FIR filter design with flat passband but equi-ripple stop-band

I am looking for a lowpass FIR filter with flat passband but equi-ripple stopband. In other words, it likes Chebyshev_filter Type II except that it is FIR instead of IIR. Linear-phase is preferred.

Thanks

• Provide more information. – MimSaad May 8 '17 at 8:20

I suggest you the Parks-McClellan method. In Matlab you can use $\tt{firpm}$.
Matlab's (now obsolete function) $\tt{remez}$ also uses this scheme.