// [How to use]
// check USB camera is available.
string[] devices = UsbCamera.FindDevices();
if (devices.Length == 0) return; // no camera.
            
// check format.
int cameraIndex = 0;
UsbCamera.VideoFormat[] formats = UsbCamera.GetVideoFormat(cameraIndex);
for(int i=0; i<formats.Length; i++) Console.WriteLine("{0}:{1}", i, formats[i]);
            
// create usb camera and start.
var camera = new UsbCamera(cameraIndex, formats[0]);
camera.Start();
            
// get image.
// Immediately after starting the USB camera,
// GetBitmap() fails because image buffer is not prepared yet.
var bmp = camera.GetBitmap();
            
// show image in PictureBox.
var timer = new System.Timers.Timer(100) { SynchronizingObject = this };
timer.Elapsed += (s, ev) => pbxScreen.Image = camera.GetBitmap();
timer.Start();

// release resource when close.
this.FormClosing += (s, ev) => timer.Stop();
this.FormClosing += (s, ev) => camera.Stop();

// adjust properties.
UsbCamera.PropertyItems.Property prop;
prop = camera.Properties[DirectShow.CameraControlProperty.Exposure];
if (prop.Available)
{
    var min = prop.Min;
    var max = prop.Max;
    var def = prop.Default;
    var step = prop.Step;
    prop.SetValue(DirectShow.CameraControlFlags.Manual, prop.Default);
}

prop = camera.Properties[DirectShow.VideoProcAmpProperty.WhiteBalance];
if (prop.Available && prop.CanAuto)
{
    prop.SetValue(DirectShow.CameraControlFlags.Auto, 0);
}