Name
Abstract | ||
|---|---|---|
In this work we demonstrate the relationship existing between two important issues in vision: multi-scale local spectrum analysis, and log-polar foveatization. We show that, when applying a continuous set of self-similar (rotated and scaled) band-pass filters to estimate the local spectrum at a given point of attention of the image, the inverse Fourier transform of this local spectrum is a log-polar foveated version of the original image at that position. Both the local spectrum and its associated foveated image can be obtained through log-polar warping of the spectral/spatial domain followed by a conventional invariant low-pass filtering and the corresponding inverse warping. Furthermore, the low-pass filters in the warped space and frequency domains are mirror versions of each other. Thus, filters with mirror symmetry under the log-polar warping are self-dual, and make the foveatization process commute with the Fourier transform, Nevertheless, in order to implement a fovea that can be easily moved across the image, it is preferable to use a fixed bank of steerable filters, instead of applying log-polar warpings with different centers. Using low-pass scalable filters we have implemented a real-time moving fovea. We believe that a dual finite spatial/spectral local representation of images could be a very powerful tool for many visual tasks, which could benefit from a dual explicit representation in space and spatial frequency, as well as from the rotation and scale invariance naturally achieved in both domains. |
Year | DOI | Venue |
|---|---|---|
1998 | 10.1117/12.320121 | HUMAN VISION AND ELECTRONIC IMAGING III |
Keywords | Field | DocType |
spectrum,mirror symmetry,real time,band pass filter,fourier transform,low pass filter,spectrum analysis,spatial frequency,fourier transforms,vision,scale invariance,bandpass filters,frequency domain,spatial frequencies,low pass | Computer vision,Signal processing,Image warping,Machine vision,Filter (signal processing),Image processing,Optics,Fourier transform,Invariant (mathematics),Artificial intelligence,Spatial frequency,Physics | Conference |
Volume | ISSN | Citations |
3299 | 0277-786X | 1 |
PageRank | References | Authors |
0.64 | 7 | 3 |
Name | Order | Citations | PageRank |
|---|---|---|---|
| rafael navarro | 1 | 1 | 0.98 |
| Javier Portilla | 2 | 822 | 90.02 |
| antonio tabernero | 3 | 86 | 11.45 |