Use convolve_sat in canny and sobel

src/filter/canny.rs

@@ -11,7 +11,7 @@ use crate::kernel::Kernel;
 use crate::*;
 
 pub fn canny(img: Image<Luminance>) -> Image<Luminance> {
-    let blurred = kernel::gaussian::<5>(2.0).convolve(&img);
+    let blurred = kernel::gaussian::<5>(1.4).convolve_sat(&img);
     let sobel = filter::sobel(blurred);
     let maxima = gradient_threshold(sobel);
     let candidates = double_threshold(maxima);

src/filter/sobel.rs

@@ -23,8 +23,8 @@ const KERNEL_Y: [[f32; 3]; 3] =
     [[-1.0, -2.0, -1.0], [0.0, 0.0, 0.0], [1.0, 2.0, 1.0]];
 
 pub fn sobel(img: Image<Luminance>) -> Image<Vector> {
-    let x_edges = KERNEL_X.convolve(&img);
-    let y_edges = KERNEL_Y.convolve(&img);
+    let x_edges = KERNEL_X.convolve_sat(&img);
+    let y_edges = KERNEL_Y.convolve_sat(&img);
 
     let mut result = image::Image::<Vector>::with_extent(x_edges.extent);
     result.for_each(|x, y, p| {