| Operation | Input angles | Symmetries | Method | Interpolation | Weighting | Notes | Source code |
|---|---|---|---|---|---|---|---|
| 'BP 3F', 'BP 32F' | 3 | + | Direct Fourier | 5x5x5 Keiser-Bessel | - | 1 or 3 output volumes, MPI available | wiw3d.f wiw32d.f |
| 'BP CG' | 3 | - | SIRT - Conjugate gradient | - | - | MPI available | repcg.f, prepcub_s.f, hiang.f, rprq.f, prjcq.f, bckcq.f |
| 'BP RP' | 3 | + | SIRT - Constrained | - | - | MPI available | reps.f, redprq.f, hiang.f, asta.f, bckcq.f, prjcq.f |
| 'BP 3G' | 3 | + | Direct Fourier | Non-uniform (gridded) Fourier | - | - | wiw3g.f |
| 'BP 3N' | 3 | + | Direct Fourier | Nearest neighbor | - | -- | nn4.f |
| 'BP 3D' | 3 | - | WBP | - | Choice of: Gaussian, none, triangular overlap | For tomography | bcq.f, buildm.f, cang.f, bpcqp.f, bpcmp.f, bpcq.f, bpcm.f, wtf.f, wtm.f |
| 'BP W2' | Single | - | WBP | - | Parzen | For tomography. Faster then 'BP S2'. | wgbp2.f, rdpa.f, fftr_q.f |
| 'BP S2' | Single | - | SIRT - Constrained. | - | - | For tomography. Slower than 'BP W2' | bps2.f, bpcq.f, prjs2.f, prjc2.f, prjc0.f, repr2_s.f, cppb.f, smt3.f, ... |
| 'BP R2' | None | - | - | R**2 or R*, Parzen | --- | Weights only, No back projection! Use with 'BP RP'. | bpwr.f, bpwr_q.f |
Source file: bp_overview.html Updated: 17 Sept. 2009 ArDean Leith