Flush FX before rendering

[heda]

We have the option to Flush FX on stop.
It can only be activated if Run FX when stopped (good for certain VSTi) is active. If I deactivate it to save CPU when stopped, then Flush FX on stop is grayed out.. and then if you don't use Flush FX on stop... a lot of weird things happen. Even reverb tails being rendered at the beginning of a render.
Can we have Flush FX before rendering. It would never hurt I guess.

[richie43]

+ a zillion. I have been plagued by the reverb or delay at THE BEGINNING of a render before, ant it's maddening. But I have learned that if I "rewind" the cursor to before play starts, or even click somewhere in the timeline where the audio has stopped, I can render without worrying about this. But a more elegant solution would be awesome.

[Quest The Wordsmith]

Originally Posted by richie43

+ a zillion. I have been plagued by the reverb or delay at THE BEGINNING of a render before, ant it's maddening. But I have learned that if I "rewind" the cursor to before play starts, or even click somewhere in the timeline where the audio has stopped, I can render without worrying about this. But a more elegant solution would be awesome.

Sorry bro, I'm not getting you. How do you avoid the reverb in the beginning when rendering? I have this issue too. My solution is to save, exit, then re-open and render.

[Refillable]

I think that is a problem with certain plugins. It happens in REAPER and Logic 7 as well when I use IK CSR. Put the play cursor after the last item in the project before rendering seems to help.

[heda]

I'm trying to move the cursor to the beginning.. or to the end... nothing.. same reverb tail in render.. the only way to fix it for me is setting Flush FX on stop.

[Refillable]

Originally Posted by heda

I'm trying to move the cursor to the beginning.. or to the end... nothing.. same reverb tail in render.. the only way to fix it for me is setting Flush FX on stop.

Does it happen when rendering online when you put the cursor in the beginning/after last item in project?

[heda]

Originally Posted by Refillable

Does it happen when rendering online when you put the cursor in the beginning/after last item in project?

yes it still happens.
I ended up setting up flush FX on stop, so it uses much more CPU even if it is stopped, but having reaper to not use CPU when stopped, stops VSTis from working while stopped. So if I want to test them while being stopped it is a bad thing. It should detect incoming midi signal when stopped and start the engine again until no more midi notes are received and after a reasonable time.. then stop engine again to save CPU.

[IXix]

Yeah, flush before render would be good. I've been caught out a few times so I know to avoid it but it's still a bit of a pain. Would be great to just not have to worry about it.

[DeBased]

Was this ever addressed? Hitting the same thing a lot with H-Reverb and other tails.

[DeBased]

.. thinking about it, it's not that easy - some plugs may for example make permanent noise even with silence fed through it. Think a noisy guitar amp sim etc. So you can't just flush with silence input until you detect silence output.

So I think the best solution is an option to 'pre-render <x> seconds of silence' to flush any tail-processing FX before a render is written to disk.

The time would be user adjustable (5-10 secs might be a good default).


EDIT: thinking about it more, a pre-render might throw off the phase location of any LFO type effects, so the render might sound different than when playing inside Reaper from the start. Maybe that can be avoided, but otherwise you could make the flush option effect-specific (disabled by default). For example, with me H-Reverb is the issue, so just pre-render flushing those instances would avoid most (all?) of my issues.

[karbomusic]

Just an FYI since this almost always for a handful or less of FX, often just one or two, I just automate it out of the mix before the song starts so that there is nothing to render. IOW, let's say a delay with a number of repeats, I just automate the feedback or mix to zero just before the first bar starts.

[DeBased]

Yeah that's an OK workaround, another is to manually play some silence first before every render, or intentionally render a silent section at the start. But I find it easy to forget sometimes and then a whole (often slow) render is wasted. So an automated way would be great.

I don't know if effects actually get notified of a 'new' render or playback. If they do, they could flush their buffers themselves (I've mentioned it to Waves, I'll see what they say). Failing that, Reaper flushing silence before writing a render to disk seems like a good automatic solution.


EDIT: .. actually thinking about it, wouldn't it be nice if Reaper played previews of the render as it's taking place? Say it buffers 5 seconds and then plays them in chunks. That way you would instantly catch if something went wrong at the start (or anywhere in the render for that matter). So you would also catch eg. if you forgot to unmute a track (as I did earlier - twice : ), or if a plugin went rogue (ditto, after an unfreeze : ).

