Struct AlternatingProjection 

pub struct AlternatingProjection {
    pub iterations: usize,
    pub object_step: f64,
    pub batch_size: usize,
    pub epsilon: f64,
    pub loss_type: LossType,
}

Alternating-projection reconstruction for Fourier ptychographic microscopy.

Method

For each measured frame, the algorithm extracts the corresponding patch of the current high-resolution object spectrum, multiplies it by the pupil, and propagates the resulting field to the detector plane. It replaces the predicted detector amplitude with the measured amplitude while retaining the predicted phase, propagates the corrected field back to Fourier space, and inserts the resulting correction into the object spectrum. Repeating this operation over overlapping Fourier patches makes them converge toward a mutually consistent complex object.

For incoherently multiplexed frames, one measured-to-predicted amplitude ratio is applied jointly to every source mode before their corrections are back-projected.

Reference

G. Zheng, R. Horstmeyer, and C. Yang, “Wide-field, high-resolution Fourier ptychographic microscopy” (2013), Nature Photonics 7, 739–745.

Fields

iterations: usize

Number of complete passes through the acquisition schedule.

object_step: f64

Relaxation factor applied to each object-spectrum correction.

batch_size: usize

Number of measured frames supplied to each reconstruction step.

epsilon: f64

Positive numerical floor used in divisions and dark-field handling.

loss_type: LossType

Loss used for diagnostics; the projection itself always enforces the measured amplitude.

Implementations

impl AlternatingProjection

pub fn iterations(self, iterations: usize) -> Self

Sets the number of complete acquisition-schedule passes; validation requires non-zero.

pub fn object_step(self, object_step: f64) -> Self

Sets the finite positive relaxation applied to object-spectrum corrections.

pub fn batch_size(self, batch_size: usize) -> Self

Sets the positive number of acquisition frames supplied per step.

Trait Implementations

impl Clone for AlternatingProjection

fn clone(&self) -> AlternatingProjection

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for AlternatingProjection

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for AlternatingProjection

fn default() -> Self

Returns the “default value” for a type.

impl ReconstructionAlgorithm for AlternatingProjection

type IterationMetrics = NoIterationMetrics

Algorithm-specific metrics emitted by each step and appended to the trace.

fn validate(&self) -> Result<()>

Validates solver parameters independently of a reconstruction problem.

fn step<M: MeasurementRead>( &mut self, problem: &ReconstructionProblem<M>, state: &mut ReconstructionState, batch: &Batch, _iteration: usize, ) -> Result<StepOutput<Self::IterationMetrics>>

Updates state for one scheduled batch in zero-based iteration.

fn iterations(&self) -> usize

Returns the requested number of complete schedule passes.

fn batch_size(&self) -> usize

Returns the number of measured frames combined into one step.

fn validate_problem<M: MeasurementRead>( &self, _problem: &ReconstructionProblem<M>, ) -> Result<()>

Validates solver requirements that depend on problem.

fn initialize<M: MeasurementRead>( &self, problem: &ReconstructionProblem<M>, ) -> Result<ReconstructionState>

Creates the default CPU-backed state for problem.

fn initialize_with_backend<M: MeasurementRead>( &self, problem: &ReconstructionProblem<M>, backend: Arc<dyn Backend>, ) -> Result<ReconstructionState>

Creates reconstruction state using the supplied execution backend.

fn canonicalize_state<M: MeasurementRead>( &self, _problem: &ReconstructionProblem<M>, _state: &mut ReconstructionState, ) -> Result<()>

Projects algorithm-owned ambiguities into a stable reported convention.

fn supports_joint_reconstruction(&self) -> bool

Reports whether the algorithm may run inside physical joint calibration.

fn run<M: MeasurementRead>( self, problem: &ReconstructionProblem<M>, ) -> Result<ReconstructionResult>

where Self: Sized,

Runs the algorithm with default sequential scheduling and no callbacks.

fn run_with_callbacks<M: MeasurementRead>( self, problem: &ReconstructionProblem<M>, callbacks: Vec<Box<dyn Callback>>, ) -> Result<ReconstructionResult>

where Self: Sized,

Runs the algorithm and invokes callbacks at their declared hooks.

fn run_from_checkpoint<M: MeasurementRead>( self, problem: &ReconstructionProblem<M>, checkpoint: ReconstructionCheckpoint, ) -> Result<ReconstructionResult>

where Self: Sized,

Resumes a run from a checkpoint after validating it against problem.