Abstract
In this paper, the Lapped Orthogonal Transform (LOT) with unequal length basis function is considered. The proposed unequal length LOT (ULLOT) has both long basis of length 2A/ and short basis of length M, while the lengths of all bases of the conventional LOT are 2JU. A new class of LOT can be constructed with some modifications of Malvar's Fast LOT. Therefore, the fast algorithm for the Discrete Cosine Transform (DOT) will surely facilitate the computation of the ULLOT. Although the computational complexity of the ULLOT is always lower than that of the LOT, there exist some cases where the coding gain of the ULLOT becomes slightly higher than that of the LOT. Its ability to reduce ringing artifacts is an attractive feature as well. The size-limited structure for the finite length signal is investigated and the ULLOTs are tested on image coding application. The simulation results confirm the validity of the proposed ULLOT.
| Original language | English |
|---|---|
| Pages (from-to) | 825-834 |
| Number of pages | 10 |
| Journal | IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences |
| Volume | E82-A |
| Issue number | 5 |
| Publication status | Published - 1999 |
| Externally published | Yes |
Keywords
- Fast algorithm
- Lapped transform
- Subband image coding
ASJC Scopus subject areas
- Signal Processing
- Computer Graphics and Computer-Aided Design
- Electrical and Electronic Engineering
- Applied Mathematics