Crate radsym 

radsym

Radial symmetry detection library: center proposal generation, local circular and elliptical support analysis, support scoring, and local image-space refinement. CPU-first, deterministic, composable tools.

Quick start

The one-call detect_circles runs the whole propose-score-refine pipeline. Configure it with the DetectCirclesConfig::for_radii builder:

use radsym::{detect_circles, DetectCirclesConfig, ImageView, Polarity};

// 1. Load or create an image (here: synthetic bright disk)
let size = 64;
let mut data = vec![0u8; size * size];
for y in 0..size {
    for x in 0..size {
        let dx = x as f32 - 32.0;
        let dy = y as f32 - 32.0;
        if (dx * dx + dy * dy).sqrt() <= 10.0 {
            data[y * size + x] = 255;
        }
    }
}
let image = ImageView::from_slice(&data, size, size).unwrap();

// 2. Detect circles in a single call.
let config = DetectCirclesConfig::for_radii([9, 10, 11])
    .polarity(Polarity::Bright)
    .radius_hint(10.0)
    .min_score(0.2);
let detections = detect_circles(&image, &config).unwrap();

// 3. Inspect the results (sorted by descending support score).
for detection in &detections {
    println!(
        "center=({:.1}, {:.1}) r={:.1} score={:.3}",
        detection.hypothesis.center.x,
        detection.hypothesis.center.y,
        detection.hypothesis.radius,
        detection.score.total,
    );
}
assert!(!detections.is_empty());

Power users can still drive the propose-score-refine stages directly with compute_gradient, frst_response, extract_proposals, score_circle_support, and refine_circle. To inspect why proposals were accepted or rejected, use detect_circles_with_diagnostics.

Modules

• core — fundamental types, image views, geometry, gradient, NMS, homography, circle fitting
• propose — center-proposal generation (FRST, RSD, homography-aware)
• support — local support extraction and scoring
• refine — local hypothesis refinement (Parthasarathy radial center, iterative circle/ellipse, homography-aware ellipse)
• diagnostics — visualization: heatmaps, overlays

Feature flags

• rayon — parallel execution for multi-radius proposals
• image-io — load images via the image crate
• tracing — structured logging
• affine — experimental affine-aware extensions (GFRS)
• serde — serialization support

Re-exports

pub use crate::core::coords::PixelCoord;

pub use crate::core::error::RadSymError;

pub use crate::core::error::Result;

pub use crate::core::geometry::Annulus;

pub use crate::core::geometry::Circle;

pub use crate::core::geometry::Ellipse;

pub use crate::core::geometry::Rect;

pub use crate::core::gradient::GradientField;

pub use crate::core::gradient::GradientOperator;

pub use crate::core::gradient::SourcePixel;

pub use crate::core::gradient::compute_gradient;

pub use crate::core::gradient::compute_gradient_f32;

pub use crate::core::gradient::scharr_gradient;

pub use crate::core::gradient::scharr_gradient_f32;

pub use crate::core::gradient::sobel_gradient;

pub use crate::core::gradient::sobel_gradient_f32;

pub use crate::core::gradient::thin_gradient;

pub use crate::core::homography::Homography;

pub use crate::core::homography::RectifiedGrid;

pub use crate::core::homography::rectified_circle_to_image_ellipse;

pub use crate::core::image_view::ImageView;

pub use crate::core::image_view::OwnedImage;

pub use crate::core::nms::NmsConfig;

pub use crate::core::polarity::Polarity;

pub use crate::propose::extract::ResponseMap;

pub use crate::propose::extract::extract_proposals;

pub use crate::propose::extract::suppress_proposals_by_distance;

pub use crate::propose::frst::FrstConfig;

pub use crate::propose::frst::FrstTuning;

pub use crate::propose::frst::ScaledResponse;

pub use crate::propose::frst::frst_response;

pub use crate::propose::frst::frst_response_fused;

pub use crate::propose::frst::frst_response_scaled;

pub use crate::propose::homography::HomographyProposal;

pub use crate::propose::homography::HomographyRerankAdvanced;

pub use crate::propose::homography::HomographyRerankConfig;

pub use crate::propose::homography::RectifiedResponseMap;

pub use crate::propose::homography::RerankedProposal;

pub use crate::propose::homography::extract_rectified_proposals;

pub use crate::propose::homography::frst_response_homography;

pub use crate::propose::homography::rerank_proposals_homography;

pub use crate::propose::remap::remap_proposal_to_image;

pub use crate::propose::remap::remap_proposals_to_image;

pub use crate::propose::rsd::RsdConfig;

pub use crate::propose::rsd::rsd_response;

pub use crate::propose::rsd::rsd_response_fused;

pub use crate::propose::seed::Proposal;

pub use crate::propose::seed::ProposalSource;

pub use crate::propose::seed::SeedPoint;

pub use crate::support::annulus::AnnulusSamplingConfig;

pub use crate::support::score::ScoringConfig;

pub use crate::support::score::SupportScore;

pub use crate::support::score::score_circle_support;

pub use crate::support::score::score_circle_support_detailed;

pub use crate::support::score::score_ellipse_support;

pub use crate::support::score::score_ellipse_support_detailed;

pub use crate::support::score::score_rectified_circle_support;

pub use crate::support::score::score_rectified_circle_support_detailed;

pub use crate::refine::circle::CircleRefineAdvanced;

pub use crate::refine::circle::CircleRefineConfig;

pub use crate::refine::circle::refine_circle;

pub use crate::refine::ellipse::EllipseRefineAdvanced;

pub use crate::refine::ellipse::EllipseRefineConfig;

pub use crate::refine::ellipse::refine_ellipse;

pub use crate::refine::homography::HomographyEllipseRefineAdvanced;

pub use crate::refine::homography::HomographyEllipseRefineConfig;

pub use crate::refine::homography::HomographyRefinementResult;

pub use crate::refine::homography::refine_ellipse_homography;

pub use crate::refine::radial_center::RadialCenterConfig;

pub use crate::refine::radial_center::radial_center_refine;

pub use crate::refine::radial_center::radial_center_refine_from_gradient;

pub use crate::refine::result::RefinementResult;

pub use crate::refine::result::RefinementStatus;

pub use crate::pipeline::CircleDetection;

pub use crate::pipeline::DetectCirclesAdvanced;

pub use crate::pipeline::DetectCirclesConfig;

pub use crate::pipeline::Detection;

pub use crate::pipeline::detect_circles;

pub use crate::pipeline::detect_circles_with_diagnostics;

Modules

core

Fundamental types, image views, geometry, gradient computation, and NMS.

diagnostics

Visualization and diagnostic export.

pipeline

High-level detection pipeline.

prelude

Convenience re-exports for common workflows.

propose

Center-proposal generation.

refine

Local image-space hypothesis refinement.

support

Local support extraction and scoring.