[Example] YOLOv8-ONNXRuntime-Rust example (#6583)

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Glenn Jocher <glenn.jocher@ultralytics.com>

examples/YOLOv8-ONNXRuntime-Rust/src/lib.rs

@@ -0,0 +1,119 @@
+#![allow(clippy::type_complexity)]
+
+use std::io::{Read, Write};
+
+pub mod cli;
+pub mod model;
+pub mod ort_backend;
+pub mod yolo_result;
+pub use crate::cli::Args;
+pub use crate::model::YOLOv8;
+pub use crate::ort_backend::{Batch, OrtBackend, OrtConfig, OrtEP, YOLOTask};
+pub use crate::yolo_result::{Bbox, Embedding, Point2, YOLOResult};
+
+pub fn non_max_suppression(
+    xs: &mut Vec<(Bbox, Option<Vec<Point2>>, Option<Vec<f32>>)>,
+    iou_threshold: f32,
+) {
+    xs.sort_by(|b1, b2| b2.0.confidence().partial_cmp(&b1.0.confidence()).unwrap());
+
+    let mut current_index = 0;
+    for index in 0..xs.len() {
+        let mut drop = false;
+        for prev_index in 0..current_index {
+            let iou = xs[prev_index].0.iou(&xs[index].0);
+            if iou > iou_threshold {
+                drop = true;
+                break;
+            }
+        }
+        if !drop {
+            xs.swap(current_index, index);
+            current_index += 1;
+        }
+    }
+    xs.truncate(current_index);
+}
+
+pub fn gen_time_string(delimiter: &str) -> String {
+    let offset = chrono::FixedOffset::east_opt(8 * 60 * 60).unwrap(); // Beijing
+    let t_now = chrono::Utc::now().with_timezone(&offset);
+    let fmt = format!(
+        "%Y{}%m{}%d{}%H{}%M{}%S{}%f",
+        delimiter, delimiter, delimiter, delimiter, delimiter, delimiter
+    );
+    t_now.format(&fmt).to_string()
+}
+
+pub const SKELETON: [(usize, usize); 16] = [
+    (0, 1),
+    (0, 2),
+    (1, 3),
+    (2, 4),
+    (5, 6),
+    (5, 11),
+    (6, 12),
+    (11, 12),
+    (5, 7),
+    (6, 8),
+    (7, 9),
+    (8, 10),
+    (11, 13),
+    (12, 14),
+    (13, 15),
+    (14, 16),
+];
+
+pub fn check_font(font: &str) -> rusttype::Font<'static> {
+    // check then load font
+
+    // ultralytics font path
+    let font_path_config = match dirs::config_dir() {
+        Some(mut d) => {
+            d.push("Ultralytics");
+            d.push(font);
+            d
+        }
+        None => panic!("Unsupported operating system. Now support Linux, MacOS, Windows."),
+    };
+
+    // current font path
+    let font_path_current = std::path::PathBuf::from(font);
+
+    // check font
+    let font_path = if font_path_config.exists() {
+        font_path_config
+    } else if font_path_current.exists() {
+        font_path_current
+    } else {
+        println!("Downloading font...");
+        let source_url = "https://ultralytics.com/assets/Arial.ttf";
+        let resp = ureq::get(source_url)
+            .timeout(std::time::Duration::from_secs(500))
+            .call()
+            .unwrap_or_else(|err| panic!("> Failed to download font: {source_url}: {err:?}"));
+
+        // read to buffer
+        let mut buffer = vec![];
+        let total_size = resp
+            .header("Content-Length")
+            .and_then(|s| s.parse::<u64>().ok())
+            .unwrap();
+        let _reader = resp
+            .into_reader()
+            .take(total_size)
+            .read_to_end(&mut buffer)
+            .unwrap();
+
+        // save
+        let _path = std::fs::File::create(font).unwrap();
+        let mut writer = std::io::BufWriter::new(_path);
+        writer.write_all(&buffer).unwrap();
+        println!("Font saved at: {:?}", font_path_current.display());
+        font_path_current
+    };
+
+    // load font
+    let buffer = std::fs::read(font_path).unwrap();
+    rusttype::Font::try_from_vec(buffer).unwrap()
+}