Filtering requirements for gradient-based optical flow measurement
نویسنده
چکیده
The accuracy of gradient-based optical flow algorithms depends on the ability to measure intensity gradients accurately. We show how the temporal gradient can be compromised by temporal aliasing arising from motion and how appropriate post-sampling spatial filtering improves the situation. We also demonstrate a benefit of using higher-order gradient estimators.
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ورودعنوان ژورنال:
- IEEE transactions on image processing : a publication of the IEEE Signal Processing Society
دوره 9 10 شماره
صفحات -
تاریخ انتشار 2000