fn hysteresis(
    input: &ImageBuffer<Luma<f32>, Vec<f32>>,
    low_thresh: f32,
    high_thresh: f32,
) -> ImageBuffer<Luma<u8>, Vec<u8>> {
    let max_brightness = Luma::white();
    let min_brightness = Luma::black();
    // Init output image as all black.
    let mut out = ImageBuffer::from_pixel(input.width(), input.height(), min_brightness);
    // Stack. Possible optimization: Use previously allocated memory, i.e. gx.
    let mut edges = Vec::with_capacity(((input.width() * input.height()) / 2) as usize);
    for y in 1..input.height() - 1 {
        for x in 1..input.width() - 1 {
            let inp_pix = *input.get_pixel(x, y);
            let out_pix = *out.get_pixel(x, y);
            // If the edge strength is higher than high_thresh, mark it as an edge.
            if inp_pix[0] >= high_thresh && out_pix[0] == 0 {
                out.put_pixel(x, y, max_brightness);
                edges.push((x, y));
                // Track neighbors until no neighbor is >= low_thresh.
                while !edges.is_empty() {
                    let (nx, ny) = edges.pop().unwrap();
                    let neighbor_indices = [
                        (nx + 1, ny),
                        (nx + 1, ny + 1),
                        (nx, ny + 1),
                        (nx - 1, ny - 1),
                        (nx - 1, ny),
                        (nx - 1, ny + 1),
                    ];

                    for neighbor_idx in &neighbor_indices {
                        let in_neighbor = *input.get_pixel(neighbor_idx.0, neighbor_idx.1);
                        let out_neighbor = *out.get_pixel(neighbor_idx.0, neighbor_idx.1);
                        if in_neighbor[0] >= low_thresh && out_neighbor[0] == 0 {
                            out.put_pixel(neighbor_idx.0, neighbor_idx.1, max_brightness);
                            edges.push((neighbor_idx.0, neighbor_idx.1));
                        }
                    }
                }
            }
        }
    }
    out
}
/// Filter out edges with the thresholds.
/// Non-recursive breadth-first search.
Filter out edges with the thresholds.
Non-recursive breadth-first search.
Filter out edges with the thresholds . Non - recursive breadth - first search .
fn hysteresis(
    input: &ImageBuffer<Luma<f32>, Vec<f32>>,
    low_thresh: f32,
    high_thresh: f32,
) -> ImageBuffer<Luma<u8>, Vec<u8>> {
    let max_brightness = Luma::white();
    let min_brightness = Luma::black();
    // Init output image as all black.
    let mut out = ImageBuffer::from_pixel(input.width(), input.height(), min_brightness);
    // Stack. Possible optimization: Use previously allocated memory, i.e. gx.
    let mut edges = Vec::with_capacity(((input.width() * input.height()) / 2) as usize);
    for y in 1..input.height() - 1 {
        for x in 1..input.width() - 1 {
            let inp_pix = *input.get_pixel(x, y);
            let out_pix = *out.get_pixel(x, y);
            // If the edge strength is higher than high_thresh, mark it as an edge.
            if inp_pix[0] >= high_thresh && out_pix[0] == 0 {
                out.put_pixel(x, y, max_brightness);
                edges.push((x, y));
                // Track neighbors until no neighbor is >= low_thresh.
                while !edges.is_empty() {
                    let (nx, ny) = edges.pop().unwrap();
                    let neighbor_indices = [
                        (nx + 1, ny),
                        (nx + 1, ny + 1),
                        (nx, ny + 1),
                        (nx - 1, ny - 1),
                        (nx - 1, ny),
                        (nx - 1, ny + 1),
                    ];
                    for neighbor_idx in &neighbor_indices {
                        let in_neighbor = *input.get_pixel(neighbor_idx.0, neighbor_idx.1);
                        let out_neighbor = *out.get_pixel(neighbor_idx.0, neighbor_idx.1);
                        if in_neighbor[0] >= low_thresh && out_neighbor[0] == 0 {
                            out.put_pixel(neighbor_idx.0, neighbor_idx.1, max_brightness);
                            edges.push((neighbor_idx.0, neighbor_idx.1));
                        }
                    }
                }
            }
        }
    }
    out
}
fn hysteresis ( input : & ImageBuffer < Luma < f32 > , Vec < f32 > > , low_thresh : f32 , high_thresh : f32 , ) -> ImageBuffer < Luma < u8 > , Vec < u8 > > { let max_brightness = Luma :: white ( ) ; let min_brightness = Luma :: black ( ) ; // Init output image as all black. let mut out = ImageBuffer :: from_pixel ( input . width ( ) , input . height ( ) , min_brightness ) ; // Stack. Possible optimization: Use previously allocated memory, i.e. gx. let mut edges = Vec :: with_capacity ( ( ( input . width ( ) * input . height ( ) ) / 2 ) as usize ) ; for y in 1 .. input . height ( ) - 1 { for x in 1 .. input . width ( ) - 1 { let inp_pix = * input . get_pixel ( x , y ) ; let out_pix = * out . get_pixel ( x , y ) ; // If the edge strength is higher than high_thresh, mark it as an edge. if inp_pix [ 0 ] >= high_thresh && out_pix [ 0 ] == 0 { out . put_pixel ( x , y , max_brightness ) ; edges . push ( ( x , y ) ) ; // Track neighbors until no neighbor is >= low_thresh. while ! edges . is_empty ( ) { let ( nx , ny ) = edges . pop ( ) . unwrap ( ) ; let neighbor_indices = [ ( nx + 1 , ny ) , ( nx + 1 , ny + 1 ) , ( nx , ny + 1 ) , ( nx - 1 , ny - 1 ) , ( nx - 1 , ny ) , ( nx - 1 , ny + 1 ) , ] ; for neighbor_idx in & neighbor_indices { let in_neighbor = * input . get_pixel ( neighbor_idx . 0 , neighbor_idx . 1 ) ; let out_neighbor = * out . get_pixel ( neighbor_idx . 0 , neighbor_idx . 1 ) ; if in_neighbor [ 0 ] >= low_thresh && out_neighbor [ 0 ] == 0 { out . put_pixel ( neighbor_idx . 0 , neighbor_idx . 1 , max_brightness ) ; edges . push ( ( neighbor_idx . 0 , neighbor_idx . 1 ) ) ; } } } } } } out }
Filter out edges with the thresholds.
Filter out edges with the thresholds .
input
&ImageBuffer<Luma<f32>, Vec<f32>>
low_thresh
f32
high_thresh
f32
input
&ImageBuffer<Luma<f32>, Vec<f32>>
low_thresh
f32
high_thresh
f32