Android开发人脸识别统计人脸数
tanleicsdn 人气:0最近项目需求是统计当前摄像头中的人脸个数,安卓有提供现成的Api,最终实现效果如上图。
分析思路和步奏:
主要使用到的类:SurfaceView、CameraManager、CameraDevice.StateCallback、CameraCaptureSession.StateCallback。
1.通过SurfaceView展示预览区。
2.在SurfaceView创建成功后通过CameraManager获取当前设备可用的摄像头。
3.检测摄像头权限。
4.通过CameraManager打开摄像头。
5.在打开成功的回调中通过CameraDevice创建会话。
6.在会话创建成功的回调方法中创建预览请求。
7.在预览请求的回调方法onCaptureCompleted()方法中获取预览界面中返回的人脸数。
以下是实现步奏:
1.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" android:orientation="vertical"> <SurfaceView android:id="@+id/sv" android:layout_width="match_parent" android:layout_height="0dp" android:layout_weight="1" /> </LinearLayout>
java
cameraManager = (CameraManager) getSystemService(Context.CAMERA_SERVICE); surfaceHolder = sv.getHolder(); surface = surfaceHolder.getSurface();
//获取可用的相机列表 String[] cameraIdList = cameraManager.getCameraIdList();
if (checkSelfPermission(Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) { // TODO: Consider calling // Activity#requestPermissions // here to request the missing permissions, and then overriding // public void onRequestPermissionsResult(int requestCode, String[] permissions, // int[] grantResults) // to handle the case where the user grants the permission. See the documentation // for Activity#requestPermissions for more details. return; }
//获取开启相机的相关参数 CameraCharacteristics characteristics = cameraManager.getCameraCharacteristics(cameraIdList[1]); //可用于判断是否支持人脸检测,以及支持到哪种程度 faceDetectModes = characteristics.get(CameraCharacteristics.STATISTICS_INFO_AVAILABLE_FACE_DETECT_MODES);//支持的人脸检测模式 cameraManager.openCamera(cameraIdList[1], mStateCallback, null);
camera.createCaptureSession(Arrays.asList(surface), new CameraCaptureSession.StateCallback() { @Override public void onConfigured(@NonNull CameraCaptureSession session) { } @Override public void onConfigureFailed(@NonNull CameraCaptureSession session) { } }, new Handler());
CaptureRequest.Builder captureRequest = camera.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW); captureRequest.addTarget(surface); captureRequest.set(CaptureRequest.CONTROL_MODE, CameraMetadata.CONTROL_MODE_AUTO); captureRequest.set(CaptureRequest.STATISTICS_FACE_DETECT_MODE, getFaceDetectMode()); session.setRepeatingRequest(captureRequest.build(),captureCallback,new Handler());
/** * 预览回调 */ private CameraCaptureSession.CaptureCallback captureCallback = new CameraCaptureSession.CaptureCallback() { @Override public void onCaptureStarted(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, long timestamp, long frameNumber) { super.onCaptureStarted(session, request, timestamp, frameNumber); } @Override public void onCaptureProgressed(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, @NonNull CaptureResult partialResult) { super.onCaptureProgressed(session, request, partialResult); } @Override public void onCaptureCompleted(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, @NonNull TotalCaptureResult result) { super.onCaptureCompleted(session, request, result); Face faces[] = result.get(CaptureResult.STATISTICS_FACES); if (faces.length != face) { Log.e("lee", faces.length + "张脸"); } } @Override public void onCaptureFailed(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, @NonNull CaptureFailure failure) { super.onCaptureFailed(session, request, failure); } @Override public void onCaptureSequenceCompleted(@NonNull CameraCaptureSession session, int sequenceId, long frameNumber) { super.onCaptureSequenceCompleted(session, sequenceId, frameNumber); } @Override public void onCaptureSequenceAborted(@NonNull CameraCaptureSession session, int sequenceId) { super.onCaptureSequenceAborted(session, sequenceId); } @Override public void onCaptureBufferLost(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, @NonNull Surface target, long frameNumber) { super.onCaptureBufferLost(session, request, target, frameNumber); } };
以下就是所有代码:
MainActivity.java
package com.zg.lcddemo; import android.Manifest; import android.content.ContentValues; import android.content.Context; import android.content.pm.PackageManager; import android.content.res.Configuration; import android.database.Cursor; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.graphics.ImageFormat; import android.graphics.Rect; import android.graphics.SurfaceTexture; import android.hardware.Camera; import android.hardware.camera2.CameraAccessException; import android.hardware.camera2.CameraCaptureSession; import android.hardware.camera2.CameraCharacteristics; import android.hardware.camera2.CameraDevice; import android.hardware.camera2.CameraManager; import android.hardware.camera2.CameraMetadata; import android.hardware.camera2.CaptureFailure; import android.hardware.camera2.CaptureRequest; import android.hardware.camera2.CaptureResult; import android.hardware.camera2.TotalCaptureResult; import android.hardware.camera2.params.Face; import android.hardware.camera2.params.SessionConfiguration; import android.hardware.camera2.params.StreamConfigurationMap; import android.media.FaceDetector; import android.media.ImageReader; import android.net.Uri; import android.os.Build; import android.os.Bundle; import android.os.Handler; import android.os.HandlerThread; import android.os.Message; import android.provider.MediaStore; import android.util.Log; import android.util.Size; import android.view.Surface; import android.view.SurfaceHolder; import android.view.SurfaceView; import android.view.View; import android.widget.Button; import android.widget.ImageView; import android.widget.Toast; import androidx.annotation.NonNull; import