First with the option Bitmap bitmap compression of the half, then the matrix scaling 0.3f
public class MainActivity extends AppCompatActivity { WebView webView; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); ImageView imageView = findViewById(R.id.image); BitmapFactory.Options newOpts = new BitmapFactory.Options(); newOpts.inJustDecodeBounds = false; newOpts.inSampleSize = 2;//设置缩放比例 //Re-read pictures, pay attention to this time has been set back to false options.inJustDecodeBounds the Bitmap Bitmap = BitmapFactory.decodeResource (getResources (), R.drawable.icon8, newOpts); int width = bitmap.getWidth (); int height = Bitmap .getHeight (); // obtain matrix parameters you want to zoom the matrix matrix = new new the matrix (); matrix.postScale ( 0.3f , 0.3f ); // get new pictures Bitmap newBitMap = Bitmap.createBitmap (Bitmap, 0 , 0 , width, height, Matrix, to true ); imageView.setImageBitmap(newBitMap); } }