Computer Vision Foundations · 免费预览
可操纵滤波器
旋转至任意角度的滤波器，其响应可表示为少数几个基响应的固定线性组合，这便是可操纵定理；它将方向从滤波器组的一个维度转化为算术运算，从而在交汇处净化方向能量。
1. Rotations for free
Rotations for free
2. The theorem and the count
The theorem and the count
3. Oriented energy
Oriented energy
4. Junctions and their cleanup
Junctions and their cleanup
5. What steering buys
What does the steering theorem save compared to a dense bank of rotated filters?
6. The junction artifact
At a junction of two edges, raw oriented energy shows extra lobes beyond the two true orientations. What produces them and what removes them?
7. Steering weights
First-order steering uses g_theta = cos(theta) g_x + sin(theta) g_y. With cos(theta) = 0.6, write the coefficient multiplying g_y if sin(theta) = 0.8.