Manual Exposure Control for Video Recording

--[[
@title Video Exp Ctrl v3.1
 
original script by fudgey 2010/08/23
http://chdk.setepontos.com/index.php?topic=5295.msg68622#msg68622
modified 2013/11/29 by waterwingz & msl
 
@param     t Starting Tv (sec)
  @default t 3
  @values  t 1/30 1/60 1/100 1/200 1/400 1/640 1/800 1/1000 1/1250 1/1600 1/2000
@param     a Starting Av (f-stop)
  @default a 7
  @values  a 1.8 2.0 2.2 2.6 2.8 3.2 3.5 4.0 4.5 5.0 5.6 6.3 7.1 8.0
@param   p Starting ISO 
  @default p 1
  @values  p 80 100 200 400 800 1250 1600
@param     q ISO Max
  @default q 4
  @values  q 100 200 400 800 1250 1600 3200
@param     s Show Start Message ?
  @default s 1
  @range   s 0 1
@param     d Debug Mode ?
  @default d 0
  @range   d 0 1
--]]
 
require("drawings")
props=require("propcase")
 
--  ========================== Functions ================================= 
 
function restore()
  if ( get_movie_status() == 4 ) then
    if ( vbutton == 1 ) then press("video") sleep(500) release("video")
    else press("shoot_full") sleep(250) release("shoot_full") end
  end
  set_aelock(0)
  set_console_autoredraw(0)
end
 
tv_ref = {    -- note : tv_ref values set 1/2 way between shutter speed values
     464,  496,  528,  560,  592,  624,  656,
     688,  720,  752,  784,  816,  848,  880,  912,  944,  976,
    1008, 1040, 1072, 1096, 1129, 1169, 1192, 1225, 1265, 1376  }
 
tv_val = { 
       400,
       471,  511,  542,  567,  607,  638,  669,
       703,  734,  765,  799,  830,  861,  895,  926,  957,  988,
      1022, 1053, 1084, 1118, 1149, 1180, 1214, 1245, 1276 }
 
tv_str = {
      "err",
      "1/30", "1/40", "1/50", "1/60", "1/80", "1/100", "1/125",
     "1/160", "1/200", "1/250","1/320","1/400","1/500","1/640","1/800","1/1000","1/1250",
    "1/1600","1/2000","1/2500","1/3200","1/4000","1/5000","1/6400","1/8000","1/10000","hi"  }
 
function print_tv(val)
    if ( val == nil ) then return("-") end
    local i = 1
    while (i <= #tv_ref) and (val > tv_ref[i]) do i=i+1 end
    return tv_str[i]
end
 
av_table = {163, 192, 218, 254, 285, 322, 347, 384, 417, 446, 477, 510, 543, 576, 609, 638, 664, 710, 731, 768}
 
function print_av(val)
    if ( val == nil ) then return("-") end
    local fstop=av96_to_aperture(val)
    return((fstop/1000).."."..(fstop%1000)/100)
end
 
sv_table = { 380, 411, 507, 603, 699, 795, 891 } 
function print_sv(val)
    if ( val == nil ) then return("-") end
    return( ((iso_real_to_market(sv96_to_iso(val))+5)/10)*10 )
end
 
function screen_w()     -- lookup table for 480 px screen
    local cams = "ixus110_sd960|ixus200_sd980|ixus240_elph320hs|ixus300_sd4000|ixus310_elph500hs|ixus1000_sd4500|sx1|sx210is|sx220hs|sx230hs"
    return string.find(cams, get_buildinfo().platform) and 480 or 360
end
 
function help_screen()
    local x = screen_w()/2 - 132
    local help_msg = { "HELP SCREEN","FUNC/SET : start/stop video","\017 \016 : change field", "\030 \031 : change value",  "MENU : exit", "FULLPRESS : exit", "Press any key to start", " "}
    local i=1
    while (i < #help_msg) do 
        msg = "                          "..(help_msg[i]).."                          "
        inx = string.find(msg,":")
        if (inx ~= nil) then
            draw.add( "string", x, i*16+64, string.sub(msg, inx-12, inx+18), "red","white")
        else
            draw.add( "string", x, i*16+64, string.sub(msg, (#msg/2)-12, (#msg/2)+18),"white", "blue")
        end
        i=i+1
    end
    rec,vid,mode=get_mode()
    if (vid ~= true) then
        msg ="                           ".."**Camera not in video mode**".."                          "    
        draw.add( "string", x, i*16+64, string.sub(msg, (#msg/2)-12, (#msg/2)+18), "yellow","red")
    end
    repeat
        draw.overdraw()
        wait_click(100)
    until not(is_key("no_key"))
    draw.clear()
end
 
