based on local energy magnitude. Then those subblocks with the same class are gathered to form 3D cuboids, and employs 3D DCT to the 3D cuboids. This improves the efficiency of compression.Computer simulation results show that the PSNR (average Peak Signal Noise Ratio) of reconstructed images achieve 29dB with high fidelity when the compression ratios are higher than 40. Compared to JPEG, it advances more than 5dB in the same situation. The proposed method achieves higher fidelity of decoded images than by JPEG.