Add and evaluate reco methods

[heidemeissner]

First step: add reconstruction methods from WP2 plus interfaces to libertem Second step: Evaluate concerning:

• applicability and limitations of the algorithms
• performance analysis (parallelization, scalability)
• accuracy (e.g. robustness to noise)
• convergence to correct / unique solution (expected)
• applicability to interactive measurements ("online reconstruction")?
• data formats and data handling, e.g. zeroMQ, Check with WP1 colleagues

[heidemeissner]

Issue: uncertainties in raster point positions and positions of diffraction images due to shifts of beam and objects. Which algorithm is most robust?

[heidemeissner]

Check for further solvers of optimization problems, e.g. in Pytorch and tensorFlow. First step: define cost function

[heidemeissner]

Considered algorithms are:

• EPIE (DESY)
• EPIE (Achim)
• direct solver (phase lift)
• Kurato-Vicsek (added now, provided by Philippe Sünnen)
• PtyPy?
• Difference Map?
• Wirtinger Flow?
• (Blind) Wigner Deconvolution