Find Multiple Shapes

the image has random shapes filled with 0s, separated by 1s. Find all the shapes. Each shape is represented by coordinates of all the elements inside.

Similar as LC 200

public class Main {
    public List<List<Integer>> findMultipleShapes(int[][] board)
    {
        List<List<Integer>> result = new ArrayList<>();
        for(int i = 0; i< board.length; i++)
        {
            for(int j = 0; j< board[0].length; j++)
            {
                if(board[i][j] == 0)
                {
                    List<Integer> shape = new ArrayList<Integer>();
                    dfs(board, i, j, shape);
                    result.add(shape);
                }
            }
        }
        return result;
    }

    public void dfs(int[][] board, int x, int y, List<Integer> shape)
    {
        if(!isBound(board, x, y))
        {
            return;
        }
        if(board[x][y] == 1)
        {
            return;
        }
        shape.add(x);
        shape.add(y);
        board[x][y] = 1;

        dfs(board, x-1, y, shape);
        dfs(board, x+1, y, shape);
        dfs(board, x, y-1, shape);
        dfs(board, x, y+1, shape);
    }

    public boolean isBound(int[][] board, int x, int y)
    {
        return x>=0 && x<board.length && y>=0 && y<board[0].length;
    }
}