TABLE II. Real Computing Time in Seconds for Computing a Single Sample With Selected Methods in 3D. PET-DDS Was Evaluated With 4 Gradient-Based Steps Per Diffusion Iteration, While Our Approach Was Used With NMLEM=21 (Corresponding to Images in Fig. 12). Timings Include Constructing the Likelihood Schedule With 21 Steps of MLEM for Our Approach.
| Method | Time (s) | |
|---|---|---|
| 25 SGM steps | 100 SGM steps | |
| MLEM | 33 | 33 |
| PET-DDS with single SGM | 116 | 398 |
| PET-DDS with perp. SGMs | 137 | 488 |
Ours (
 ) |
145 | 385 |
Ours (
 ) |
126 | 369 |
Ours (
 ) |
116 | 368 |