Generating resized images using ripple free image filtering
US6816622B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 18, 2001 |
| Grant date | Nov 9, 2004 |
| Priority date | — |
| Expiry date | May 27, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2200/12
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An optimal filter kernel, formed by convolving a box filter with a filter of fixed integer width and unity area, is used to perform image resizing and reconstruction. The optimal filter has forced zeros at locations along a frequency scale corresponding to the reciprocal of the spacing of one or more pixels that comprise a source image to be resized. When a rescale value for a source image is selected, the optimal filter kernel is computed, mapped to the source image, and centered upon a location within the source image corresponding to the position of an output pixel to be generated. The number of pixels that lie underneath the optimal filter kernel is established by multiplying the number of pixels that comprise the width of the source image by the selected rescale value. Upon mapping the optimal filter kernel, the output pixel values that comprise the resized image are then evaluated by processing the one or more source image pixels, such as through interpolation. Alternatively, the output pixel values of the resized image are calculated by performing partial integral analysis with respect to a standard filter kernel of fixed width and unity area. The output pixel values are cal…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.