Face++离线版实现拍照进行人脸检测

对Face++提供的安卓离线包中增添拍照预览中的人脸检测。

    用匿名内部类来监听两个按钮的事件，设置了拍照回调函数中的图像比列。

public class MainActivity extends Activity {
    private static final int TAKE_PICTURE = 0;
    private static final int CHOOSE_PICTURE = 1;
    private Bitmap curBitmap;
    private final static int REQUEST_GET_PHOTO = 1;
    ImageView imageView = null;
    HandlerThread detectThread = null;
    Handler detectHandler = null;
    Button button = null;
    FaceDetecter detecter = null;
    HttpRequests request = null;// 在线api
    private static final int SCALE = 5;//照片缩小比例
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        detectThread = new HandlerThread("detect");
        detectThread.start();
        detectHandler = new Handler(detectThread.getLooper());
        imageView = (ImageView) findViewById(R.id.imageview);
        curBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.test2);
        imageView.setImageBitmap(curBitmap);
        
        detecter = new FaceDetecter();
        detecter.init(this, "APIKEY");
        
        request = new HttpRequests("APIKEY","APIKEY_SECRET");
        
        
        Button btndect=(Button)findViewById(R.id.detect);
        Button btnpick=(Button)findViewById(R.id.pick);
        btndect.setOnClickListener(new OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        detectHandler.post(new Runnable() {

                            @Override
                            public void run() {

                                Face[] faceinfo = detecter.findFaces(curBitmap);// 进行人脸检测
                                if (faceinfo == null)
                                {
                                    runOnUiThread(new Runnable() {

                                        @Override
                                        public void run() {
                                            Toast.makeText(MainActivity.this, "未发现人脸信息", Toast.LENGTH_LONG)
                                                    .show();
                                        }
                                    });
                                    return;
                                }
                                
                                //在线api交互
                                try {
                                  
                                    JSONObject result= request.offlineDetect(detecter.getImageByteArray(),detecter.getResultJsonString(), new PostParameters());
          
                                } catch (FaceppParseException e) {
                                    e.printStackTrace();
                                }
                                final Bitmap bit = getFaceInfoBitmap(faceinfo, curBitmap);
                                runOnUiThread(new Runnable() {

                                    @Override
                                    public void run() {
                                        imageView.setImageBitmap(bit);
                                        System.gc();
                                    }
                                });
                            }
                        });
                    }
                });
        btnpick.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                  showPicturePicker(MainActivity.this,false);
            }
        });
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        detecter.release(this);// 释放引擎
    }

    public void showPicturePicker(Context context,boolean isCrop){
        //final boolean crop = isCrop;
        AlertDialog.Builder builder = new AlertDialog.Builder(context);
        builder.setTitle("图片来源");
        builder.setNegativeButton("取消", null);
        builder.setItems(new String[]{"拍照","相册"}, new DialogInterface.OnClickListener() {
            //类型码
            int REQUEST_CODE;
            
            @Override
            public void onClick(DialogInterface dialog, int which) {
                switch (which) {
                case TAKE_PICTURE:
                    Uri imageUri = null;
                    String fileName = null;
                    Intent openCameraIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                        REQUEST_CODE = TAKE_PICTURE;
                        fileName = "image.jpg";
                    imageUri = Uri.fromFile(new File(Environment.getExternalStorageDirectory(),fileName));
                    //指定照片保存路径（SD卡），image.jpg为一个临时文件，每次拍照后这个图片都会被替换
                    openCameraIntent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
                    startActivityForResult(openCameraIntent, REQUEST_CODE);
                    break;
                    
                case CHOOSE_PICTURE:
                    Intent openAlbumIntent = new Intent(Intent.ACTION_GET_CONTENT);
                        REQUEST_CODE = CHOOSE_PICTURE;
                    openAlbumIntent.setDataAndType(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, "image/*");
                    startActivityForResult(openAlbumIntent, REQUEST_CODE);
                    break;

                default:
                    break;
                }
            }
        });
        builder.create().show();
    }
    
    public static Bitmap getFaceInfoBitmap(Face[] faceinfos,
            Bitmap oribitmap) {
        Bitmap tmp;
        tmp = oribitmap.copy(Bitmap.Config.ARGB_8888, true);

        Canvas localCanvas = new Canvas(tmp);
        Paint localPaint = new Paint();
        localPaint.setColor(0xffff0000);
        localPaint.setStyle(Paint.Style.STROKE);
        for (Face localFaceInfo : faceinfos) {
            RectF rect = new RectF(oribitmap.getWidth() * localFaceInfo.left, oribitmap.getHeight()
                    * localFaceInfo.top, oribitmap.getWidth() * localFaceInfo.right,
                    oribitmap.getHeight()
                            * localFaceInfo.bottom);
            localCanvas.drawRect(rect, localPaint);
        }
        return tmp;
    }

    public static Bitmap getScaledBitmap(String fileName, int dstWidth)
    {
        BitmapFactory.Options localOptions = new BitmapFactory.Options();
        localOptions.inJustDecodeBounds = true;
        BitmapFactory.decodeFile(fileName, localOptions);
        int originWidth = localOptions.outWidth;
        int originHeight = localOptions.outHeight;

        localOptions.inSampleSize = originWidth > originHeight ? originWidth / dstWidth
                : originHeight / dstWidth;
        localOptions.inJustDecodeBounds = false;
        return BitmapFactory.decodeFile(fileName, localOptions);
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (resultCode == RESULT_OK) {
            switch (requestCode) {
                case TAKE_PICTURE:
                //将保存在本地的图片取出并缩小后显示在界面上
                Bitmap bitmap = BitmapFactory.decodeFile(Environment.getExternalStorageDirectory()+"/image.jpg");
                curBitmap = ImageTools.zoomBitmap(bitmap, bitmap.getWidth() / SCALE, bitmap.getHeight() / SCALE);
                //由于Bitmap内存占用较大，这里需要回收内存，否则会报out of memory异常
                bitmap.recycle();
                //将处理过的图片显示在界面上，并保存到本地
                imageView.setImageBitmap(curBitmap);
                //ImageTools.savePhotoToSDCard(newBitmap, Environment.getExternalStorageDirectory().getAbsolutePath(), String.valueOf(System.currentTimeMillis()));
                break;
                case REQUEST_GET_PHOTO: {
                    if (data != null) {
                        final String str;
                        Uri localUri = data.getData();
                        String[] arrayOfString = new String[1];
                        arrayOfString[0] = "_data";
                        Cursor localCursor = getContentResolver().query(localUri,
                                arrayOfString, null, null, null);
                        if (localCursor == null)
                            return;
                        localCursor.moveToFirst();
                        str = localCursor.getString(localCursor
                                .getColumnIndex(arrayOfString[0]));
                        localCursor.close();
                        if ((curBitmap != null) && (!curBitmap.isRecycled()))
                            curBitmap.recycle();
                        curBitmap = getScaledBitmap(str, 600);
                        imageView.setImageBitmap(curBitmap);
                    }
                    break;
                }
            }

        }
    }
}

         利用ImageTool里的zoomBitmap

public final class ImageTools {        

/*对相机回调中的照片缩小显示*/

public static Bitmap zoomBitmap(Bitmap bitmap, int width, int height) {
        int w = bitmap.getWidth();
        int h = bitmap.getHeight();
        Matrix matrix = new Matrix();
        float scaleWidth = ((float) width / w);
        float scaleHeight = ((float) height / h);
        matrix.postScale(scaleWidth, scaleHeight);
        Bitmap newbmp = Bitmap.createBitmap(bitmap, 0, 0, w, h, matrix, true);
        return newbmp;
    }

}