Camera1

Camera1 API

权限申请

AndroidManifest.xml 记住是 <uses-feature>

<uses-permission android:name="android.permission.CAMERA" />
<uses-feature android:name="android.hardware.camera" />
<uses-feature android:name="android.hardware.camera.autofocus" />

再申请存储权限,反正也要保存图片
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

代码也申请，毕竟android 6.0需要动态申请权限

if (Build.VERSION.SDK_INT>= Build.VERSION_CODES.M) {
            if (ContextCompat.checkSelfPermission(MainActivity.this, Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
                //没有存储权限则申请权限
                ActivityCompat.requestPermissions(MainActivity.this, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, 1);
            }

             if (checkSelfPermission(Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
               //申请相机权限
                requestPermissions(new String[]{Manifest.permission.CAMERA}, 1);
            }
}

拍照步骤

1. 获得Camera 实例 Camera camera;
2. open(int)
3. 获取默认配置 Camera.Parameters parameters = camera.getParameters();
4. 修改参数后（预览分辨率，帧率，拍照分辨率等） camera.setParameters(Camera.Parameters)
5. 调用 setDisplayOrientation(int) 确保预览方向
6. 重要：确保初始化 SurfaceHolder to camera.setPreviewDisplay(SurfaceHolder)；没用SurfaceHolder，Camera 将不会开始预览
7. 重要： 调用camera.startPreview()开始预览
8. 如果你想拍摄图片，调用：takePicture(Camera.ShutterCallback, Camera.PictureCallback, Camera.PictureCallback, Camera.PictureCallback)
9. 当你调用takePicture()后，预览已经停止了，这时还需要调用camera.startPreview()重新预览
10. 调用 stopPreview() 停止预览
11. 重要：应用转向其他界面或其他应用，应立即在 Activity.onPause() 调用release() 恢复在Activity.onResume()调用重新打开

在开发板上调试AHD模组

1. 不能调用takePicture() 获取图片，这样通过YUV压缩出来会有失真。

2. 所以用的在onPreview（）这里取的数据进行压缩保存

代码

package com.example.megcar.camera;

import android.Manifest;
import android.app.Activity;
import android.content.pm.PackageManager;
import android.graphics.Rect;
import android.graphics.YuvImage;
import android.os.Build;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;

import java.io.BufferedOutputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.GregorianCalendar;
import java.util.List;
import java.util.Locale;
import java.util.logging.Handler;

import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.DialogInterface.OnClickListener;
import android.graphics.Bitmap;
import android.graphics.Bitmap.CompressFormat;
import android.graphics.BitmapFactory;
import android.graphics.ImageFormat;
import android.hardware.Camera;
import android.hardware.Camera.AutoFocusCallback;
import android.hardware.Camera.PictureCallback;
import android.hardware.Camera.ShutterCallback;
import android.os.Bundle;
import android.os.Environment;
import android.util.DisplayMetrics;
import android.util.Log;
import android.view.Display;
import android.view.SurfaceHolder;
import android.view.SurfaceHolder.Callback;
import android.view.SurfaceView;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.Toast;

public class MainActivity extends Activity {
    private static final String TAG  = "MainActivity";
    SurfaceView sView;
    SurfaceHolder surfaceHolder;
    int screenWidth = 1280;
    int screenHeight = 720;
    // 定义系统所用的照相机
    Camera camera;
    // 是否在预览中
    boolean isPreview = false;


    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        // 设置全屏
        this.requestWindowFeature(Window.FEATURE_NO_TITLE);
        this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);

        setContentView(R.layout.main);
        // 获取窗口管理器
        DisplayMetrics dm = new DisplayMetrics();
        this.getWindowManager().getDefaultDisplay().getMetrics(dm);
//        screenWidth = metrics.widthPixels;
//        screenHeight = metrics.heightPixels;

