Struct Ssimulacra2Reference 

pub struct Ssimulacra2Reference { /* private fields */ }

Precomputed reference for repeated comparisons (from fast-ssim2).

Use this when comparing multiple distorted images against the same reference to avoid recomputing the reference image’s analysis. Precomputed SSIMULACRA2 reference data for fast repeated comparisons.

This struct stores precomputed data for the reference image at all scales, allowing you to quickly compare multiple distorted images against the same reference without recomputing the reference-side data each time.

For simulated annealing or other optimization where you compare many variations against the same source, this provides approximately 2x speedup.

Implementations

impl Ssimulacra2Reference

pub fn new<T>(source: T) -> Result<Ssimulacra2Reference, Ssimulacra2Error>

where T: ToLinearRgb,

Precompute reference data for the given source image.

Supports:

• imgref types (with the imgref feature): ImgRef<[u8; 3]>, ImgRef<[f32; 3]>, etc.
• yuvxyb types: Rgb, LinearRgb
• Custom types implementing ToLinearRgb

Errors

• If the image is smaller than 8x8 pixels

pub fn compare<T>(&self, distorted: T) -> Result<f64, Ssimulacra2Error>

where T: ToLinearRgb,

Compare a distorted image against the precomputed reference.

This is approximately 2x faster than calling compute_ssimulacra2 because it only needs to process the distorted image and compute cross-terms.

Errors

• If the distorted image dimensions don’t match the reference

pub fn width(&self) -> usize

Get the width of the original reference image.

pub fn height(&self) -> usize

Get the height of the original reference image.

pub fn num_scales(&self) -> usize

Get the number of scales that were precomputed.

Trait Implementations

impl Clone for Ssimulacra2Reference

fn clone(&self) -> Ssimulacra2Reference

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Ssimulacra2Reference

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

Formats the value using the given formatter.