Calculate the area bounded by $x^2+y^2=(\frac{x}{a})^3+(\frac{y}{b})^3$ and $x=0,y=0$

Question

Calculate the area bounded by $x^2+y^2=(\frac{x}{a})^3+(\frac{y}{b})^3$ and $x=0,y=0$

We may assume $a,b>0$. Use the polar coordinate it's equivalent to value $\int_{0}^{\frac{\pi}{2}}\int_0^{\frac{1}{(\frac{\sin{\theta}}{a})^3+(\frac{\cos{\theta}}{b})^3}}rdrd\theta$. And now I can't move forward.
Hint will also be appreciated.