        Log.e(TAG, "onCreate: screenWidth = " +  dm.widthPixels + "  screenHeight = " + dm.heightPixels);
        // 获取界面中SurfaceView组件
        sView = (SurfaceView) findViewById(R.id.sView);
        // 设置该Surface不需要自己维护缓冲区
        sView.getHolder().setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
        // 获得SurfaceView的SurfaceHolder
        surfaceHolder = sView.getHolder();
        // 为surfaceHolder添加一个回调监听器
        surfaceHolder.addCallback(new Callback()
        {
            @Override
            public void surfaceChanged(SurfaceHolder holder, int format,
                                       int width, int height)
            {
                Log.e(TAG, "surfaceChanged: " );
                initCamera();
            }

            @Override
            public void surfaceCreated(SurfaceHolder holder)
            {
                // 打开摄像头

            }

            @Override
            public void surfaceDestroyed(SurfaceHolder holder)
            {
                // 如果camera不为null ,释放摄像头
                if (camera != null)
                {

                    Log.e(TAG, "surfaceDestroyed: " );
                    if (isPreview) camera.stopPreview();
                    camera.release();
                    camera = null;
                    isPreview = false;
                }
            }
        });

        if (Build.VERSION.SDK_INT>= Build.VERSION_CODES.M) {
            if (ContextCompat.checkSelfPermission(MainActivity.this, Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
                //没有权限则申请权限
                ActivityCompat.requestPermissions(MainActivity.this, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, 1);
            }
        }
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            if (checkSelfPermission(Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
                requestPermissions(new String[]{Manifest.permission.CAMERA}, 1);
            }
        }

    }

    @Override
    protected void onResume() {
        super.onResume();
//        if (camera == null && isPreview ) {
//            Log.e(TAG, "onResume: startPreview" );
//            initCamera();
//        }
    }

    @Override
    protected void onStop() {
        super.onStop();
        if (camera != null && isPreview ) {
            camera.stopPreview();
            camera = null;
            isPreview = false;
        }
    }

    private void initCamera()
    {
        if (!isPreview)
        {
            // 此处默认打开后置摄像头。
            // 通过传入参数可以打开前置摄像头
            camera = Camera.open(1);  //①
            camera.setDisplayOrientation(90);
            Log.e(TAG, "initCamera: open " );
            List<Camera.Size> pictureSizes = camera.getParameters().getSupportedPictureSizes();


            for (int i=0; i<pictureSizes.size(); i++) {
                Camera.Size pSize = pictureSizes.get(i);
                Log.i(TAG, "----------PictureSize.width = "+pSize.width+"-----------------PictureSize.height = "+pSize.height);
            }

        }
        if (camera != null && !isPreview)
        {
            try
            {
                Camera.Parameters parameters = camera.getParameters();
                // 设置预览照片的大小
                parameters.setPreviewSize(screenWidth, screenHeight);
                // 设置预览照片时每秒显示多少帧的最小值和最大值
               // parameters.setPreviewFpsRange(4, 10);
                // 设置图片格式
                parameters.setPictureFormat(ImageFormat.NV21);
                // 设置JPG照片的质量
               // parameters.set("jpeg-quality", 80);
                // 设置照片的大小
                parameters.setPictureSize(screenWidth, screenHeight);

                List<String> focusModes = parameters.getSupportedFocusModes();
                for (String mode : focusModes) {
                    if (mode.equals(Camera.Parameters.FOCUS_MODE_AUTO)) {
                        parameters.setFocusMode(Camera.Parameters.FOCUS_MODE_AUTO);
                        break;
                    }
                }
                camera.setParameters(parameters);
                camera.addCallbackBuffer(new byte[((screenWidth * screenHeight) * ImageFormat.getBitsPerPixel(ImageFormat.NV21)) / 8]);
                camera.setPreviewCallbackWithBuffer(new Camera.PreviewCallback() {
                    @Override
                    public void onPreviewFrame(byte[] data, Camera camera) {
                       // Log.e(TAG, "onPreviewFrame " );
                        if (take_picture) {
                            Log.e(TAG, "onPreviewFrame:take_picture " );
                            final byte[] yuv = data;
                            new Thread(new Runnable() {
                                @Override
                                public void run() {
                                    SaveNV21Bitmap(yuv);
                                }
                            }).start();
                            take_picture = false;
                        }
                        camera.addCallbackBuffer(new byte[data.length]);
                    }
                });

