Android原生人脸识别Camera2+FaceDetector 快速实现人脸跟踪

title: Android原生人脸识别Camera2+FaceDetector 快速实现人脸跟踪

categories:

Android

tags:人脸识别FaceDetectorCamera2

date: -05-27 14:02:13

前言本人博客

本篇主要介绍Android原生Api人脸检测FaceDetector的使用，该方法检测人脸可以

做到的是，检测到屏幕有无人脸，有多少个人脸，人脸的双眼眉心位置2d坐标，双眼间距，

但是本人测到该方法的坑，检测有无人脸确实好用，但是如果要精确的测量人脸位置，距离等，会有偏差，毕竟是2d坐标，对现实

定位不准确，我感觉可以这样理解，

然后大家如果要实现该功能的时候，如果这些不够用，就不用考虑该方法了。

废话不多说，实现开始，

实现

1.首先可以实现一个自定义view用来在屏幕上画方框

class FaceView : View {lateinit var mPaint: Paintprivate var mCorlor = "#42ed45"private var mFaces: ArrayList<RectF>? = nullconstructor(context: Context) : super(context) {init()}constructor(context: Context, attrs: AttributeSet?) : super(context, attrs) {init()}constructor(context: Context, attrs: AttributeSet?, defStyleAttr: Int) : super(context, attrs, defStyleAttr) {init()}private fun init() {mPaint = Paint()mPaint.color = Color.parseColor(mCorlor)mPaint.style = Paint.Style.STROKEmPaint.strokeWidth = TypedValue.applyDimension(PLEX_UNIT_DIP, 3f, context.resources.displayMetrics)mPaint.isAntiAlias = true}override fun onDraw(canvas: Canvas) {super.onDraw(canvas)mFaces?.let {for (face in it) {canvas.drawRect(face, mPaint)}}}fun setFaces(faces: ArrayList<RectF>) {this.mFaces = facesinvalidate()}}

imageUtil用来处理返回的基础格式

/*** Author: Sar_Wang* Date: /5/11 3:40 PM* Description:*/public class ImageUtil {/*** 将Y:U:V == 4:2:2的数据转换为nv21** @param yY 数据* @param uU 数据* @param vV 数据* @param nv21 生成的nv21，需要预先分配内存* @param stride 步长* @param height 图像高度*/public static void yuv422ToYuv420sp(byte[] y, byte[] u, byte[] v, byte[] nv21, int stride, int height) {System.arraycopy(y, 0, nv21, 0, y.length);// 注意，若length值为 y.length * 3 / 2 会有数组越界的风险，需使用真实数据长度计算int length = y.length + u.length / 2 + v.length / 2;int uIndex = 0, vIndex = 0;for (int i = stride * height; i < length; i += 2) {nv21[i] = v[vIndex];nv21[i + 1] = u[uIndex];vIndex += 2;uIndex += 2;}}/*** 将Y:U:V == 4:1:1的数据转换为nv21** @param yY 数据* @param uU 数据* @param vV 数据* @param nv21 生成的nv21，需要预先分配内存* @param stride 步长* @param height 图像高度*/public static void yuv420ToYuv420sp(byte[] y, byte[] u, byte[] v, byte[] nv21, int stride, int height) {System.arraycopy(y, 0, nv21, 0, y.length);// 注意，若length值为 y.length * 3 / 2 会有数组越界的风险，需使用真实数据长度计算int length = y.length + u.length + v.length;int uIndex = 0, vIndex = 0;for (int i = stride * height; i < length; i++) {nv21[i] = v[vIndex++];nv21[i + 1] = u[uIndex++];}}}

