Table 1: Comparison of two sampling methods.

Objects and sizes Head 512 × 512 × 295 Heart 512 × 512 × 41 Spacing (mm × mm × mm) 0.486 × 0.486 × 0.700 0.318 × 0.318 × 2.000 Sampling distance (mm) 0.3 0.3 Time by the traditional (s) 58.274 7.192 Time by the proposed (s) 17.158 2.043 Acceleration rate 3.606 3.52