A new wavelet-based measure of image focus
نویسندگان
چکیده
We present a new measure of image focus. It is based on wavelet transform of the image and is defined as a ratio of high-pass band and low-pass band norms. We show this measure is monotonic with respect to the degree of defocusation and sufficiently robust. We experimentally illustrate its performance on simulated as well as real data and compare it with existing focus measures (gray-level variance and energy of Laplacian). Finally, an application of the new measure in astronomical imaging is shown. 2002 Elsevier Science B.V. All rights reserved.
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ورودعنوان ژورنال:
- Pattern Recognition Letters
دوره 23 شماره
صفحات -
تاریخ انتشار 2002