然后是调用相机的activity的布局

<?xml version="1.0" encoding="utf-8"?><FrameLayout xmlns:android="/apk/res/android"xmlns:app="/apk/res-auto"xmlns:tools="/tools"android:layout_width="match_parent"android:layout_height="match_parent"><TextureViewandroid:id="@+id/textureView"android:layout_width="match_parent"android:layout_height="match_parent"/><TextViewandroid:id="@+id/switch_Camera"android:layout_gravity="end|bottom"android:layout_marginBottom="90dp"android:layout_marginEnd="40dp"android:text="切换摄像头"android:layout_width="wrap_content"android:layout_height="wrap_content" /><com.sto.itgspeaker.FaceViewandroid:id="@+id/faceView"android:layout_width="match_parent"android:layout_height="match_parent"/></FrameLayout>

然后这里剩的麻烦，用了一个大神写的相机辅助类，感兴趣的可以看一下源码

public class Camera2Helper {private static final String TAG = "Camera2Helper";private Point maxPreviewSize;private Point minPreviewSize;public static final String CAMERA_ID_FRONT = "1";public static final String CAMERA_ID_BACK = "0";private String mCameraId;private String specificCameraId;private Camera2Listener camera2Listener;private TextureView mTextureView;private int rotation;private Point previewViewSize;private Point specificPreviewSize;private boolean isMirror;private Context context;private boolean mCalibrated;private boolean mIsVertical = true;/*** A {@link CameraCaptureSession } for camera preview.*/private CameraCaptureSession mCaptureSession;/*** A reference to the opened {@link CameraDevice}.*/private CameraDevice mCameraDevice;private Size mPreviewSize;private Camera2Helper(Camera2Helper.Builder builder) {mTextureView = builder.previewDisplayView;specificCameraId = builder.specificCameraId;camera2Listener = builder.camera2Listener;rotation = builder.rotation;previewViewSize = builder.previewViewSize;specificPreviewSize = builder.previewSize;maxPreviewSize = builder.maxPreviewSize;minPreviewSize = builder.minPreviewSize;isMirror = builder.isMirror;context = builder.context;if (isMirror) {mTextureView.setScaleX(-1);}}public void setConfiguration(boolean val) {mIsVertical = val;}public void switchCamera() {if (CAMERA_ID_BACK.equals(mCameraId)) {specificCameraId = CAMERA_ID_FRONT;} else if (CAMERA_ID_FRONT.equals(mCameraId)) {specificCameraId = CAMERA_ID_BACK;}stop();start();}private int getCameraOri(int rotation, String cameraId) {int degrees = rotation * 90;switch (rotation) {case Surface.ROTATION_0:degrees = 0;break;case Surface.ROTATION_90:degrees = 90;break;case Surface.ROTATION_180:degrees = 180;break;case Surface.ROTATION_270:degrees = 270;break;default:break;}int result;if (CAMERA_ID_FRONT.equals(cameraId)) {result = (mSensorOrientation + degrees) % 360;result = (360 - result) % 360;} else {result = (mSensorOrientation - degrees + 360) % 360;}Log.i(TAG, "getCameraOri: " + rotation + " " + result + " " + mSensorOrientation);return result;}private final TextureView.SurfaceTextureListener mSurfaceTextureListener= new TextureView.SurfaceTextureListener() {@Overridepublic void onSurfaceTextureAvailable(SurfaceTexture texture, int width, int height) {Log.i(TAG, "onSurfaceTextureAvailable: ");openCamera();}@Overridepublic void onSurfaceTextureSizeChanged(SurfaceTexture texture, int width, int height) {Log.i(TAG, "onSurfaceTextureSizeChanged: ");configureTransform(width, height);}@Overridepublic boolean onSurfaceTextureDestroyed(SurfaceTexture texture) {Log.i(TAG, "onSurfaceTextureDestroyed: ");return true;}@Overridepublic void onSurfaceTextureUpdated(SurfaceTexture texture) {}};private CameraDevice.StateCallback mDeviceStateCallback = new CameraDevice.StateCallback() {@Overridepublic void onOpened(@NonNull CameraDevice cameraDevice) {Log.i(TAG, "onOpened: ");// This method is called when the camera is opened. We start camera preview here.mCameraOpenCloseLock.release();mCameraDevice = cameraDevice;createCameraPreviewSession();if (camera2Listener != null) {camera2Listener.onCameraOpened(cameraDevice, mCameraId, mPreviewSize, getCameraOri(rotation, mCameraId), isMirror);}}@Overridepublic void onDisconnected(@NonNull CameraDevice cameraDevice) {Log.i(TAG, "onDisconnected: ");mCameraOpenCloseLock.release();cameraDevice.close();mCameraDevice = null;if (camera2Listener != null) {camera2Listener.onCameraClosed();}}@Overridepublic void onError(@NonNull