Why does android stretch image on (SET_WALLPAPER)?

Question

Java

I don’t understand why there is another resize of the picture when setting it as wallpaper.
I find out the resolution of the display and crop the image to fit it

public void setWallpaper(Bitmap bitmap, List<Integer> size) {

        Log.d(TAG, "width display: " + size.get(0)); // 1280
        Log.d(TAG, "height display: " + size.get(1)); // 720
        Log.d(TAG, "width bitmap: " + bitmap.getWidth()); // 1480
        Log.d(TAG, "height bitmap: " + bitmap.getHeight()); // 720

        Bitmap dstBmp;

        if (bitmap.getWidth() >= bitmap.getHeight()){

            dstBmp = Bitmap.createBitmap(
                    bitmap,
                    bitmap.getWidth()/2 - size.get(0)/2, // x = 100
                    0, // y = 0
                    size.get(0), // width = 1280
                    size.get(1) // height = 720
            );

        } else {

            dstBmp = Bitmap.createBitmap(
                    bitmap,
                    0,
                    size.get(1)/2 - bitmap.getWidth()/2,
                    size.get(0),
                    size.get(1)
            );
        }

        WallpaperManager wm = WallpaperManager.getInstance(getApplicationContext());

        try {
            wm.setBitmap(dstBmp);
        } catch (IOException e) {
            e.printStackTrace();
        }

    }

The picture is stretched and the image quality is terribly lost, maybe I'm not calculating the display resolution correctly?