Function set_control

rustcv-camera/src/backend/linux/sys.rs:241–249

Set a V4L2 control value (VIDIOC_S_CTRL). 设置 V4L2 控制参数值（VIDIOC_S_CTRL）。 Common uses: - Disable `exposure_dynamic_framerate` (id=0x009a0903, value=0) to prevent the camera from reducing FPS in low light. 常见用途： - 禁用 `exposure_dynamic_framerate`（id=0x009a0903, value=0）， 防止摄像头在低光照下自动降低帧率。

(fd: RawFd, id: u32, value: i32)

/// - 禁用 `exposure_dynamic_framerate`（id=0x009a0903, value=0），
///   防止摄像头在低光照下自动降低帧率。
pub fn set_control(fd: RawFd, id: u32, value: i32) -> io::Result<()> {
    let mut ctrl: v4l2_control = unsafe { std::mem::zeroed() };
    ctrl.id = id;
    ctrl.value = value;
    unsafe {
        v4l2_ioctl(fd, VIDIOC_S_CTRL, &mut ctrl as *mut _ as *mut libc::c_void)?;
    }
    Ok(())
}

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