Speeding up the tile size transformation of wavelet transform coefficients in image data through partial retrieval of intermediate coefficients

摘要

Arbitrary tile sizes are allowed in JPEG2000 standard. But due to limitations in circuit and memory size, decodable tile size in mobile ports may be restricted. In such a scenario, tile size transformation in an intermediate gateway will be necessary while sending an image to a mobile port from another system. Algorithm in which tile size transformation of wavelet transform coefficients is done through retrieving pixels near the tile border and then correcting the coefficients for tiling has been proposed in the past. In this paper we will investigate the known approach of tiling through partial retrieval of intermediate wavelet coefficients rather than retrieving the pixels themselves. We will show that through this approach it is possible to speed up the tile size transformation process while limiting the noise below a permissible limit in both 5tap/3tap filter and 9tap/7tap filter. Improvement in PSNR through overflow correction in decoding is also discussed.