Struct ContentSignature 

pub struct ContentSignature { /* private fields */ }

Compact content fingerprint over the whole watched region: a 4x4 grid of sub-cell mean lumas plus a contrast byte (the same signature the stability mask compares blocks with, scaled to the region).

Emits the signature as lowercase hex DetectorOutput::Text. Comparison is tolerance-aware and ANCHORED: while the current signature stays within tolerance of the last changed-to content (fewer than two components moving beyond it), the previous output is re-emitted verbatim — capture jitter and sub-tolerance drift can never fire Changed events, and there is no quantization-boundary flicker.

Implementations

impl ContentSignature

pub fn new() -> Self

pub fn tolerance(self, tol: u8) -> Self

Per-component comparison tolerance on the 0-255 signature bytes (default 10). At least two components must exceed it for the fingerprint to count as changed.

Trait Implementations

impl Default for ContentSignature

fn default() -> Self

Returns the “default value” for a type.

impl Detector for ContentSignature

fn evaluate( &mut self, view: &FrameView<'_>, ) -> Result<DetectorOutput, DetectorError>

fn is_heavy(&self) -> bool

Heavy detectors (OCR, ML inference) are routed to the blocking thread pool by the watcher loop so they never stall the async scheduler. Cheap pixel-math detectors keep the default false.