androidx.annotation.RequiresApi; import androidx.appcompat.app.AppCompatActivity; import java.io.BufferedInputStream; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; import java.io.OutputStream; import java.util.ArrayList; import java.util.Arrays; import java.util.Iterator; import java.util.List; import java.util.concurrent.Semaphore; public class MainActivity extends AppCompatActivity { private SurfaceView sv; private SurfaceHolder surfaceHolder; private CameraManager cameraManager; private Surface surface; int[] faceDetectModes; int face; List<Bitmap> bitmaps = new ArrayList<>(); /** * 获取支持的最高人脸检测级别 * * @return */ private int getFaceDetectMode() { if (faceDetectModes == null) { return CaptureRequest.STATISTICS_FACE_DETECT_MODE_FULL; } else { return faceDetectModes[faceDetectModes.length - 1]; } } @RequiresApi(api = Build.VERSION_CODES.M) @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); sv = findViewById(R.id.sv); cameraManager = (CameraManager) getSystemService(Context.CAMERA_SERVICE); surfaceHolder = sv.getHolder(); surface = surfaceHolder.getSurface(); surfaceHolder.addCallback(new SurfaceHolder.Callback() { @RequiresApi(api = Build.VERSION_CODES.M) @Override public void surfaceCreated(SurfaceHolder holder) { try { //获取可用的相机列表 String[] cameraIdList = cameraManager.getCameraIdList(); if (checkSelfPermission(Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) { // TODO: Consider calling // Activity#requestPermissions // here to request the missing permissions, and then overriding // public void onRequestPermissionsResult(int requestCode, String[] permissions, // int[] grantResults) // to handle the case where the user grants the permission. See the documentation // for Activity#requestPermissions for more details. return; } //获取开启相机的相关参数 CameraCharacteristics characteristics = cameraManager.getCameraCharacteristics(cameraIdList[1]); //可用于判断是否支持人脸检测,以及支持到哪种程度 faceDetectModes = characteristics.get(CameraCharacteristics.STATISTICS_INFO_AVAILABLE_FACE_DETECT_MODES);//支持的人脸检测模式 cameraManager.openCamera(cameraIdList[1], mStateCallback, null); } catch (CameraAccessException e) { e.printStackTrace(); } } @Override public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) { } @Override public void surfaceDestroyed(SurfaceHolder holder) { } }); } /** * 相机状态回调 */ private CameraDevice.StateCallback mStateCallback = new CameraDevice.StateCallback() { @Override public void onOpened(@NonNull final CameraDevice camera) { //打开成功,可以获取CameraDevice对象 try { camera.createCaptureSession(Arrays.asList(surface), new CameraCaptureSession.StateCallback() { @Override public void onConfigured(@NonNull CameraCaptureSession session) { try { CaptureRequest.Builder captureRequest = camera.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW); captureRequest.addTarget(surface); captureRequest.set(CaptureRequest.CONTROL_MODE, CameraMetadata.CONTROL_MODE_AUTO); captureRequest.set(CaptureRequest.STATISTICS_FACE_DETECT_MODE, getFaceDetectMode()); session.setRepeatingRequest(captureRequest.build(),captureCallback,new Handler()); } catch (CameraAccessException e) { e.printStackTrace(); } } @Override public void onConfigureFailed(@NonNull CameraCaptureSession session) { } }, new Handler()); } catch (CameraAccessException e) { e.printStackTrace(); } } @Override public void onDisconnected(@NonNull CameraDevice camera) { //断开连接 Toast.makeText(MainActivity.this, "onDisconnected", Toast.LENGTH_SHORT).show(); } @Override public void onError(@NonNull CameraDevice camera, final int error) { //发生异常 Toast.makeText(MainActivity.this, "onError", Toast.LENGTH_SHORT).show(); } }; /** * 预览回调 */ private CameraCaptureSession.CaptureCallback captureCallback = new CameraCaptureSession.CaptureCallback() { @Override public void onCaptureStarted(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, long timestamp, long frameNumber) { super.onCaptureStarted(session, request, timestamp, frameNumber); } @Override public void onCaptureProgressed(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, @NonNull CaptureResult partialResult) { super.onCaptureProgressed(session, request, partialResult); } @Override public void onCaptureCompleted(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, @NonNull TotalCaptureResult result) { super.onCaptureCompleted(session, request, result); Face faces[] = result.get(CaptureResult.STATISTICS_FACES); if (faces.length != face) { Log.e("lee", faces.length + "张脸"); face = faces.length; } } @Override public void onCaptureFailed(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, @NonNull CaptureFailure failure) { super.onCaptureFailed(session, request, failure); } @Override public void onCaptureSequenceCompleted(@NonNull CameraCaptureSession session, int sequenceId, long frameNumber) { super.onCaptureSequenceCompleted(session, sequenceId, frameNumber); } @Override public void onCaptureSequenceAborted(@NonNull CameraCaptureSession session, int sequenceId) { super.onCaptureSequenceAborted(session, sequenceId); } @Override public void onCaptureBufferLost(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, @NonNull Surface target, long frameNumber) { super.onCaptureBufferLost(session, request, target, frameNumber); } }; }
xml
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" android:orientation="vertical"> <SurfaceView android:id="@+id/sv" android:layout_width="match_parent" android:layout_height="0dp" android:layout_weight="1" /> </LinearLayout>
以上就能实现统计当前摄像头下有多少个人脸。
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持。
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