Method resolve_device_id

rustcv/src/videoio/mod.rs:305–334

(driver: &dyn Driver, index: u32)

    }

    // 内部辅助：解决设备 ID 的平台差异
    #[allow(unused_variables)]
    fn resolve_device_id(driver: &dyn Driver, index: u32) -> Result<String> {
        #[cfg(target_os = "linux")]
        {
            // Linux 策略：直接映射 ID，模仿 OpenCV
            // index 0 -> "/dev/video0"
            // index 1 -> "/dev/video1"
            Ok(format!("/dev/video{}", index))
        }

        #[cfg(not(target_os = "linux"))]
        {
            // macOS/Windows 策略：列表排序后取索引
            let mut devices = driver
                .list_devices()
                .map_err(|e| anyhow!("Failed to list devices: {}", e))?;

            // 关键：必须排序，确保 new(0) 永远打开同一个设备
            devices.sort_by(|a, b| a.id.cmp(&b.id));

            let info = devices.get(index as usize).ok_or_else(|| {
                anyhow!(
                    "Camera index {} out of range. Found {} devices.",
                    index,
                    devices.len()
                )
            })?;

            Ok(info.id.clone())
        }
    }
}