1 November 1992 Color image coding using variable blocksize vector quantization in (R,G,B,) domains
Author Affiliations +
Proceedings Volume 1818, Visual Communications and Image Processing '92; (1992) https://doi.org/10.1117/12.131468
Event: Applications in Optical Science and Engineering, 1992, Boston, MA, United States
Vector Quantization (VQ) is a popular image coding scheme with high data compression ratio. However, its major drawback is the edges in the reconstructed image are very poor if the codebook size isn't large enough. In this paper, we use the Variable Blocksize Vector Quantization (VBVQ) instead of a fixed blocksize VQ to code color images in the (R, G, B) domain. In order to alleviate block effect and preserve the edge well, we choose 4 X 4 X 3 as the largest block and 1 X 1 X 3 as the smallest block. For each blocksize we generate a codebook by using LBG's algorithm. The image is first decomposed into variable blocks and each block uses its corresponding codebook for vector quantization. In our simulation results, the bit rate is from 0.4 bpp (bit per pixel) to 1.1 bpp with PSNR (peak signal to noise ratio) of Y component from 28 db to 36 db. Our VBVQ outperforms conventional fixed blocksize 2 X 2 X 3 VQ with 512 codevectors in the codebook.
© (1992) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Ching-Yang Wang, Ching-Yang Wang, Long-Wen Chang, Long-Wen Chang, } "Color image coding using variable blocksize vector quantization in (R,G,B,) domains", Proc. SPIE 1818, Visual Communications and Image Processing '92, (1 November 1992); doi: 10.1117/12.131468; https://doi.org/10.1117/12.131468

Back to Top