Struct Snapshot 

pub struct Snapshot;

Snapshot comparison utilities.

Implementations

impl Snapshot

pub fn assert_match(name: &str, actual: &Image, threshold: f64)

Compare an actual image against a baseline snapshot.

Panics

Panics if the difference exceeds the threshold.

pub fn diff(a: &Image, b: &Image) -> f64

Calculate difference ratio between two images (byte-level).

pub fn perceptual_diff(a: &Image, b: &Image) -> f64

Calculate perceptual difference (color distance per pixel). Returns mean squared error normalized to 0.0-1.0.

pub fn generate_diff_image(a: &Image, b: &Image) -> Image

Generate a difference image highlighting changed pixels.

pub fn compare(a: &Image, b: &Image) -> ComparisonResult

Perform a comprehensive comparison between two images.

pub fn count_changed_pixels(a: &Image, b: &Image) -> u64

Count the number of pixels that differ between two images.

pub fn ssim(a: &Image, b: &Image) -> f64

Calculate Structural Similarity Index (SSIM).

Simplified implementation of SSIM that considers luminance similarity. Returns 1.0 for identical images, 0.0 for completely different.

pub fn compare_region( a: &Image, b: &Image, x: u32, y: u32, width: u32, height: u32, ) -> ComparisonResult

Compare a region of two images.

pub fn assert_region_match( name: &str, actual: &Image, baseline: &Image, x: u32, y: u32, width: u32, height: u32, threshold: f64, )

Assert that a region matches within threshold.

Panics

Panics if the region difference exceeds the threshold.