| 摘要 |
<p>A method of generating a motion vector with sub-pixel resolution associated with a first portion (10) of a first image frame (5) in a sequence of image frames for encoding the sequence of image frames is disclosed. An error surface represents a difference between image data of the first portion (10) of the first image frame (5) and image data of a second portion (20a-c) of a second image frame (15), displaced with a displacement vector (25a-c) in relation to the first portion (10), and is a function of the displacement vector (25a-c). The motion vector is an estimate of a displacement vector (25a-c) that minimizes the value of the error surface. The method comprises obtaining a coarse motion vector, which is an estimate of the motion vector with integer-pixel resolution. Furthermore, the method comprises approximating the error surface in a neighborhood of the coarse motion vector with a biquartic polynomial, and representing terms of the biquartic polynomial with orthogonal polynomials. Moreover, the method comprises generating the motion vector by searching for a displacement vector (25a-c) that minimizes said biquartic polynomial. A corresponding electronic apparatus, a corresponding computer program product, and a corresponding computer-readable medium are also disclosed.</p> |
