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Best wavelet packet bases in a rate-distortion sense
1Dept. of Electr. Eng., Columbia Univ., New York, NY.
Summary
A novel rate-distortion (R-D) optimal scheme efficiently codes adaptive trees using dynamic programming. This method reduces computational complexity for applications like wavelet packets and quadtrees.
Area of Science:
- * Information Theory
- * Computer Science
- * Signal Processing
Background:
- * Adaptive trees are crucial in data compression and signal processing.
- * Existing coding schemes can be computationally intensive.
- * Rate-distortion (R-D) optimization is key for efficient compression.
Purpose of the Study:
- * To present a fast, R-D optimal scheme for coding adaptive trees.
- * To ensure the scheme operates on the convex hull of the operational R-D curve.
- * To reduce the computational complexity of adaptive tree coding.
Main Methods:
- * Developed a dynamic programming pruning algorithm.
- * Applied the scheme to adaptive trees with disjoint and complete basis covers.
- * Utilized concepts from information theory and signal processing.
Main Results:
- * Achieved a fast R-D optimal coding scheme.
- * Significantly reduced computational complexity.
- * Demonstrated applicability to generalized multiresolution wavelet packet decomposition and DCT quadtrees.
Conclusions:
- * The proposed scheme offers an efficient solution for coding adaptive trees.
- * It provides a practical approach for advanced image processing applications.
- * The dynamic programming method enhances performance and reduces complexity.
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