关于按钮点击第二次闪退原因

问题是app启动之后按钮点击一次就自动闪退了，我该如何解决

package com.example.opencv;

import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;

import androidx.appcompat.app.AppCompatActivity;

import org.opencv.android.OpenCVLoader;
import org.opencv.android.Utils;
import org.opencv.core.Core;
import org.opencv.core.Mat;
import org.opencv.imgproc.Imgproc;

import java.io.IOException;

public class deom_1 extends AppCompatActivity {
    private ImageView imageView1,imageView2,imageView3;
    private Button button1;
    private Mat mat1,mat2,result;
    private Bitmap bitmap;

    @Override
    protected void onDestroy() {
        super.onDestroy();
        mat1.release();
        //mat2.release();
        result.release();
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initLoadOpenCV();
        imageView1 = findViewById(R.id.imageView1);
        imageView2 = findViewById(R.id.imageView2);
        imageView3 = findViewById(R.id.imageView3);
        button1 = findViewById(R.id.button1);
        mat1 = new Mat();
       // mat2 = new Mat();
        result = new Mat();
        try {
            mat1 = Utils.loadResource(this, R.drawable.gura1);
            //mat2 = Utils.loadResource(this, R.drawable.gura2);
        } catch (IOException e) {
            e.printStackTrace();
            return;
        }
        button1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                Imgproc.cvtColor(mat1,result,Imgproc.COLOR_RGB2GRAY);
                Imgproc.threshold(result,mat1,125,255,Imgproc.THRESH_BINARY_INV);
                //Imgproc.adaptiveThreshold(result,mat1,225,Imgproc.ADAPTIVE_THRESH_MEAN_C,Imgproc.THRESH_BINARY,13,5);
                //Core.bitwise_or(mat1,mat2,result);
                bitmap = Bitmap.createBitmap(result.width(),result.height(),Bitmap.Config.ARGB_8888);
                Utils.matToBitmap(mat1,bitmap);
                imageView3.setImageBitmap(bitmap);

            }
        });
    }
    public void initLoadOpenCV() {
        boolean success = OpenCVLoader.initDebug();
        if (success) {
            Log.d("init", "initLoadOpenCV: openCV load success");
        } else {
            Log.e("init", "initLoadOpenCV: openCV load failed");
        }
    }

}

这里应该加一个非空判断，如果bitmap是空，肯定会闪退