| This covers both basic Theory and NPAC projects with examples |
| Wavelet compression activity: goals |
| Compression of still images: |
| improving quality for fixed bitrate |
| decreasing encoding time (currently encoding still image takes 2 seconds on SGI Challenge; similar problem exists for DCT like H.263 based systems - currently no real-time encoding exists in software) |
| parallelizing: decomposition, quantization and arithmetic coding (important in view of emergence of multiprocessor PentiumPro systems) |
| Compression of video: |
| we verified that motion estimation in wavelet space does not work |
| plan: hybrid video method |
| Web and other functionalities: |
| progressive still image plug-in (implemented) |
| in progress - zoom, local window, chroma key |
| plans: transparency, pre- and post-processing, access key file protection, error recovery |
001 Wavelet compression (1) Czeslaw Jedrzejek, Tomasz Major
002 Wavelet compression (2)
003 Wavelet compression (3)
004 Wavelet compression (4): Algorithm
005 Wavelet compression (5)
006 Compression(6): Wavelet decomposition
007 Compression(7): Reorganization of wavelet trees into wavelet
blocks
008 Compression (8): Principle of zerotree quantization
009 Compression (9): Choice of filter normalization
010 Compression (10): Statistics of zerotrees in subbands vs pass
number for Lenna
011 Compression (11): Motion Estimation in Real Space - Block Matching
012 Compression (12): Multiresolution Motion Estimation (1)
013 Compression (13): Implementation of Multiresolution Motion
Estimation (2)
014 Compression (14): Multiresolution Motion Estimation (3)
015 Compression (15): Coding of I-Frame
016 Compression (16): Demonstration of deficiency of motion estimation
scheme in wavelet space
017 Compression (17): Compensated frame
018 Compression (18): Wavelet decomposition of frame #1
019 Compression (19): Wavelet decomposition of frame #2
020 Compression (20): Conclusion
021 Compression (21): Hybrid wavelet video encoder