Image Pyramids

Overview

The pyramid module provides multi-scale image access via the box-image-pyramid crate. Downsampled images allow detection of large radial features without requiring proportionally large voting radii.

PyramidWorkspace

PyramidWorkspace is a reusable buffer that avoids reallocating intermediate downsample storage on every frame. Construct it once, then call workspace.level(image, level) to extract a borrowed view at the requested pyramid level. Level 0 is the original resolution; each subsequent level halves both dimensions using a box filter.

#![allow(unused)]
fn main() {
let mut workspace = PyramidWorkspace::new();
let level2 = workspace.level(image, 2)?;
// level2.image() is an ImageView at 1/4 resolution
}

One-shot downsampling

For cases where workspace reuse is not needed, pyramid_level_owned extracts a single pyramid level as an owned image:

#![allow(unused)]
fn main() {
let downsampled = pyramid_level_owned(&image, 2)?;
}

Coordinate remapping

Pyramid levels track the scale factor so that detections at a downsampled level can be mapped back to the original image frame. OwnedPyramidLevel provides methods to remap Circle and Ellipse geometries to and from the level coordinate system.