Chain together components for Canny edge detection

src/filter.rs

@@ -1,3 +1,5 @@
+pub mod canny;
 pub mod sobel;
 
+pub use canny::canny;
 pub use sobel::sobel;

src/filter/canny.rs

@@ -0,0 +1,22 @@
+mod double_threshold;
+mod gradient_threshold;
+mod hysteresis;
+
+use double_threshold::*;
+use gradient_threshold::*;
+use hysteresis::*;
+
+use crate::image::*;
+use crate::kernel::Kernel;
+use crate::*;
+
+pub fn canny(img: Image<Luminance>) -> Image<Luminance> {
+    let blurred = kernel::gaussian::<5>(2.0).convolve(&img);
+    let sobel = filter::sobel(blurred);
+    let maxima = gradient_threshold(sobel);
+    let candidates = double_threshold(maxima);
+    let edges = hysteresis(candidates);
+    edges.map(|p| Luminance {
+        y: if p { 1.0 } else { 0.0 },
+    })
+}