function draw_box()
  local fg, bg = "blue" , "black"
  local w = box_width
  local h = box_height
  --if (gb ~= "trans") then 
  draw.add("rectf",  xpos-1,     ypos-6, xpos+w+1, ypos+h+1, bg, bg)
  --end
  draw.add("string", xpos,       ypos-6, "   Tv     Av    Sv", fg, bg)
  draw.add("line",   xpos,       ypos,   xpos+20,   ypos,   fg)
  draw.add("line",   xpos+45,    ypos,   xpos+70,   ypos,   fg)
  draw.add("line",   xpos+100,   ypos,   xpos+120,  ypos,   fg)
  draw.add("line",   xpos+150,   ypos,   xpos+w,  ypos,   fg)
  draw.add("line",   xpos,       ypos,   xpos,      ypos+h, fg)
  draw.add("line",   xpos+w,     ypos,   xpos+w,    ypos+h, fg)
  draw.add("line",   xpos,       ypos+h, xpos+w,    ypos+h, fg)
end
 
function init_values()
    local fg, bg = "blue" , "black"
    val1=draw.add("string", xpos+6,   ypos+12, " -",   fg, bg)
    val2=draw.add("string", xpos+76,  ypos+12, " -" ,  fg, bg)
    val3=draw.add("string", xpos+120, ypos+12, " -" ,  fg, bg)
end
 
function show_values(Tv, Av, Sv)
    local fg, bg = "white" , "black"
    local fg1, fg2, fg3, fg4, bg1, bg2, bg2 , bg3, bg4
    if(gui_index==0) then fg1 = bg bg1=fg else fg1 = fg bg1=bg end
    if(gui_index==1) then fg2 = bg bg2=fg else fg2 = fg bg2=bg end
    if(gui_index==2) then fg3 = bg bg3=fg else fg3 = fg bg3=bg end
    draw.replace(val1, "string",  xpos+6,  ypos+12, string.sub(" "..print_tv(Tv).."      ",0,8), fg1, bg1)
    draw.replace(val2, "string", xpos+76,  ypos+12, string.sub(" "..print_av(Av).."      ",0,5), fg2, bg2)
    draw.replace(val3, "string", xpos+120, ypos+12, string.sub(" "..print_sv(Sv).."      ",0,5), fg3, bg3)
end
 
function adjust_value(inx, offset)
    local i=1
    if     (inx==0 ) then                                               -- adjust Tv value
        while (i <= #tv_ref) and ( tv96 > tv_ref[i]) do i=i+1 end
        if ( offset > 0 ) then tv96=tv_val[math.min(#tv_val,i+1)]      
        else  tv96=tv_val[math.max(2,i-1)] end
        while (i <= #tv_ref) and ( tv96 > tv_val[i]) do i=i+1 end 
        tv96ret=call_event_proc("SetAE_ShutterSpeed",tv96) 
        if ((tv96ret < tv96-96) or (tv96ret > tv96+96))then             -- clamp values beyond cameras range
            print("clamp", tv96ret)
            tv96=tv96ret 
        end       
        print("new Tv96=",tv96)
    elseif (inx==1) then                                                -- adjust Av value
        av96old = av96
        while (i <= #av_table) and ( av96 > av_table[i]) do i=i+1 end
        if ( offset > 0)  then  
            repeat                                                      -- find next f-stop value the camera will accept
                av96=av_table[math.min(#av_table,i)]
                av96ret=call_event_proc("MoveIrisToAv",av96)
                i=i+1
            until (i > #av_table) or (av96ret>av96old)
            av96=av96ret
        else
            repeat
                i=i-1
                av96=av_table[math.max(1,i)]
                av96ret=call_event_proc("MoveIrisToAv",av96)
            until (i==1) or (av96ret<av96old)
            av96=av96ret
        end
        print("new Av96=",av96)
    elseif (inx==2) then                                                -- adjust Sv value
        while (i <= #sv_table) and ( sv96 > sv_table[i]) do i=i+1 end
        if ( offset > 0)  then  sv96=sv_table[math.min(#sv_table,i+1)]
        else  sv96=sv_table[math.max(1,i-1)] end
        call_event_proc("SetCDSGain",sv96)
        print("new Sv96=",sv96)
    end
end
 
