Optimal Quantization Scheme for Biorthogonal Wavelets for Coding and Data hiding 台北科技大學資工所 指導教授：楊士萱 研究生：廖武傑 2003/2/27
Outline Motivation Filter implementation Experimental results Future work
Motivation The difference of between 9/7 and other filters for JPEG-2000 is small, but it is significant for SPIHT. Can we modify the coding algorithm to make other filters (such as 5/3) to achieve better performance?
Difference between JPEG2000 and SPIHT No inter-scale correlation is employed in JPEG SPIHTJPEG-2000 Better entropy coding and more wavelet- independent quantization are employed in JPEG
Key point to SPIHT Coding efficiency Orthogonality -NOM (near-orthogonality measure ) Zero-tree -energy compaction
Outline Motivation Filter implementation Experimental results Future work
Filter-bank implementation Lifting-Based Filtering: Convolution-Based Filtering: Dot products between the two filter masks and the signal.
Filter-bank implementation M. D. Adams and F. Kossentini, “Reversible integer to integer wavelet transforms for Image compression: performance evaluation and analysis” IEEE Trans. Image processing, Jun we’ve implemented lifting-based filters:5/3, 9/7-F, 9/7-M, 5/11-A, 5/11-C, 13/7-T, 13/7-C, 2/6, 2/10, 6/14 and convolution-based filter:9/7, 10/18, haar, D4, D6.
Outline Motivation Filter implementation Experimental results Future work
SPIHT coding efficiency(”Lena”) bpp5/39/7-F9/7-M5/11-A5/11-C13/7-C13/7-T bpp2/62/106/ Lifting scheme:
SPIHT coding efficiency(cont.) Bpp10/189/75/3D_6D_4Haar convolution scheme:
Energy distribution(5/3,”Lena”) Lifting scheme, 5 level decomposition, level5-level3
Energy distribution(9/7-F,”Lena”) Lifting scheme, 5 level decomposition, level5-level3
Coding performance at various scaling 5/3,”Lena” scaling
Coding performance at various scaling 9/7-F,”Lena” scaling
Outline Motivation Filter implementation Experimental results Future work
Modify the scaling constant for biorthogonal wavelets to achieve better performance. Experiment for data hiding. (such as DWT domain watermarking).