CameraDevice cameraDevice, int error) {Log.i(TAG, "onError: ");mCameraOpenCloseLock.release();cameraDevice.close();mCameraDevice = null;if (camera2Listener != null) {camera2Listener.onCameraError(new Exception("error occurred, code is " + error));}}};private CameraCaptureSession.StateCallback mCaptureStateCallback = new CameraCaptureSession.StateCallback() {@Overridepublic void onConfigured(@NonNull CameraCaptureSession cameraCaptureSession) {Log.i(TAG, "onConfigured: ");// The camera is already closedif (null == mCameraDevice) {return;}// When the session is ready, we start displaying the preview.mCaptureSession = cameraCaptureSession;try {mCaptureSession.setRepeatingRequest(mPreviewRequestBuilder.build(),mCaptureCallBack, mBackgroundHandler);} catch (CameraAccessException e) {e.printStackTrace();}}@Overridepublic void onConfigureFailed(@NonNull CameraCaptureSession cameraCaptureSession) {Log.i(TAG, "onConfigureFailed: ");if (camera2Listener != null) {camera2Listener.onCameraError(new Exception("configureFailed"));}}};private CameraCaptureSession.CaptureCallback mCaptureCallBack = new CameraCaptureSession.CaptureCallback(){@Overridepublic void onCaptureCompleted(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, @NonNull TotalCaptureResult result) {super.onCaptureCompleted(session, request, result);camera2Listener.onHandleFaces(result);}@Overridepublic void onCaptureFailed(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, @NonNull CaptureFailure failure) {super.onCaptureFailed(session, request, failure);}};/*** An additional thread for running tasks that shouldn't block the UI.*/private HandlerThread mBackgroundThread;/*** A {@link Handler} for running tasks in the background.*/private Handler mBackgroundHandler;private ImageReader mImageReader;/*** {@link CaptureRequest.Builder} for the camera preview*/private CaptureRequest.Builder mPreviewRequestBuilder;/*** A {@link Semaphore} to prevent the app from exiting before closing the camera.*/private Semaphore mCameraOpenCloseLock = new Semaphore(1);/*** Orientation of the camera sensor*/private int mSensorOrientation;private Size getBestSupportedSize(List<Size> sizes) {Size defaultSize = sizes.get(0);Size[] tempSizes = sizes.toArray(new Size[0]);Arrays.sort(tempSizes, new Comparator<Size>() {@Overridepublic int compare(Size o1, Size o2) {if (o1.getWidth() > o2.getWidth()) {return -1;} else if (o1.getWidth() == o2.getWidth()) {return o1.getHeight() > o2.getHeight() ? -1 : 1;} else {return 1;}}});sizes = new ArrayList<>(Arrays.asList(tempSizes));for (int i = sizes.size() - 1; i >= 0; i--) {if (maxPreviewSize != null) {if (sizes.get(i).getWidth() > maxPreviewSize.x || sizes.get(i).getHeight() > maxPreviewSize.y) {sizes.remove(i);continue;}}if (minPreviewSize != null) {if (sizes.get(i).getWidth() < minPreviewSize.x || sizes.get(i).getHeight() < minPreviewSize.y) {sizes.remove(i);}}}if (sizes.size() == 0) {String msg = "can not find suitable previewSize, now using default";if (camera2Listener != null) {Log.e(TAG, msg);camera2Listener.onCameraError(new Exception(msg));}return defaultSize;}Size bestSize = sizes.get(0);float previewViewRatio;if (previewViewSize != null) {previewViewRatio = (float) previewViewSize.x / (float) previewViewSize.y;} else {previewViewRatio = (float) bestSize.getWidth() / (float) bestSize.getHeight();}if (previewViewRatio > 1) {previewViewRatio = 1 / previewViewRatio;}for (Size s : sizes) {if (specificPreviewSize != null && specificPreviewSize.x == s.getWidth() && specificPreviewSize.y == s.getHeight()) {return s;}if (Math.abs((s.getHeight() / (float) s.getWidth()) - previewViewRatio) < Math.abs(bestSize.getHeight() / (float) bestSize.getWidth() - previewViewRatio)) {bestSize = s;}}return bestSize;}public synchronized void start() {if (mCameraDevice != null) {return;}startBackgroundThread();// When the screen is turned off and turned back on, the SurfaceTexture is already// available, and "onSurfaceTextureAvailable" will not be called. In that case, we can open// a camera and start preview from here (otherwise, we wait until the surface is ready in// the SurfaceTextureListener).if (mTextureView.isAvailable()) {openCamera();} else {mTextureView.setSurfaceTextureListener(mSurfaceTextureListener);}}public