谷歌移动视觉：人脸检测在 3 秒后停止答案

【问题标题】：Google Mobile Vision: Face Detection stops after 3 seconds谷歌移动视觉：人脸检测在 3 秒后停止
【发布时间】：2018-04-07 03:40:23
【问题描述】：

人脸检测找到我的脸，然后在 3 秒后圆圈消失。只发生在某些手机上，所以我不确定它为什么会发生。我的代码非常样板：

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_detect);

    detector = new FaceDetector.Builder(getApplicationContext())
            .setTrackingEnabled(false)
            .setProminentFaceOnly(true)
            .setMode(FaceDetector.FAST_MODE)
            .setMinFaceSize((float) 0.60)
            .setLandmarkType(FaceDetector.ALL_CLASSIFICATIONS)
            .setClassificationType(FaceDetector.ALL_CLASSIFICATIONS)

            .build();


    initViews();

}

private void initViews() {
    imgTakePicture = (ImageView) findViewById(R.id.imgTakePic);
    btnTakePicture = (Button) findViewById(R.id.btnTakePicture);
    txtSampleDesc = (TextView) findViewById(R.id.txtSampleDescription);
    txtTakenPicDesc = (TextView) findViewById(R.id.textView);

    btnTakePicture.setOnClickListener(this);
    imgTakePicture.setOnClickListener(this);


}


@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    Log.d(TAG, "onActivityResult: this is resyult");
    if (requestCode == CAMERA_REQUEST && resultCode == RESULT_OK) {
        launchMediaScanIntent();
        try {
            processCameraPicture();
        } catch (Exception e) {
            Toast.makeText(getApplicationContext(), "Failed to load Image", Toast.LENGTH_SHORT).show();
        }
    }
}

private void launchMediaScanIntent() {
    Log.d(TAG, "launchMediaScanIntent: ");
    Intent mediaScanIntent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
    mediaScanIntent.setData(imageUri);
    this.sendBroadcast(mediaScanIntent);
}

private void startCamera() {
    Log.d(TAG, "startCamera: ");
    Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
    Log.d(TAG, "startCamera: 2");
    File photo = new File(Environment.getExternalStorageDirectory(), "/videoDIARY/ReferencePic/photo.jpg");

    imageUri = Uri.fromFile(photo);

    intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);

    startActivityForResult(intent, CAMERA_REQUEST);

}

编辑：好的，我发现这完全是关于设备方向的。在横向模式下的所有设备上都可以正常工作，仅在纵向模式下的某些设备上工作。仍在尝试找出原因，我会在修复时更新！

【问题讨论】：

手机有什么区别？性能、Android版本等？
@MaximTsybanov，它适用于我的 Moto G5 Plus，andorid 版本 7.0，它适用于 HTC 6.0，但不适用于混合了 5.0、5.1、6.0 和 6.1 的三星或 Lg。它似乎更多地与手机面部检测或 Google Play 视觉相关，因为我注意到它在这些手机上的常规相机应用程序中做同样的事情。

标签： android google-play-services face-detection google-vision

【解决方案1】：

好的，事实证明它与面部检测无关，而与 Android 如何保存相机意图图像有关。基本上它会混淆方向，因此您需要检查宽度与高度，以确保它做得正确，如果没有则旋转它。以下是我的检查方式：

private Bitmap decodeBitmapUri(Context ctx, Uri uri) throws FileNotFoundException {
    Log.d(TAG, "decodeBitmapUri: ");
    //Toast.makeText(this, "1o" , Toast.LENGTH_LONG).show();
    Log.d(TAG, "initViews1: face detector is ============================ " + detector.isOperational());
    int targetW = 300;
    int targetH = 300;
    BitmapFactory.Options bmOptions = new BitmapFactory.Options();
    bmOptions.inJustDecodeBounds = true;
    bmOptions.inPreferredConfig=Bitmap.Config.RGB_565;
    BitmapFactory.decodeStream(ctx.getContentResolver().openInputStream(uri), null, bmOptions);
    android.hardware.Camera.CameraInfo info = new android.hardware.Camera.CameraInfo();
    android.hardware.Camera.getCameraInfo(Camera.CameraInfo.CAMERA_FACING_FRONT, info);
    int rotation = this.getWindowManager().getDefaultDisplay().getRotation();
    int orientation = this.getResources().getConfiguration().orientation;
    Log.d(TAG, "decodeBitmapUri: OREINTATION is ==================== " + orientation);

    Log.d(TAG, "decodeBitmapUri: CAMERA ROTATION ========================= " + rotation);
    //Camera.Size size = android.hardware.Camera.get


    int photoW = bmOptions.outWidth;
    Log.d(TAG, "decodeBitmapUri: width: " + photoW );
    int photoH = bmOptions.outHeight;
    Log.d(TAG, "decodeBitmapUri:  height: " + photoH);
    Log.d(TAG, "decodeBitmapUri: 4");
    //Toast.makeText(this, "11" , Toast.LENGTH_LONG).show();

    int scaleFactor = Math.min(photoW / targetW, photoH / targetH);
    bmOptions.inJustDecodeBounds = false;
    bmOptions.inSampleSize = scaleFactor;

    /*this is because some phones default a camera Intent to landscape no matter how the phone is held
    * so we check for camera orienatation, then check to see if width is greater than height
    * */

    if(orientation == 1 && (photoW > photoH)){
        return rotate(BitmapFactory.decodeStream(ctx.getContentResolver()
                .openInputStream(uri), null, bmOptions));
    }


    return BitmapFactory.decodeStream(ctx.getContentResolver()
            .openInputStream(uri), null, bmOptions);
}

public static Bitmap rotate(Bitmap bitmap){
    int w = bitmap.getWidth();
    int h = bitmap.getHeight();

    Matrix mtx = new Matrix();
    mtx.postRotate(270);

    return Bitmap.createBitmap(bitmap, 0, 0, w, h, mtx, true);
}

【讨论】：