--  ========================== Main Program ================================= 
 
    tv_table    = { 471, 567, 640, 736, 832, 896, 928, 960, 992, 1024, 1056, 1180, 1276}
    tv96target  = tv_table[t+1]
    av_table    = { 171, 192, 218, 265, 285, 322, 347, 384, 417, 446, 477, 510, 543, 576 }
    av96target  = av_table[a+1]
    sv_table    = { 381, 411, 507, 603, 699, 761, 795, 891 }
    sv96target  = sv_table[p+1]
    sv96max     = sv_table[p+2]
 
    xpos =  screen_w()/2 -110               -- msl: 360 or 480 px for default screen position & size (upper left hand corner)
    ypos =  175                             -- msl: above the warning text of the unlimited video recording time
    box_width = 170
    box_height = 32
    set_console_layout(1 ,4, 45, 16 )
 
    bi=get_buildinfo()
    print(string.format("%s %s-%s %s %s %s", bi.version, bi.build_number, bi.build_revision, bi.platform, bi.platsub, bi.build_date))
    version= tonumber(string.sub(string.gsub(get_buildinfo().build_number, "%p", ""), 0, 3))
    if ( tonumber(bi.build_revision) > 0 ) then build = tonumber(bi.build_revision)
    else build = tonumber(string.match(bi.build_number,'-(%d+)$')) end
 
    if ( version < 130) or ( build < 3250)  then 
        error("CHDK 1.3.0 or higher, build 3250 or higher, required")
    end
    if (type(call_event_proc) ~= "function" ) then                      -- need native calls turned on
        error("Lua native calls not enabled")
    end 
    if (call_event_proc("FA.Create") == -1) then                        -- required for event procedures SetAE_ShutterSpeed, MoveIrisToAv, SetCDSGain
        error("FA CREATE failed")
    end
    if (call_event_proc("InitializeAdjustmentSystem") == -1) then
        error("InitializeAdjustmentSystem failed")
    end
 
 -- switch to shooting mode & make sure we are in a video mode
    if ( get_mode() == false ) then
       sleep(1000)
       set_record(1)
       while ( get_mode() == false) do sleep(100) end
    end
    sleep(500)
 
 -- setup splash screen & console 
    set_console_autoredraw(d -1)
    cls()  
    if (s==1) then help_screen() end    
    set_exit_key("no_key")                                              -- use "menu" key to exit so that recording gets stopped if running
    set_draw_title_line(0)
    vbutton = get_video_button()
 
-- startup values 
    set_aelock(1)                                                      -- go to manual exposure mode 
    tv96=call_event_proc("SetAE_ShutterSpeed",tv96target)
    av96=call_event_proc("MoveIrisToAv",av96target)
    call_event_proc("SetCDSGain",sv96target) 
    sv96=sv96target
 
    draw_box()
    init_values()
    gui_index=0
 
    while true do
        show_values(tv96, av96, sv96) 
        repeat
           draw.overdraw()
           wait_click(200)
        until not(is_key("no_key"))
        if     is_pressed("set")   then
            if ( vbutton == 1 ) then press("video") sleep(1000) release("video") sleep(1000)
            else press("shoot_full") sleep(1000) release("shoot_full") sleep(1000) end
        elseif is_pressed("left")  then
            if gui_index > 0 then gui_index = gui_index - 1 end
        elseif is_pressed("right") then
            if gui_index < 2 then gui_index = gui_index + 1 end
        elseif ( is_key("up")) then
           adjust_value(gui_index, 1)
        elseif ( is_key("down")) then
           adjust_value(gui_index, -1)
        elseif ( is_key("zoom_in")) then
            press("zoom_in")
            while(is_pressed("zoom_in")) do sleep(20) end
            release("zoom_in")
        elseif ( is_key("zoom_out")) then
            press("zoom_out")
            while(is_pressed("zoom_out")) do sleep(20) end
            release("zoom_out")
        elseif (is_pressed("menu") or is_pressed("shoot_full"))  then break
        end
    end
    restore()