synchronized void stop() {if (mCameraDevice == null) {return;}closeCamera();stopBackgroundThread();}public void release() {stop();mTextureView = null;camera2Listener = null;context = null;}private void setUpCameraOutputs(CameraManager cameraManager) {try {if (configCameraParams(cameraManager, specificCameraId)) {return;}for (String cameraId : cameraManager.getCameraIdList()) {if (configCameraParams(cameraManager, cameraId)) {return;}}} catch (CameraAccessException e) {e.printStackTrace();} catch (NullPointerException e) {// Currently an NPE is thrown when the Camera2API is used but not supported on the// device this code runs.if (camera2Listener != null) {camera2Listener.onCameraError(e);}}}private boolean configCameraParams(CameraManager manager, String cameraId) throws CameraAccessException {CameraCharacteristics characteristics= manager.getCameraCharacteristics(cameraId);StreamConfigurationMap map = characteristics.get(CameraCharacteristics.SCALER_STREAM_CONFIGURATION_MAP);if (map == null) {return false;}mPreviewSize = getBestSupportedSize(new ArrayList<Size>(Arrays.asList(map.getOutputSizes(SurfaceTexture.class))));mImageReader = ImageReader.newInstance(mPreviewSize.getWidth(), mPreviewSize.getHeight(),ImageFormat.YUV_420_888, 2);mImageReader.setOnImageAvailableListener(new OnImageAvailableListenerImpl(), mBackgroundHandler);mSensorOrientation = characteristics.get(CameraCharacteristics.SENSOR_ORIENTATION);mCameraId = cameraId;return true;}private void openCamera() {CameraManager cameraManager = (CameraManager) context.getSystemService(Context.CAMERA_SERVICE);setUpCameraOutputs(cameraManager);configureTransform(mTextureView.getWidth(), mTextureView.getHeight());try {if (!mCameraOpenCloseLock.tryAcquire(2500, TimeUnit.MILLISECONDS)) {throw new RuntimeException("Time out waiting to lock camera opening.");}cameraManager.openCamera(mCameraId, mDeviceStateCallback, mBackgroundHandler);} catch (CameraAccessException e) {if (camera2Listener != null) {camera2Listener.onCameraError(e);}} catch (InterruptedException e) {if (camera2Listener != null) {camera2Listener.onCameraError(e);}}}/*** Closes the current {@link CameraDevice}.*/private void closeCamera() {try {mCameraOpenCloseLock.acquire();if (null != mCaptureSession) {mCaptureSession.close();mCaptureSession = null;}if (null != mCameraDevice) {mCameraDevice.close();mCameraDevice = null;}if (null != mImageReader) {mImageReader.close();mImageReader = null;}if (camera2Listener != null) {camera2Listener.onCameraClosed();}} catch (InterruptedException e) {if (camera2Listener != null) {camera2Listener.onCameraError(e);}} finally {mCameraOpenCloseLock.release();}}/*** Starts a background thread and its {@link Handler}.*/private void startBackgroundThread() {mBackgroundThread = new HandlerThread("CameraBackground");mBackgroundThread.start();mBackgroundHandler = new Handler(mBackgroundThread.getLooper());}/*** Stops the background thread and its {@link Handler}.*/private void stopBackgroundThread() {mBackgroundThread.quitSafely();try {mBackgroundThread.join();mBackgroundThread = null;mBackgroundHandler = null;} catch (InterruptedException e) {e.printStackTrace();}}/*** Creates a new {@link CameraCaptureSession} for camera preview.*/private void createCameraPreviewSession() {try {SurfaceTexture texture = mTextureView.getSurfaceTexture();assert texture != null;// We configure the size of default buffer to be the size of camera preview we want.texture.setDefaultBufferSize(mPreviewSize.getWidth(), mPreviewSize.getHeight());// This is the output Surface we need to start preview.Surface surface = new Surface(texture);// We set up a CaptureRequest.Builder with the output Surface.mPreviewRequestBuilder= mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW);mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_MODE,CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE);mPreviewRequestBuilder.addTarget(surface);mPreviewRequestBuilder.addTarget(mImageReader.getSurface());// Here, we create a CameraCaptureSession for camera preview.mCameraDevice.createCaptureSession(Arrays.asList(surface, mImageReader.getSurface()),mCaptureStateCallback, mBackgroundHandler);} catch (CameraAccessException e) {e.printStackTrace();}}/*** Configures the necessary {@link Matrix} transformation to `mTextureView`.