attempts to add my optional leadin (#2)

* attempts to add my optional leadin

speed will return to normal an optional number of seconds before the subs appear. Has worked for me so far, would you mind testing?

* Update speed-transition.lua

* Update speed-transition.lua

speed-transition.lua

@@ -1,6 +1,7 @@
 lookahead=5  --if nextsub >= lookahead then speedup
 normalspeed=mp.get_property_native("speed")
 speedup=2.5
+leadin=1
 -------------------
 
 state=0
@@ -41,8 +42,8 @@ function add_timers(nextsub)
    if nextsub ~= 0 then
       --make sure we reset the speed on the unlikely case when a timer fires
       --within one second of the next sub
-      if nextsub - 1 > 0 then
-         mp.add_timeout((nextsub-1)/speedup, reset_early)
+      if nextsub - leadin > 0 then
+         mp.add_timeout((nextsub-leadin)/speedup, reset_early)
       else
          restore_normalspeed()
       end
@@ -50,7 +51,7 @@ function add_timers(nextsub)
    elseif nextsub == 0 then
       --search for next sub after time_out seconds, when its position might be known
       if not mp.get_property_native("pause") and set_timeout() - 1 > 0 then
-         mp.add_timeout((time_out-1)/speedup, search_next_sub)
+         mp.add_timeout((time_out-leadin)/speedup, search_next_sub)
       end
    end
 end