Collaborative filtering based on group coordinates for smoothing and directional sharpening
Research output: Chapter in Book/Report/Conference proceeding › Conference contribution › Scientific › peer-review
Details
| Original language | English |
|---|---|
| Title of host publication | ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing - Proceedings |
| Publisher | IEEE |
| Pages | 1573-1577 |
| Number of pages | 5 |
| ISBN (Print) | 9781467369978 |
| DOIs | |
| Publication status | Published - 4 Aug 2015 |
| Publication type | A4 Article in a conference publication |
| Event | IEEE International Conference on Acoustics, Speech and Signal Processing - Duration: 1 Jan 1900 → 1 Jan 2000 |
Conference
| Conference | IEEE International Conference on Acoustics, Speech and Signal Processing |
|---|---|
| Period | 1/01/00 → 1/01/00 |
Abstract
Groups of mutually similar image blocks are the key element in nonlocal image processing. In this work, the spatial coordinates of grouped blocks are leveraged in two distinct parts of the transform-domain collaborative filtering within the BM3D algorithm. First, we introduce an adaptive 1-D transform for 3-D collaborative filtering based on sampling 2-D smooth functions at the positions of grouped blocks. This adaptive transform is applied for improved decorrelation of the 2-D spectra of the grouped blocks. Second, we propose a directional sharpening procedure whose strength varies adaptively according to the relative orientation of the transform basis functions with respect to the group coordinates. Experiments confirm the efficacy of the proposed adaptations, for denoising as well as for sharpening of noisy images.
ASJC Scopus subject areas
Keywords
- adaptive transforms, BM3D, collaborative filtering, denoising, sharpening