* This method should be called after the camera preview size is determined in* setUpCameraOutputs and also the size of `mTextureView` is fixed.** @param viewWidth The width of `mTextureView`* @param viewHeight The height of `mTextureView`*/private void configureTransform(int viewWidth, int viewHeight) {if (null == mTextureView || null == mPreviewSize) {return;}Matrix matrix = new Matrix();RectF viewRect = new RectF(0, 0, viewWidth, viewHeight);RectF bufferRect = new RectF(0, 0, mPreviewSize.getHeight(), mPreviewSize.getWidth());float centerX = viewRect.centerX();float centerY = viewRect.centerY();if (Surface.ROTATION_90 == rotation || Surface.ROTATION_270 == rotation) {bufferRect.offset(centerX - bufferRect.centerX(), centerY - bufferRect.centerY());matrix.setRectToRect(viewRect, bufferRect, Matrix.ScaleToFit.FILL);float scale = Math.max((float) viewHeight / mPreviewSize.getHeight(),(float) viewWidth / mPreviewSize.getWidth());matrix.postScale(scale, scale, centerX, centerY);matrix.postRotate((90 * (rotation - 2)) % 360, centerX, centerY);} else if (Surface.ROTATION_180 == rotation) {matrix.postRotate(180, centerX, centerY);}Log.i(TAG, "configureTransform: " + getCameraOri(rotation, mCameraId) + " " + rotation * 90);mTextureView.setTransform(matrix);}public static final class Builder {/*** 预览显示的view，目前仅支持textureView*/private TextureView previewDisplayView;/*** 是否镜像显示，只支持textureView*/private boolean isMirror;/*** 指定的相机ID*/private String specificCameraId;/*** 事件回调*/private Camera2Listener camera2Listener;/*** 屏幕的长宽，在选择最佳相机比例时用到*/private Point previewViewSize;/*** 传入getWindowManager().getDefaultDisplay().getRotation()的值即可*/private int rotation;/*** 指定的预览宽高，若系统支持则会以这个预览宽高进行预览*/private Point previewSize;/*** 最大分辨率*/private Point maxPreviewSize;/*** 最小分辨率*/private Point minPreviewSize;/*** 上下文，用于获取CameraManager*/private Context context;public Builder() {}public Builder previewOn(TextureView val) {previewDisplayView = val;return this;}public Builder isMirror(boolean val) {isMirror = val;return this;}public Builder previewSize(Point val) {previewSize = val;return this;}public Builder maxPreviewSize(Point val) {maxPreviewSize = val;return this;}public Builder minPreviewSize(Point val) {minPreviewSize = val;return this;}public Builder previewViewSize(Point val) {previewViewSize = val;return this;}public Builder rotation(int val) {rotation = val;return this;}public Builder specificCameraId(String val) {specificCameraId = val;return this;}public Builder cameraListener(Camera2Listener val) {camera2Listener = val;return this;}public Builder context(Context val) {context = val;return this;}public Camera2Helper build() {if (previewViewSize == null) {Log.e(TAG, "previewViewSize is null, now use default previewSize");}if (camera2Listener == null) {Log.e(TAG, "camera2Listener is null, callback will not be called");}if (previewDisplayView == null) {throw new NullPointerException("you must preview on a textureView or a surfaceView");}if (maxPreviewSize != null && minPreviewSize != null) {if (maxPreviewSize.x < minPreviewSize.x || maxPreviewSize.y < minPreviewSize.y) {throw new IllegalArgumentException("maxPreviewSize must greater than minPreviewSize");}}return new Camera2Helper(this);}}private class OnImageAvailableListenerImpl implements ImageReader.OnImageAvailableListener {private byte[] y;private byte[] u;private byte[] v;private ReentrantLock lock = new ReentrantLock();@Overridepublic void onImageAvailable(ImageReader reader) {Image image = reader.acquireNextImage();// Y:U:V == 4:2:2if (camera2Listener != null && image.getFormat() == ImageFormat.YUV_420_888) {Image.Plane[] planes = image.getPlanes();// 加锁确保y、u、v来源于同一个Imagelock.lock();// 重复使用同一批byte数组，减少gc频率if (y == null) {y = new byte[planes[0].getBuffer().limit() - planes[0].getBuffer().position()];u = new byte[planes[1].getBuffer().limit() - planes[1].getBuffer().position()];v = new byte[planes[2].getBuffer().limit() - planes[2].getBuffer().position()];}if (image.getPlanes()[0].getBuffer().remaining() == y.length) {planes[0].getBuffer().get(y);planes[1].getBuffer().get(u);planes[2].getBuffer().get(v);camera2Listener.onPreview(y, u, v, mPreviewSize, planes[0].getRowStride());}lock.unlock();}image.close();}}}

