Title :
An adaptive DCT coding with edge based classification
Author_Institution :
Tsukuba Res. & Dev. Center Ltd., Texas Instrum., Tsukuba, Japan
Abstract :
Discrete cosine transform (DCT) coding has been proven to be an efficient means of image compression coding. A lot of effort has been made to improve the coding efficiency of DCT based coding. This paper presents an adaptive DCT coding based on edge information. This scheme is designed to properly exploit the correlation between edge direction and distribution of DCT coefficients. Edges are extracted from the original image first. Then sub-optimal block size and scanning order are determined at each block based on the extracted edges. This way an adaptive DCT scheme taking account of local characteristics of the image can be achieved. It is shown through simulations that the proposed algorithm outperforms a conventional coding scheme in terms of coding efficiency by about 15%
Keywords :
adaptive codes; data compression; discrete cosine transforms; edge detection; image classification; image coding; transform coding; adaptive DCT coding; coding efficiency; discrete cosine transform coding; edge based classification; edge direction; edge extraction; image coding; image compression; scanning order; sub-optimal block size; Adaptive signal processing; Australia; Data mining; Discrete cosine transforms; Discrete transforms; Encoding; Image coding; Instruments; Quantization; Signal processing algorithms;
Conference_Titel :
Signal Processing and Its Applications, 1999. ISSPA '99. Proceedings of the Fifth International Symposium on
Conference_Location :
Brisbane, Qld.
Print_ISBN :
1-86435-451-8
DOI :
10.1109/ISSPA.1999.818118
