/// <summary>
/// Детектирование лиц и прорисовка квадрата на каждом из лиц.
/// </summary>
private void DetectFaces()
{
// Проверка на получения картинки
if (null != cameraBitmap)
{
//Получаем ширину
var width = cameraBitmap.Width;
//Получаем высоту
var height = cameraBitmap.Height;
//Создаем экземпляр класса нативных библиотек распознования от Android
var detector = new FaceDetector(width, height, MaxFaces);
//Создаем массив лиц
var faces = new FaceDetector.Face[MaxFaces];
//Создаем основной Bitmap
var bitmap565 = Bitmap.CreateBitmap(width, height, Bitmap.Config.Rgb565);
var ditherPaint = new Paint();
//Рамка захвата
var drawPaint = new Paint();
ditherPaint.Dither = true;
//Устанавливаем цвет квадрата, штриховку, толщину
drawPaint.Color = Color.Blue;
drawPaint.SetStyle(Paint.Style.Stroke);
drawPaint.StrokeWidth = 2;
//Создаем холст и устанавливаем
var canvas = new Canvas();
canvas.SetBitmap(bitmap565);
canvas.DrawBitmap(cameraBitmap, 0, 0, ditherPaint);
//Получаем количество лиц
var facesFound = detector.FindFaces(bitmap565, faces);
//Средняя точка
var midPoint = new PointF();
//Расстояние до глаз
float eyeDistance;
float confidence;
//Печать в консоль для тестирования приложения
Console.WriteLine($"Найдено лиц: {facesFound}");
//Проверка, что найдено хоть одно лицо
if (facesFound > 0)
{
for (var index = 0; index < facesFound; ++index)
{
faces[index].GetMidPoint(midPoint);
eyeDistance = faces[index].EyesDistance();
confidence = faces[index].Confidence();
//Печатаем для отладки в консоль
Console.WriteLine($"Коэфициент доверия: {confidence} Расстояние до глаз: {eyeDistance}" +
$"Средняя точка: ( X: {midPoint.X} Y: {midPoint.Y} )");
//Передаем в TextView значение расстояния до лица
((TextView)FindViewById(Resource.Id.tvDistanceToCamera)).Text = $"{eyeDistance:0.00} см";
//Рисуем квадрат
canvas.DrawRect((int)midPoint.X - eyeDistance,
(int)midPoint.Y - eyeDistance,
(int)midPoint.X + eyeDistance,
(int)midPoint.Y + eyeDistance, drawPaint);
}
}
var imageView = (ImageView)FindViewById(Resource.Id.image_view);
imageView.SetImageBitmap(bitmap565);
}
}
/// <summary>
/// detect faces on a picture and draw a square in each face
/// </summary>
private void detectFaces()
{
//first check if picture has been taken
if (null != cameraBitmap)
{
//get width of a picture
int width = cameraBitmap.Width;
//get height of a picture
int height = cameraBitmap.Height;
//Initialize a facedetector with the picture dimensions and the max number of faces to check
FaceDetector detector = new FaceDetector(width, height, MainActivity.MAX_FACES);
//Create an array of faces with the number of max faces to check
Android.Media.FaceDetector.Face[] faces = new Android.Media.FaceDetector.Face[MainActivity.MAX_FACES];
//create a main bitmap
Bitmap bitmap565 = Bitmap.CreateBitmap(width, height, Bitmap.Config.Rgb565);
//create a dither paint
Paint ditherPaint = new Paint();
//create a draw paint
Paint drawPaint = new Paint();
//set true dither to dither paint variable
ditherPaint.Dither = true;
//set color red for the square
drawPaint.Color = Color.Red;
//set stroke to style
drawPaint.SetStyle(Paint.Style.Stroke);
//set stroke width
drawPaint.StrokeWidth = 2;
//Create a canvas
Canvas canvas = new Canvas();
//set bitmap to canvas
canvas.SetBitmap(bitmap565);
//draw bitmap to canvas
canvas.DrawBitmap(cameraBitmap, 0, 0, ditherPaint);
//get a number of faces detected
int facesFound = detector.FindFaces(bitmap565, faces);
//mid face point
PointF midPoint = new PointF();
//eye distance variable
float eyeDistance = 0.0f;
//confidence variable
float confidence = 0.0f;
//print numbre of faces found
System.Console.WriteLine("Number of faces found: " + facesFound);
//check if found at least one face
if (facesFound > 0)
{
//for each face draw a red squeare
for (int index = 0; index < facesFound; ++index)
{
// get midpoint of a face
faces[index].GetMidPoint(midPoint);
//get eye distance
eyeDistance = faces[index].EyesDistance();
//get confidence
confidence = faces [index].Confidence();
//print all parameters
System.Console.WriteLine("Confidence: " + confidence +
", Eye distance: " + eyeDistance +
", Mid Point: (" + midPoint.X + ", " + midPoint.Y + ")");
//draw a square in the picture
canvas.DrawRect((int)midPoint.X - eyeDistance,
(int)midPoint.Y - eyeDistance,
(int)midPoint.X + eyeDistance,
(int)midPoint.Y + eyeDistance, drawPaint);
}
}
//get imageview from layout
ImageView imageView = (ImageView)FindViewById(Resource.Id.image_view);
//set image with the red squares to imageview
imageView.SetImageBitmap(bitmap565);
}
}
public void Run()
{
EmCropImage eci = this.ECI;
if (eci == null)
{
return;
}
this.MImageMatrix = eci.ImageView.ImageMatrix;
Bitmap faceBitmap = PrepareBitmap();
if (faceBitmap != null)
{
this.Scale = 1.0F / this.Scale;
if (faceBitmap != null && eci.DoingFaceDetection)
{
FaceDetector detector = new FaceDetector(faceBitmap.Width,
faceBitmap.Height, this.Faces.Length);
this.NumberOfFaces = detector.FindFaces(faceBitmap, this.Faces);
}
if (faceBitmap != null && faceBitmap != eci.Bitmap)
{
faceBitmap.Recycle();
}
}
eci.MHandler.Post(() => {
eci.WaitingToPick = this.NumberOfFaces > 1;
if (this.NumberOfFaces > 0)
{
for (int i = 0; i < this.NumberOfFaces; i++)
{
HandleFace(this.Faces[i]);
}
}
else
{
MakeDefault();
}
eci.ImageView.Invalidate();
if (eci.ImageView.MotionHighlightViews.Count == 1)
{
eci.MCrop = eci.ImageView.MotionHighlightViews [0];
eci.MCrop.Focused = true;
}
// Translation Note: I have no idea how to get to this area of code.
// It has something to do with face recognition.
if (this.NumberOfFaces > 1)
{
Toast t = Toast.MakeText(eci,
"Touch a face to begin.",
ToastLength.Short);
t.Show();
}
});
}