然后初始化后绑定布局

texture_preview.viewTreeObserver.addOnGlobalLayoutListener(this)override fun onGlobalLayout() {texture_preview.viewTreeObserver.removeOnGlobalLayoutListener(this)if (!checkPermissions(NEEDED_PERMISSIONS)) {ActivityCompat.requestPermissions(this, NEEDED_PERMISSIONS, ACTION_REQUEST_PERMISSIONS)} else {initCamera()}}

初始化相机

camera2Helper = Camera2Helper.Builder().cameraListener(this).maxPreviewSize(Point(1920, 1080)).minPreviewSize(Point(1280, 720)).specificCameraId(CAMERA_ID).context(applicationContext).previewOn(texture_preview).previewViewSize(Point(texture_preview.width,texture_preview.height)).rotation(windowManager.defaultDisplay.rotation).build()camera2Helper.start()

然后在相机的回调里面，我们看看做了什么，首先是相机启动的时候

override fun onCameraOpened(cameraDevice: CameraDevice?,cameraId: String?,previewSize: Size?,displayOrientation: Int,isMirror: Boolean) {Log.i("Wzz", "onCameraOpened: previewSize = ${previewSize?.width} x ${previewSize?.height}")mDisplayOrientation = displayOrientationisMirrorPreview = isMirroropenedCameraId = cameraId}

