¿如何处理字节数组中的图像？

Question

I tried this but when I show the bitmap I can not see anything, what I want is to paint a white outline on the original image

Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.dog);

 public byte[] myImagetoBytes(Bitmap bitmap){
        ByteArrayOutputStream stream = new ByteArrayOutputStream();
        bitmap.compress(Bitmap.CompressFormat.PNG, 100, stream);
        return stream.toByteArray();
    }



 byte[] bytes = myImagetoBytes();

 bytes[0] = 1 & 0xff;

 Bitmap bitmap = BitmapFactory.decodeByteArray(bytes, 0, bytes.length);

 this.imageView.setImageBitmap(bitmap);

Answer 1

Not sure what your code is supposed to do, but if you want to draw over a bitmap, you should use Canvas . You create it with its constructor:

Canvas canvas = new Canvas(bitmap);

And then you can use it like this:

 Paint paint = new Paint();
 paint.setColor(Color.GRAY);
 RectF ovalRect = new RectF(0, 0, 10, 10);
 canvas.drawOval(ovalRect, paint);