Lshift::
Sendplay,{lshift up}
Keywait,lshift
Return

   OnExit, Exit
   hHookKeybd := DllCall("SetWindowsHookEx" . (A_IsUnicode ? "W" : "A")
      , Int, WH_KEYBOARD_LL := 13
      , Ptr, RegisterCallback("LowLevelKeyboardProc", "Fast")
      , Ptr, DllCall("GetModuleHandle", UInt, 0, Ptr)
      , UInt, 0, Ptr)
   Return

Exit:
   DllCall("UnhookWindowsHookEx", Ptr, hHookKeybd)
   ExitApp

LowLevelKeyboardProc(nCode, wParam, lParam)
{
   Critical
   If NumGet(lParam+0, 0, "UInt") = 160 ; 160 dec vk code LShift
        Return 1
   Return DllCall("CallNextHookEx", Ptr, 0, Int, nCode, UInt, wParam, UInt, lParam)
}

LShift:: return 

#if pict(x, y)
LShift:: return 
#if 
return

pict(ByRef x, ByRef y)
{ 
    ImageSearch, x, y, 0, 0, A_ScreenWidth, A_ScreenHeight, D:\strelka.png
    return !ErrorLevel
}

#if pict(&x,  &y)
LShift:: return 
#if 
return

pict(&x,  &y)
{ 
ImageSearch, x, y, 0, 0,
A_ScreenWidth,
A_ScreenHeight, D:\strelka.png
  return  !ErrorLevel
}
         

loop
{
   ImageSearch, x, y, 0, 0, A_ScreenWidth, A_ScreenHeight, D:\strelka.png
   Hotkey, LShift, Block, % !ErrorLevel ? "On" : "Off"
   Sleep, 50
}  

Block: 
    return

loop
{
   ImageSearch, x, y, 0, 0, A_ScreenWidth, A_ScreenHeight, D:\strelka.png
   if !ErrorLevel
   {
      while GetKeyState("LShift")
         LShift:: return
   }
   Sleep, 50
}