Android 实现无预览拍照功能

矫情吗；* 2024-03-23 20:46 85阅读 0赞

## Android 实现无预览拍照功能 ##

#### 1.权限 ####

需要相机、读写文件、悬浮窗权限

##### 申请相机、读写文件 #####

manifest.xml

<uses-permission android:name="android.permission.CAMERA" />
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

相机、读写文件权限需要动态申请

ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.CAMERA,
            Manifest.permission.WRITE_EXTERNAL_STORAGE}, 101);

##### 悬浮窗权限 #####

<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />
    <uses-permission android:name="android.permission.SYSTEM_OVERLAY_WINDOW" />

需要申请

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
        if (!Settings.canDrawOverlays(this)) {
            startActivityForResult(new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION, Uri.parse("package:" + getPackageName())), 0);
        } else {
            //TODO do something you need
        }
    }

#### 2.布局与使用 ####

##### 布局 #####

<?xml version="1.0" encoding="utf-8"?>
    <androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        xmlns:tools="http://schemas.android.com/tools"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        tools:context=".test1.Main2Activity">
    
        <Button
            android:id="@+id/button"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="拍照"
            app:layout_constraintTop_toTopOf="parent" />
    
    </androidx.constraintlayout.widget.ConstraintLayout>

##### 使用 #####

主要参数

Camera camera;
    WindowManager wm;
    SurfaceView preview;
    String path = Environment.getExternalStorageDirectory().getAbsolutePath();
    File fileTest = new File(path + "/test.jpg");

然后调用

public void onTakePhotoClicked() {
            preview = new SurfaceView(this);
            SurfaceHolder holder = preview.getHolder();
            // deprecated setting, but required on Android versions prior to 3.0
            holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
            holder.addCallback(new SurfaceHolder.Callback() {
                @Override
                //The preview must happen at or after this point or takePicture fails
                public void surfaceCreated(SurfaceHolder holder) {
                    Log.d("zcf", "Surface created");
                    camera = null;
                    try {
                        camera = Camera.open(Camera.CameraInfo.CAMERA_FACING_BACK);
                        Log.d("zcf", "Opened camera");
                        try {
                            camera.setPreviewDisplay(holder);
                        } catch (IOException e) {
                            throw new RuntimeException(e);
                        }
                        camera.startPreview();
                        Log.d("zcf", "Started preview");
                        Log.e("zcf","开始拍照");
                        camera.takePicture(null, null, TestActivity.this);
                    } catch (Exception e) {
                        if (camera != null)
                            camera.release();
                        throw new RuntimeException(e);
                    }
                }
                @Override
                public void surfaceDestroyed(SurfaceHolder holder) {}
                @Override
                public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {}
            });
            wm = (WindowManager)getSystemService(Context.WINDOW_SERVICE);
            WindowManager.LayoutParams params = null;
            if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O) {
                params = new WindowManager.LayoutParams(
                        1, 1, //Must be at least 1x1
                        WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY,
                        0,
                        //Don't know if this is a safe default
                        PixelFormat.UNKNOWN);
            }
            //Don't set the preview visibility to GONE or INVISIBLE
            wm.addView(preview, params);
        }
    
        @Override
        public void onPictureTaken(byte[] bytes, Camera camera) {
            Log.e("zcf", "拍照结束");
            try {
                FileOutputStream fos = new FileOutputStream(fileAdvert);
                fos.write(bytes);
                fos.close();
                Log.e("zcf","保存结束");
                Message message = handler.obtainMessage();
                message.what = 1;
                handler.sendEmptyMessageDelayed(1,1500);
            } catch (FileNotFoundException e) {
                Log.d("zcf", "File not found: " + e.getMessage());
            } catch (IOException e) {
                Log.d("zcf", "Error accessing file: " + e.getMessage());
            }
        }

拍照结束需要把wm给remove掉，要不还是会挡着下边的东西。

#### 3.完整代码 ####

import android.Manifest;
    import android.annotation.SuppressLint;
    import android.content.Context;
    import android.content.Intent;
    import android.graphics.Bitmap;
    import android.graphics.BitmapFactory;
    import android.graphics.Matrix;
    import android.graphics.PixelFormat;
    import android.hardware.Camera;
    import android.os.Build;
    import android.os.Bundle;
    import android.os.Environment;
    import android.os.Handler;
    import android.os.Message;
    import android.provider.Settings;
    import android.util.Log;
    import android.view.OrientationEventListener;
    import android.view.SurfaceHolder;
    import android.view.SurfaceView;
    import android.view.View;
    import android.view.WindowManager;
    import android.widget.Button;
    
