Struct Ratio

Source

pub struct Ratio {
    pub numerator: u32,
    pub denominator: u32,
}

Expand description

A rational number (numerator / denominator).

Used to represent frame rates (e.g. 30000/1000 = 30 fps) and frame durations (e.g. 1000/30000 ≈ 0.033 s).

Fields§

§numerator: u32§denominator: u32

Implementations§

Source §

impl Ratio

Source

pub fn as_f64(&self) -> f64

Examples found in repository ?

examples/capture.rs (line 55)

9fn main() {
10    #[cfg(target_os = "macos")]
11    {
12        use camera_stream::platform::macos::device::MacosCameraManager;
13
14        let manager = MacosCameraManager::default();
15
16        // Discover devices
17        let devices: Vec<_> = manager
18            .discover_devices()
19            .expect("failed to discover devices")
20            .collect();
21        println!("Found {} camera(s):", devices.len());
22        for (i, dev) in devices.iter().enumerate() {
23            println!("  [{}] {} (id: {})", i, dev.name(), dev.id());
24        }
25
26        if devices.is_empty() {
27            println!("No cameras found.");
28            return;
29        }
30
31        // Use default device
32        let device = manager
33            .default_device()
34            .expect("failed to get default device")
35            .expect("no default camera");
36
37        println!("\nUsing: {} ({})", device.name(), device.id());
38
39        // Print supported formats
40        let formats: Vec<_> = device
41            .supported_formats()
42            .expect("failed to get formats")
43            .collect();
44        println!("\nSupported formats ({} total):", formats.len());
45        for (i, f) in formats.iter().take(10).enumerate() {
46            println!(
47                "  [{}] {:?} {}x{} ({} frame rate range(s))",
48                i,
49                f.pixel_format,
50                f.size.width,
51                f.size.height,
52                f.frame_rate_ranges().len(),
53            );
54            for rr in f.frame_rate_ranges() {
55                println!("       {:.1}-{:.1} fps", rr.min.as_f64(), rr.max.as_f64(),);
56            }
57        }
58        if formats.len() > 10 {
59            println!("  ... and {} more", formats.len() - 10);
60        }
61
62        // Pick first format or a reasonable default
63        let config = if let Some(f) = formats.first() {
64            let rate =
65                f.frame_rate_ranges()
66                    .first()
67                    .map(|r| r.max)
68                    .unwrap_or(camera_stream::Ratio {
69                        numerator: 30000,
70                        denominator: 1000,
71                    });
72            camera_stream::StreamConfig {
73                pixel_format: f.pixel_format,
74                size: f.size,
75                frame_rate: rate,
76            }
77        } else {
78            println!("No supported formats found.");
79            return;
80        };
81
82        println!(
83            "\nOpening with {:?} {}x{} @ {:.1} fps",
84            config.pixel_format,
85            config.size.width,
86            config.size.height,
87            config.frame_rate.as_f64(),
88        );
89
90        let mut stream = device.open(&config).expect("failed to open stream");
91
92        let frame_count = Arc::new(AtomicU64::new(0));
93        let count_clone = frame_count.clone();
94        let target_frames: u64 = 60;
95
96        stream
97            .start(move |frame| {
98                let n = count_clone.fetch_add(1, Ordering::Relaxed) + 1;
99                let planes = frame.planes();
100                let total_bytes: usize = planes.iter().map(|p| p.data.len()).sum();
101                println!(
102                    "Frame {}: {:?} {}x{} ts={:.3}s planes={} bytes={}",
103                    n,
104                    frame.pixel_format(),
105                    frame.size().width,
106                    frame.size().height,
107                    frame.timestamp().as_secs_f64(),
108                    planes.len(),
109                    total_bytes,
110                );
111            })
112            .expect("failed to start stream");
113
114        // Wait until we've captured enough frames
115        loop {
116            std::thread::sleep(Duration::from_millis(100));
117            if frame_count.load(Ordering::Relaxed) >= target_frames {
118                break;
119            }
120        }
121
122        stream.stop().expect("failed to stop stream");
123        println!(
124            "\nDone. Captured {} frames.",
125            frame_count.load(Ordering::Relaxed)
126        );
127    }
128
129    #[cfg(not(target_os = "macos"))]
130    {
131        println!("This example only works on macOS.");
132    }
133}