Struct ButteraugliParams 

pub struct ButteraugliParams { /* private fields */ }

Butteraugli parameters (from butteraugli).

Configure intensity target, HF asymmetry, and other parameters. Butteraugli comparison parameters.

Use the builder pattern to construct:

use butteraugli::ButteraugliParams;

let params = ButteraugliParams::new()
    .with_intensity_target(250.0)  // HDR display
    .with_hf_asymmetry(1.5)        // Penalize new artifacts more
    .with_compute_diffmap(true);   // Generate per-pixel difference map

Implementations

impl ButteraugliParams

pub fn new() -> ButteraugliParams

Creates a new ButteraugliParams with default values.

pub fn with_intensity_target(self, intensity_target: f32) -> ButteraugliParams

Sets the intensity target (display brightness in nits).

pub fn with_hf_asymmetry(self, hf_asymmetry: f32) -> ButteraugliParams

Sets the HF asymmetry multiplier. Values > 1.0 penalize new high-frequency artifacts more than blurring.

pub fn with_xmul(self, xmul: f32) -> ButteraugliParams

Sets the X channel multiplier.

pub fn with_compute_diffmap(self, compute_diffmap: bool) -> ButteraugliParams

Sets whether to compute the per-pixel difference map.

When true, the result will include an ImgVec<f32> difference map. When false (default), the diffmap field will be None, which is faster.

pub fn hf_asymmetry(&self) -> f32

Returns the HF asymmetry multiplier.

pub fn xmul(&self) -> f32

Returns the X channel multiplier.

pub fn intensity_target(&self) -> f32

Returns the intensity target in nits.

pub fn compute_diffmap(&self) -> bool

Returns whether to compute the per-pixel difference map.

pub fn with_single_resolution( self, single_resolution: bool, ) -> ButteraugliParams

Skip the half-resolution pass for faster approximate results.

The half-resolution pass contributes ~15% weight to the final diffmap. Skipping it saves ~25% of computation. Useful for encoder tuning loops where precise scores aren’t needed.

pub fn single_resolution(&self) -> bool

Returns whether single-resolution mode is enabled.

pub fn validate(&self) -> Result<(), ButteraugliError>

Validates that all parameter values are in acceptable ranges.

Called automatically by all public entry points. Returns an error if any parameter would cause division by zero, NaN propagation, or garbage results.

Errors

Returns ButteraugliError::InvalidParameter if:

• hf_asymmetry is not finite or not positive
• intensity_target is not finite or not positive
• xmul is not finite or is negative

Trait Implementations

impl Clone for ButteraugliParams

fn clone(&self) -> ButteraugliParams

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ButteraugliParams

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

Formats the value using the given formatter.

impl Default for ButteraugliParams

fn default() -> ButteraugliParams

Returns the “default value” for a type.