Someone

module oc_trigger(in,reset,out);
	input in;
	input reset;
	output out;
	reg out;
	integer tmp;
	initial tmp = 0;
	
	always @( posedge in ) begin
			tmp=tmp+1;
			if ( tmp >= 4 ) begin
				out=1;
				tmp=4;
			end
			else 
				out=0;
		end
endmodule