Question

我有一个输入图像sourceMat。

裁剪位于（10,10）的40x40 roi：

Mat roi = sourceMat.submat(10, 50, 10, 50);

创建大小为40x40的位图：

Bitmap tempBitmap = Bitmap.createBitmap(40, 40, thumbnail.getConfig());

将Mat转换为位图并在ImageView中设置：

Utils.matToBitmap(roi, tempBitmap);
imageView.setImageBitmap(tempBitmap );

它不是显示裁剪的图像，而是显示整个原始图像缩小为40x40位图。

我正在使用openCVLibrary320和android sdk 25版

Answer 1

替换：

Bitmap tempBitmap = Bitmap.createBitmap(40, 40, thumbnail.getConfig());

其中任何一个：

Bitmap.createBitmap(40, 40, Bitmap.Config.RGB_565);
Bitmap.createBitmap(40, 40, Bitmap.Config.ARGB_8888);

请参阅documentation。

Answer 2

代码工作正常，代码会有小变化。

  private void showDialog(File pictureFile) {
    // custom dialog
    final Dialog dialog = new Dialog(this, android.R.style.Theme_Black_NoTitleBar_Fullscreen);
    dialog.setContentView(R.layout.image_dialog);
    dialog.setTitle("Image");
    // find the imageview and draw it!
    ImageView image = (ImageView) dialog.findViewById(R.id.image);
    Bitmap thumbnail;
    try {
        thumbnail = MediaStore.Images.Media.getBitmap(
                getContentResolver(), Uri.fromFile(pictureFile));
        cropImage(image, thumbnail);
//            Imgproc.threshold(tmp, tmp, 60, 100, Imgproc.THRESH_BINARY);
//            Utils.matToBitmap(tmp, image1);
//            Imgproc.threshold(tmp, tmp, 1, 255, Imgproc.THRESH_OTSU);
        //using floodfill and watershed to remove noise
//            Mat mask = new Mat(tmp.rows() + 2, tmp.cols() + 2, CvType.CV_8UC1);
//            Imgproc.floodFill(tmp, mask, new Point(tmp.cols() - 10, 10), new Scalar(255.0, 255.0, 255));
        image.setImageBitmap(thumbnail);
    } catch (IOException e) {
        e.printStackTrace();
    }
    Button dialogButton = (Button) dialog.findViewById(R.id.dialogButtonOK);
    // if button is clicked, close the custom dialog
    dialogButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            dialog.dismiss();
        }
    });
    dialog.show();
}

private void cropImage(ImageView image, Bitmap thumbnail) {
    Mat src = new Mat();
    Utils.bitmapToMat(thumbnail, src);
    //converts mat color
    Imgproc.cvtColor(src, src, Imgproc.COLOR_RGBA2BGR);
    Rect roi = new Rect(40, 100, 100, 120);
    Mat cropped = new Mat(src, roi);
    Bitmap tempBmp1 = Bitmap.createBitmap(100, 120, Bitmap.Config.ARGB_8888);
    Utils.matToBitmap(cropped, tempBmp1);
    image.setImageBitmap(tempBmp1);
}

无法将裁剪后的图像（opencv Mat）复制到Bitmap中

2 个答案: