| 摘要 |
Methods, software and devices are provided for designing scalable image FIR filters with integer coefficients. A template FIR filter is designed for the desired scaling operation. Then an ideal filter is designed from the template filter, and a suitable sample image is filtered, to produce a reference image. A scalable skeleton filter is designed, having integer coefficients and approximating the template FIR filter. A finite domain of integers is defined around each integer coefficient. This determines a finite universe of possible combinations of coefficients, and thus also respective available test filters. The available test filters are first screened for meeting an integer normalization requirement. Those that do not meet it within a tolerance are rejected. Then the screened test filters are ranked according to performance in terms of filter parameters. The sample image is filtered by each of the best ranked test filters, to produce test images. The test images are evaluated against the reference image by running a model for predicting visually perceptible differences. The test image that produces the fewest differences also determines which filter is chosen.
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