Name
Abstract | ||
|---|---|---|
Changing resolution of images is a common operation. It is also common to use simple, i.e., small interpolation ker- nels satisfying some îsmoothnessî qualities that are deter- mined in the spatial domain. Typical applications use lin- ear interpolation or piecewise cubic interpolation. These are popular since the interpolation kernels are small and the results are acceptable. However, since the interpolation kernel, i.e., the impulse response, has a nite, and small length, the frequency domain characteristics are not good. Therefore, when we enlarge the image by a rational factor of , aliasing effects usually appear and cause a no- ticeable degradation in quality of the image. One such ef- fect is jagged edges. Another effect is low frequency mod- ulation of high frequency components such as sampling noise. Enlarging an image by a factor of , is rep- resented by rst interpolating the image on a grid times ner than the original sampling grid, and then resampling it every grid points. While the usual treatment of the alias- ing created by the resampling operation is aimed towards improving the interpolation lter in the frequency domain, this paper suggests reducing the aliasing effects using a polyphase representation of the interpolation process, and treating the polyphase lters separately. We discuss sepa- rable interpolation and so the analysis is conducted for the one-dimensional case. Finally, we compare a 6 coefcient polyphase lters found using the suggested procedure with a 6 coefcient polyphase lters capable of reconstructing a 3rd order polynomial. |
Year | Venue | Keywords |
|---|---|---|
2003 | SIP | polyphase lters.,resampling,enlargement,interpolation,antialiasing,low frequency,high frequency,satisfiability,frequency domain,impulse response |
Field | DocType | Citations |
Frequency domain,Polyphase system,Spline interpolation,Impulse invariance,Computer science,Interpolation,Algorithm,Electronic engineering,Aliasing,Linear interpolation,Piecewise | Conference | 0 |
PageRank | References | Authors |
0.34 | 4 | 1 |
Name | Order | Citations | PageRank |
|---|---|---|---|
| Daniel Seidner | 1 | 3 | 0.91 |