Filter Function Output data width

When we use the "filter(b,a,x)" function the output max data width is limited to the data width of "x"...

e.g. If i have the input "x" as x=floor((2^27-1)*sin(2*pi*1*(0:2^16-1)/sqrt(32))); % where the max data bus width is limited to 28 bits

Now if i do

out = round(filter(b,1,x); % data bus width of b could be less than 28 out(find(out>2^31-1)) = 2^31-1; out(find(out<-2^31)) = -2^31;

The max data bus width would also be 28 bits , but can i make "out" to be having a data bus width of 32 bits