Convert audio amplitude to Volume envelope

[AugerJ]

Hello.
Is this possible:
apply the actual volume (or gain) of an audio piece
as Volume envelope to another track or item?

[X-Raym]

There was some experimental stuff made by spk77 for that :

Cockos Incorporated Forums - View Single Post - v5.0pre - New ReaScript functions/IDE testing

I think this is the last update of this, not sure

REAPER | Resources

(not in Reapack apparently).

Edit: not sure it is the right script. Let us know if you find it :P

[AugerJ]

Thanks.
This script seems to be the one I needed:
mpl_Generate track volume automation item from audio take.lua

[mpl]

You can merge AI to envelope by right click on envelope, then 'Delete automation item, preserve points'.
Also it is probably better to generate AI from time selection of selected track ignoring takes selection instead direct item/take selection.

[AugerJ]

Originally Posted by mpl

You can merge AI to envelope by right click on envelope, then 'Delete automation item, preserve points'.

Thanks.

Also it is probably better to generate AI from time selection of selected track ignoring takes selection instead direct item/take selection.

Currently I don't have an access to such a script )

By the way, in my case I had to move created AI 43ms left for it to align with the "source" item better.

[woodslanding]

Wow, trying to use this and all I get is a bunch of points at level= -infinity.

Is there some trick to it?

[X-Raym]

Pretty sure you have Fader Sacling actiavted on the track


Try to deactuvate it beforer unning the script


and if this solve the problem, the script would need an update o support it :P(just few lines of code)

[woodslanding]

How would I do that? A search for fader scaling in the action list doesn't turn anything up, and I don't see it in the menus...

[woodslanding]

Changing to Amplitude scaling did not change the results....

I'm using v1.1

EDIT: I right-clicked the envelope and changed its scaling. Now it works!

THANKS!!!!!!!

[woodslanding]

OMG this is an awesome feature!!!

One FR: Could you make it affect the currently selected envelope, instead of always volume??

Heck, maybe I can figure that out myself...

[woodslanding]

oh gosh, stupid easy!

Select an item, select an envelope (even on a different track) and away you go! Envelope must be set to linear mode, NOT fader mode. This is less likely with a non-volume envelope....

Volume is rarely where I want to send this anyway, and I rarely want the destination track the same as the source track...

Thanks MPL for writing this!!

-- @version 1.1
-- @author MPL  (tiny edit by Woodslanding)
-- @description Generate automation item on selected envelope from audio take
-- @website http://forum.cockos.com/showthread.php?t=188335
-- @changelog
--    + respect multiple items
--    + Consolidate undo
--    # fix proper add points positions

  
  for key in pairs(reaper) do _G[key]=reaper[key]  end  
  function m(s) reaper.ShowConsoleMsg(s)end
 
  ---------------------------------------------------------------------------------------------------------------------  
  function Get_take_data(take, window,item_len)
    local sum_t = {}
    local accessor = CreateTakeAudioAccessor(take)
    local src = GetMediaItemTake_Source(take)
    local numch = GetMediaSourceNumChannels(src)
    local rate = GetMediaSourceSampleRate(src)       
    local size = math.ceil(window*rate)
      
    for read_pos = 0, item_len, window do
      local buffer = new_array(size*2)
      local buffer_com = new_array(size*2)
      GetAudioAccessorSamples(
                          accessor , --AudioAccessor
                          rate, -- samplerate
                          numch, -- numchannels
                          read_pos, -- starttime_sec
                          size, -- numsamplesperchannel
                          buffer) --samplebuffer
                          
      -- merge buffers dy duplicating sum/2
        for i = 1, size*numch - 1, numch do
          buffer_com[i] = (buffer[i] + buffer[i+1])/numch
          buffer_com[i+1] = 0
        end
                                            
      -- Get RMS sum in defined range
        local buffer_com_t = buffer_com.table(1,size, true)
        local sum_com = 0
        for i = 1, size do sum_com = sum_com + math.abs(buffer_com_t[i]) end    
        table.insert(sum_t, sum_com)
          
      end
    DestroyAudioAccessor(accessor)

    -- normalize table
      local max_com = 0
      for i =1, #sum_t do max_com = math.max(max_com, sum_t[i]) end
      local com_mult = 1/max_com      
      for i =1, #sum_t do sum_t[i]= sum_t[i]*com_mult  end
      table.insert(sum_t, 1, 0)
      return sum_t
  end
  ---------------------------------------------------------------------------------------------------------------------
  function CalcAI(item, window_ms)
    if not item then return end
    local take =  reaper.GetActiveTake( item )
    if TakeIsMIDI( take ) then return end
        
    local i_pos = GetMediaItemInfo_Value( item, 'D_POSITION' )
    local i_len = GetMediaItemInfo_Value( item, 'D_LENGTH' )    
    if not  window_ms then return end 
       
    local t = Get_take_data(take, window_ms, i_len)
    local track = GetMediaItem_Track(item)
    SetOnlyTrackSelected(track)
    --env =  GetTrackEnvelopeByName( track, 'Volume' )
    env = GetSelectedEnvelope();
    if not env then 
      Main_OnCommand(40406,0) -- show vol envelope
      env =  GetTrackEnvelopeByName( track, 'Volume' )
    end
    local AI_idx = InsertAutomationItem( env, -1, i_pos, i_len )
    for i = 1, #t do InsertEnvelopePointEx( env, AI_idx, (i-1)*window_ms+i_pos, t[i], 0, 0, 0, true ) end
    Envelope_SortPointsEx( env, AI_idx )
    UpdateArrange()
  end
  
  local ret, window_ms =  reaper.GetUserInputs( 'RMS window', 1, '(seconds)', 0.05 )
  if ret then
    Undo_BeginBlock()
    window_ms = tonumber(window_ms)
    for i = 1,  CountSelectedMediaItems( 0 ) do
      local item = GetSelectedMediaItem(0,i-1)
      CalcAI(item, window_ms)
    end
    Undo_EndBlock( 'Generate AI from audio item', 0 )
  end