Function red_channel

pub fn red_channel<I, C>(image: &I) -> Image<Luma<C>>
where
    I: GenericImage<Pixel = Rgb<C>>,
    Rgb<C>: Pixel<Subpixel = C>,
    C: Primitive,

Creates a grayscale image by extracting the red channel of an RGB image.

Examples

use image::Luma;
use imageproc::map::red_channel;

let image = rgb_image!(
    [1, 2, 3], [2, 4, 6];
    [3, 6, 9], [4, 8, 12]);

let expected = gray_image!(
    1, 2;
    3, 4);

let actual = red_channel(&image);
assert_pixels_eq!(actual, expected);