    import androidx.annotation.NonNull;
    import androidx.core.app.ActivityCompat;
    
    import com.arcsoft.face.FaceEngine;
    import com.arcsoft.face.FaceFeature;
    import com.arcsoft.face.FaceInfo;
    import com.arcsoft.face.enums.DetectMode;
    import com.arcsoft.face.enums.DetectModel;
    import com.zg.massagerobot.R;
    import com.zg.massagerobot.base.BaseActivity;
    import com.zg.massagerobot.faceserver.CompareResult;
    import com.zg.massagerobot.faceserver.FaceServer;
    import com.zg.massagerobot.utils.ConfigUtil;
    
    import java.io.File;
    import java.io.FileInputStream;
    import java.io.FileNotFoundException;
    import java.io.FileOutputStream;
    import java.io.IOException;
    import java.util.ArrayList;
    import java.util.List;
    import java.util.concurrent.ExecutorService;
    import java.util.concurrent.Executors;
    
    import io.reactivex.Observable;
    import io.reactivex.ObservableEmitter;
    import io.reactivex.ObservableOnSubscribe;
    import io.reactivex.Observer;
    import io.reactivex.android.schedulers.AndroidSchedulers;
    import io.reactivex.disposables.Disposable;
    import io.reactivex.schedulers.Schedulers;
    
    public class Main2Activity extends BaseActivity implements Camera.PictureCallback {
    
        Button button;
        Camera camera;
    
        WindowManager wm;
        SurfaceView preview;
    
        String path = Environment.getExternalStorageDirectory().getAbsolutePath();
        File fileTest = new File(path + "/test.jpg");
    
    
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main2);
    
            ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.CAMERA,
                    Manifest.permission.WRITE_EXTERNAL_STORAGE}, 101);
    
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
                if (!Settings.canDrawOverlays(this)) {
                    Intent intent = new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION);
                    intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                    startActivityForResult(intent, 1);
                } else {
                    //TODO do something you need
                }
            }
    
            FaceServer.getInstance().init(this);
            initOrientate();
    
            button = findViewById(R.id.button);
            button.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    onTakePhotoClicked();
                }
            });
        }
    
        @SuppressLint("HandlerLeak")
        private Handler handler = new Handler() {
            @Override
            public void handleMessage(@NonNull Message msg) {
                super.handleMessage(msg);
                switch (msg.what) {
                    case 1:
                        wm.removeViewImmediate(preview);
                        break;
                }
            }
        };
    
    
        public void onTakePhotoClicked() {
            preview = new SurfaceView(this);
            SurfaceHolder holder = preview.getHolder();
            // deprecated setting, but required on Android versions prior to 3.0
            holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
            holder.addCallback(new SurfaceHolder.Callback() {
                @Override
                //The preview must happen at or after this point or takePicture fails
                public void surfaceCreated(SurfaceHolder holder) {
                    Log.d("zcf", "Surface created");
                    camera = null;
                    try {
                        camera = Camera.open(Camera.CameraInfo.CAMERA_FACING_FRONT);
                        Log.d("zcf", "Opened camera");
                        try {
                            camera.setPreviewDisplay(holder);
                        } catch (IOException e) {
                            throw new RuntimeException(e);
                        }
                        camera.startPreview();
                        Log.d("zcf", "Started preview");
                        Log.e("zcf", "开始拍照");
                        camera.takePicture(null, null, Main2Activity.this);
                    } catch (Exception e) {
                        if (camera != null)
                            camera.release();
                        throw new RuntimeException(e);
                    }
                }
    
                @Override
                public void surfaceDestroyed(SurfaceHolder holder) {
                }
    
                @Override
                public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
                }
            });
            wm = (WindowManager) getSystemService(Context.WINDOW_SERVICE);
            WindowManager.LayoutParams params = null;
            if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O) {
                params = new WindowManager.LayoutParams(
                        1, 1, //Must be at least 1x1
                        WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY,
                        0,
                        //Don't know if this is a safe default
                        PixelFormat.UNKNOWN);
            }
            //Don't set the preview visibility to GONE or INVISIBLE
            wm.addView(preview, params);
        }
    
        @Override
        public void onPictureTaken(byte[] bytes, Camera camera) {
            /*Log.e("zcf", "拍照结束");
            try {
                //图片需要向右旋转90度，然后提取特征比较
                FileOutputStream fos = new FileOutputStream(fileTest);
                fos.write(bytes);
                fos.close();
                Log.e("zcf", "保存结束");
                Message message = handler.obtainMessage();
                message.what = 1;
                handler.sendEmptyMessageDelayed(1, 1500);
            } catch (FileNotFoundException e) {
                Log.d("zcf", "File not found: " + e.getMessage());
            } catch (IOException e) {
                Log.d("zcf", "Error accessing file: " + e.getMessage());
            }*/
    
