apple_vision/objectness_saliency/
mod.rs

1#![allow(clippy::cast_possible_wrap, clippy::cast_sign_loss)]
2#![allow(clippy::too_long_first_doc_paragraph)]
3//! `VNGenerateObjectnessBasedSaliencyImageRequest` — discrete object
4//! regions an attention model thinks are salient.
5
6use std::ffi::{CStr, CString};
7use std::path::Path;
8use std::ptr;
9
10use crate::error::VisionError;
11use crate::ffi;
12
13/// One salient object region.
14#[derive(Debug, Clone, Copy, PartialEq)]
15pub struct ObjectnessRegion {
16    pub x: f64,
17    pub y: f64,
18    pub w: f64,
19    pub h: f64,
20    pub confidence: f32,
21}
22
23/// Detect objectness-based salient regions in the image at `path`.
24///
25/// # Errors
26///
27/// Returns [`VisionError`] when the image fails to load or the
28/// Vision request errors.
29pub fn objectness_saliency(path: impl AsRef<Path>) -> Result<Vec<ObjectnessRegion>, VisionError> {
30    let path_str = path.as_ref().to_str().ok_or_else(|| VisionError::InvalidArgument("non-UTF-8 path".into()))?;
31    let cpath = CString::new(path_str).map_err(|e| VisionError::InvalidArgument(format!("path NUL byte: {e}")))?;
32    let mut rects_ptr: *mut ffi::SimpleRectRaw = ptr::null_mut();
33    let mut count: isize = 0;
34    let mut err: *mut std::ffi::c_char = ptr::null_mut();
35    let status = unsafe {
36        ffi::vn_objectness_saliency_in_path(
37            cpath.as_ptr(),
38            &mut rects_ptr,
39            &mut count,
40            &mut err,
41        )
42    };
43    if status != ffi::status::OK {
44        let msg = unsafe { take_err(err) };
45        return Err(VisionError::RequestFailed(msg));
46    }
47    let mut out = Vec::with_capacity(count.max(0) as usize);
48    for i in 0..count {
49        let r = unsafe { rects_ptr.offset(i).read() };
50        out.push(ObjectnessRegion {
51            x: r.x,
52            y: r.y,
53            w: r.w,
54            h: r.h,
55            confidence: r.confidence,
56        });
57    }
58    if !rects_ptr.is_null() {
59        unsafe { ffi::vn_simple_rects_free(rects_ptr, count) };
60    }
61    Ok(out)
62}
63
64unsafe fn take_err(p: *mut std::ffi::c_char) -> String {
65    if p.is_null() {
66        return String::new();
67    }
68    let s = unsafe { CStr::from_ptr(p) }.to_string_lossy().into_owned();
69    unsafe { libc::free(p.cast()) };
70    s
71}
apple_vision/objectness_saliency/mod.rs

apple_vision/objectness_saliency/
mod.rs
