Image: How can I draw a rectangle in image

[hasanOryx]

I'm trying to open an image, converting it into gray, and drawing a rectangle, then save it under another name, so, I'm using image and imageproc, and wrote the below code:

use image::{GenericImageView, FilterType, Rgb};
use imageproc::drawing::draw_hollow_rect_mut;
use imageproc::rect::Rect;

fn main() {
    let img = image::open("self.jpg").unwrap();

    let mut gray = img.grayscale();
    let white = Rgb([255u8, 255u8, 255u8]);

    draw_hollow_rect_mut(&mut gray, Rect::at(60, 10).of_size(20, 20), white);

    gray.save("gray.png").unwrap();
}

But I got the below error:

error[E0277]: the trait bound `image::dynimage::DynamicImage: image::image::GenericImage` is not satisfied
  --> src/main.rs:34:5
   |
34 |     draw_hollow_rect_mut(&mut gray, Rect::at(60, 10).of_size(20, 20), white);
   |     ^^^^^^^^^^^^^^^^^^^^ the trait `image::image::GenericImage` is not implemented for `image::dynimage::DynamicImage`

   = note: required by `imageproc::drawing::rect::draw_hollow_rect_mut`

[fintelia]

Seems to be a version issue: imageproc:0.18.0 pulls in image:0.21.3, whereas the latest version of image is 0.22.1. You can fix this by putting compatible versions in your Cargo.toml:

[dependencies]
image = "0.21.3"
imageproc = "0.18.0"

(The way you can figure out this sort of thing is to see that the docs say DynamicImage does implement GenericImage, suggesting a version mismatch, and then use cargo-tree to figure out exactly what the mismatch is.)

@HeroicKatora we should probably figure out a way to make sure that the latest versions of image and imageproc remain compatible so people don't keep running into this.

[theotherphil]

I've just published imageproc 0.19, which references image 0.22.1