            Log.e("zcf", "拍照结束");
            //图片需要向右旋转90度，然后提取特征比较
            getPhotoPath(bytes, takePhotoOrientation);
        }
    
    
        @Override
        protected void onDestroy() {
            super.onDestroy();
        }
    
        private ExecutorService threadPool = Executors.newCachedThreadPool();
    
        /**
         * @return 返回路径
         */
        private void getPhotoPath(final byte[] data, final int takePhotoOrientation) {
            threadPool.execute(new Runnable() {
                @Override
                public void run() {
                    try {
                        FileOutputStream fos = new FileOutputStream(fileTest);
                        try {
                            //将数据写入文件
                            fos.write(data);
                        } catch (IOException e) {
                            e.printStackTrace();
                        } finally {
                            try {
                                fos.close();
                            } catch (IOException e) {
                                e.printStackTrace();
                            }
                        }
    
                        //将图片旋转
                        rotateImageView(Camera.CameraInfo.CAMERA_FACING_FRONT, takePhotoOrientation, fileTest.getAbsolutePath());
                    } catch (FileNotFoundException e) {
                        e.printStackTrace();
                    }
                    Log.e("zcf", "保存结束");
                    Message message = handler.obtainMessage();
                    message.what = 1;
                    handler.sendEmptyMessageDelayed(1, 1500);
                }
            });
        }
    
        /**
         * 旋转图片
         *
         * @param cameraId    前置还是后置
         * @param orientation 拍照时传感器方向
         * @param path        图片路径
         */
        private void rotateImageView(int cameraId, int orientation, String path) {
            Bitmap bitmap = BitmapFactory.decodeFile(path);
            Matrix matrix = new Matrix();
            matrix.postRotate(Float.valueOf(orientation));
            // 创建新的图片
            Bitmap resizedBitmap;
    
            if (cameraId == 1) {
                if (orientation == 90) {
                    matrix.postRotate(180f);
                }
            }
            // 创建新的图片
            resizedBitmap = Bitmap.createBitmap(bitmap, 0, 0,
                    bitmap.getWidth(), bitmap.getHeight(), matrix, true);
    
            //新增 如果是前置 需要镜面翻转处理
            if (cameraId == 1) {
                Matrix matrix1 = new Matrix();
                matrix1.postScale(-1f, 1f);
                resizedBitmap = Bitmap.createBitmap(resizedBitmap, 0, 0,
                        resizedBitmap.getWidth(), resizedBitmap.getHeight(), matrix1, true);
    
            }
    
            File file = new File(path);
            //重新写入文件
            try {
                // 写入文件
                FileOutputStream fos;
                fos = new FileOutputStream(file);
                //默认jpg
                resizedBitmap.compress(Bitmap.CompressFormat.JPEG, 100, fos);
                fos.flush();
                fos.close();
                resizedBitmap.recycle();
            } catch (Exception e) {
                e.printStackTrace();
                return;
            }
    
        }
    
        //增加传感器
        private OrientationEventListener mOrientationEventListener;
        //当前角度
        private float mCurrentOrientation = 0f;
        //拍照时的传感器方向
        private int takePhotoOrientation = 0;
    
        /**
         * 初始化传感器方向
         */
        private void initOrientate() {
            if (mOrientationEventListener == null) {
                mOrientationEventListener = new OrientationEventListener(this) {
                    @Override
                    public void onOrientationChanged(int orientation) {
                        // i的范围是0-359
                        // 屏幕左边在顶部的时候 i = 90;
                        // 屏幕顶部在底部的时候 i = 180;
                        // 屏幕右边在底部的时候 i = 270;
                        // 正常的情况默认i = 0;
                        if (45 <= orientation && orientation < 135) {
                            takePhotoOrientation = 180;
                            mCurrentOrientation = -180;
                        } else if (135 <= orientation && orientation < 225) {
                            takePhotoOrientation = 270;
                            mCurrentOrientation = 90;
                        } else if (225 <= orientation && orientation < 315) {
                            takePhotoOrientation = 0;
                            mCurrentOrientation = 0;
                        } else {
                            takePhotoOrientation = 90;
                            mCurrentOrientation = -90;
                        }
    
    
                    }
                };
            }
            mOrientationEventListener.enable();
        }
    }