然后重要的就是preview里面返回的yuv原始数据

if (!this::nv21.isInitialized) {nv21 = ByteArray(stride * previewSize!!.height * 3 / 2)}// 回传数据是YUV422if (y!!.size / u!!.size == 2) {ImageUtil.yuv422ToYuv420sp(y, u, v, nv21, stride, previewSize!!.height)} else if (y.size / u.size == 4) {ImageUtil.yuv420ToYuv420sp(y, u, v, nv21, stride, previewSize!!.height)}val yuvImage = YuvImage(nv21, ImageFormat.NV21, stride, previewSize!!.height, null)

然后转换nv21

YuvImage yuvimage = new YuvImage(_data, ImageFormat.NV21,_previewSize.getWidth(), _previewSize.getHeight(), null);

再继续转换为rgb_565格式

ByteArrayOutputStream baos = new ByteArrayOutputStream();BitmapFactory.Options bfo = new BitmapFactory.Options();bfo.inPreferredConfig = Bitmap.Config.RGB_565;Bitmap _currentFrame = BitmapFactory.decodeStream(new ByteArrayInputStream(baos.toByteArray()), null, bfo);

如果需要转换方向

Matrix matrix = new Matrix();if(mIsVertical){matrix.postRotate(90);matrix.preScale(-1, 1); //Android内置人脸识别的图像必须是头在上,所以要做旋转变换// We rotate the same Bitmap_currentFrame = Bitmap.createBitmap(_currentFrame, 0, 0,_previewSize.getWidth(), _previewSize.getHeight(), matrix, false);}

然后就可以用faceDetector来进行检测了

FaceDetector d = new FaceDetector(_currentFrame.getWidth(),_currentFrame.getHeight(),1);Face[] faces = new Face[1];d.findFaces(_currentFrame, faces);

接下来就可以自己对face进行判断处理进行自己需要的操作了

然后介绍如何绘制人脸位置方框

private fun handleFaces(face: FaceDetector.Face) {var pointF = PointF()face.getMidPoint(pointF)mFacesRect.clear()val widthp = texture_preview.width/heightval heightP = texture_preview.height/widthval spec = face.eyesDistance() / heightPval bounds = pointFval y = bounds.y * heightPval x = bounds.x * widthpval left = x - specval top = y - specval right = x + specval bottom = y + specval rawFaceRect = RectF(left.toFloat(), top.toFloat(), right.toFloat(), bottom.toFloat())// val rawFaceRect3 = RectF(0f, 0f, 10f, 20f)val rawFaceRect3 = RectF( 0f,0f,texture_preview.width.toFloat(),texture_preview.height.toFloat())mFaceDetectMatrix.mapRect(rawFaceRect)Log.d("wzz","prewview: ${width} * ${height}")Log.d("wzz","texture_preview: ${texture_preview.width} * ${texture_preview.height}")Log.d("wzz","texture_preview: ${texture_preview.top} * ${texture_preview.left} --- ${texture_preview.right}---${texture_preview.bottom}")val resultFaceRect = rawFaceRectmFacesRect.add(resultFaceRect)mFacesRect.add(rawFaceRect3)Log.d("wzz","原始人脸位置: ${bounds.x} * ${bounds.y} ----${face.eyesDistance()} ")Log.d("wzz","转换后人脸位置: ${resultFaceRect.width()} * ${resultFaceRect.height()} ${resultFaceRect.left} ${resultFaceRect.top} ${resultFaceRect.right} ${resultFaceRect.bottom} ")runOnUiThread {faceView.setFaces(mFacesRect)}}

然后具体的参数，大家就可以调试着玩了，

后续会推出人脸识别opencv方案，

1.最近要研究一下opencv 2d人脸模型转3d

2.以及arcore的人脸增强玩法

大家有什么问题可以评论讨论，也可以直接联系博主