Struct PvsModel 

pub struct PvsModel;

Simplified psycho-visual sensitivity (PVS) model.

Provides a single visibility_threshold method that returns the minimum distortion energy that becomes just-noticeable to the human visual system (HVS) for a given luma level and spatial frequency.

The model is derived from the Watson (1993) DCTune formulation:

• Base threshold from the luma quantization table (frequency-dependent).
• Luminance masking multiplier: brighter or darker regions tolerate more distortion (Weber-Fechner / power-law masking).

Reference

Watson, A.B. (1993). DCTune.

Implementations

impl PvsModel

pub fn new() -> Self

Create a new PvsModel.

pub fn visibility_threshold(luma: f32, freq: f32) -> f32

Compute the visibility threshold (JND) for the given luma and frequency.

Parameters

• luma – mean luminance of the block, normalised [0.0, 1.0] (0 = black, 1 = white).
• freq – spatial frequency index in [0.0, 1.0] representing low (0) to high (1) frequency DCT coefficients. Linearly interpolated between the DC threshold and the highest AC threshold in the JPEG luma quantization matrix.

Returns

A positive threshold value. Distortions below this level are perceptually invisible; distortions above may be visible.

Trait Implementations

impl Clone for PvsModel

fn clone(&self) -> PvsModel

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for PvsModel

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

Formats the value using the given formatter.

impl Default for PvsModel

fn default() -> PvsModel

Returns the “default value” for a type.