Computer Vision Foundations · 免费预览
二维采样
一般的网格矩阵描述平面上的采样；六角点阵可使每个采样点多获得约百分之十的无混叠带宽，生物学中也会用到；而采样要求使用抗混叠预滤波器。
1. Grids are matrices
Grids are matrices
2. The hexagon wins
The hexagon wins
3. Prefilter before you sample
Prefilter before you sample
4. Sampling in space-time
Sampling in space-time
5. Why hexagons beat squares
Why does a hexagonal sampling grid achieve roughly ten percent higher alias-free resolution per sample than a square grid for natural images?
6. The prefilter's honest cost
Decimation without a prefilter produced new stripes on a zebra. What does antialiasing prefiltering cost and what does it save?
7. The hexagonal gain
Write the approximate percentage of resolution a hexagonal grid gains over a square grid at the same alias-free bandwidth. Write the number only.