                // 通过SurfaceView显示取景画面
                camera.setPreviewDisplay(surfaceHolder);  //②
                // 开始预览

                camera.startPreview();  //③
                Log.e(TAG, "initCamera: startPreview" );
            }
            catch (Exception e)
            {
                e.printStackTrace();
            }


            isPreview = true;
        }
    }

    private boolean take_picture = false;

    public void capture(View source)
    {
//        if (camera != null)
//        {
//            // 控制摄像头自动对焦后才拍照
//            camera.autoFocus(autoFocusCallback);  //④
//        }
//        camera.takePicture(null, null, new Camera.PictureCallback(){
//            @Override
//            public void onPictureTaken(byte[] data, Camera mcamera) {
//                savePicture(data);
//                mcamera.stopPreview();
//                mcamera.startPreview();
//                isPreview = true;
//            }
//        });
        Log.e(TAG, "capture: " );
        take_picture = true;
    }

    AutoFocusCallback autoFocusCallback = new AutoFocusCallback()
    {
        // 当自动对焦时激发该方法
        @Override
        public void onAutoFocus(boolean success, Camera camera)
        {
            if (success)
            {
                Log.e(TAG, "onAutoFocus: sucess" );
                camera.takePicture(null, null, new Camera.PictureCallback(){
                    @Override
                    public void onPictureTaken(byte[] data, Camera mcamera) {
                        savePicture(data);
                        mcamera.stopPreview();
                        mcamera.startPreview();
                        isPreview = true;
                    }
                });
            }
            Log.e(TAG, "onAutoFocus: fail" );

        }

    };

    PictureCallback myJpegCallback = new PictureCallback()
    {
        @Override
        public void onPictureTaken(byte[] data, Camera camera)
        {
            // 重新浏览
            camera.stopPreview();
            camera.startPreview();
            isPreview = true;
        }
    };
    /**
     * get current date and time as String
     * @return
     */
    private static final String getDateTimeString() {
        final GregorianCalendar now = new GregorianCalendar();
        return new SimpleDateFormat("yyyy-MM-dd-HH-mm-ss", Locale.US).format(now.getTime());
    }

    private File getCaptureFile() {
        File dir = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM),"Camera1");
        Log.d(TAG, "path=" + dir.toString());
        if (!dir.exists()) {
            dir.mkdir();
        }
        if (dir.canWrite()) {
            return  new File(dir,getDateTimeString() + ".jpg");
        }
        return null;
    }
    private void SaveNV21Bitmap(byte[] data) {

        File pictureFile = getCaptureFile();
        try {
            FileOutputStream filecon = new FileOutputStream(pictureFile);
            YuvImage image = new YuvImage(data, ImageFormat.NV21, screenWidth, screenHeight, null);   //将NV21 data保存成YuvImage
            //图像压缩
            image.compressToJpeg(
                    new Rect(0, 0, image.getWidth(), image.getHeight()),
                    80, filecon);   // 将NV21格式图片，以质量70压缩成Jpeg，并得到JPEG数据流

        }catch (IOException e)
        {
            e.printStackTrace();
        }

    }
    public void saveByteToImage(final byte[] data,File file) {
        if (data == null || file == null)
            return;
        Bitmap bitmap = BitmapFactory.decodeByteArray(data,0,data.length);
        try {
            FileOutputStream fos = new FileOutputStream(file);
            bitmap.compress(Bitmap.CompressFormat.PNG,85,fos);
        }catch (FileNotFoundException e){
            Log.e(TAG, "saveByteToImage: " + e.getMessage() );
        }
    }

    private void savePicture(byte[] data) {
        File pictureFile = getCaptureFile();
        BufferedOutputStream bos = null;
        try {
                bos = new BufferedOutputStream(new FileOutputStream(pictureFile));
            bos.write(data);
            bos.flush();
            Toast.makeText(this,"拍照成功",Toast.LENGTH_SHORT).show();
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            if(bos!=null){
                try {
                    bos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

}