[Gass n Klang]

could we please have this...

[xammax]

+1
Really wish reaper had this feature.

[Melodeath]

Adding my support for this!

[amagalma]

Could you check if this script bypasses the issue? (flushes the FX) :

local version = reaper.GetAppVersion()
local a,b = version:match("(6).(%d%d)")
a,b = tonumber(a), tonumber(b)
if a >= 6 then
  if b < 29 then
    unsupported = true
  elseif b == 29 then
    a, b = version:match("dev(%d%d)(%d%d)")
    a,b = tonumber(a), tonumber(b)
    if a < 5 then
      unsupported = true
    else
      if b < 26 then
        unsupported = true
      end
    end
  end
else
  unsupported = true
end

if unsupported then
  reaper.MB("Unsupported version", "Aborting", 0)
  return reaper.defer(function() end)
end

local proj_len = reaper.GetProjectLength( 0 )
local track1 = reaper.GetTrack( 0, 0 )
local ts_start, ts_end = reaper.GetSet_LoopTimeRange( 0, 0, 0, 0, 0 )

reaper.PreventUIRefresh( 1 )

-- Add dummy item
local dummy_item = reaper.AddMediaItemToTrack( track1 )
local dummy_pos = proj_len + 360
reaper.SetMediaItemInfo_Value( dummy_item, "D_POSITION", dummy_pos )
reaper.SetMediaItemInfo_Value( dummy_item, "D_LENGTH", 30 )
reaper.GetSetMediaItemInfo_String( dummy_item, "P_NOTES", "Dummy item", true )
reaper.GetSet_LoopTimeRange( true, true, dummy_pos, dummy_pos + 30, false )

-- settings
local proj_info = {"RENDER_SETTINGS","RENDER_BOUNDSFLAG"}
local settings_info = {0,2}
local proj_info_str = {"RENDER_FORMAT","RENDER_FORMAT2"}
local settings_info_str = {"bW11ZA==", ""}

-- Get current and set new settings
for i = 1, 2 do
  local cur_val = reaper.GetSetProjectInfo( 0, proj_info[i], 0, false )
  reaper.GetSetProjectInfo( 0, proj_info[i], settings_info[i], true )
  settings_info[i] = cur_val
end
for i = 1, 2 do
  local cur_val = ({reaper.GetSetProjectInfo_String( 0, proj_info_str[i], "", false )})[2]
  reaper.GetSetProjectInfo_String( 0, proj_info_str[i], settings_info_str[i], true )
  settings_info_str[i] = cur_val
end

-- Render with new settings
reaper.Main_OnCommand(41824, 0) -- Render project, using the most recent render settings

-- Set previous settings back
for i = 1, 2 do
  reaper.GetSetProjectInfo( 0, proj_info[i], settings_info[i], true )
end
for i = 1, 2 do
  reaper.GetSetProjectInfo_String( 0, proj_info_str[i], settings_info_str[i], true )
end

-- delete dummy item
reaper.DeleteTrackMediaItem( track1, dummy_item )
-- Restore time selection
reaper.GetSet_LoopTimeRange( true, true, ts_start, ts_end, false )

reaper.PreventUIRefresh( -1 )
reaper.UpdateArrange()
reaper.defer(function() end)

Requires at least v6.29+dev0526 - May 26 2021

[ferropop]

Originally Posted by amagalma

Could you check if this script bypasses the issue? (flushes the FX) :

local version = reaper.GetAppVersion()
local a,b = version:match("(6).(%d%d)")
a,b = tonumber(a), tonumber(b)
if a >= 6 then
  if b < 29 then
    unsupported = true
  elseif b == 29 then
    a, b = version:match("dev(%d%d)(%d%d)")
    a,b = tonumber(a), tonumber(b)
    if a < 5 then
      unsupported = true
    else
      if b < 26 then
        unsupported = true
      end
    end
  end
else
  unsupported = true
end

if unsupported then
  reaper.MB("Unsupported version", "Aborting", 0)
  return reaper.defer(function() end)
end

local proj_len = reaper.GetProjectLength( 0 )
local track1 = reaper.GetTrack( 0, 0 )
local ts_start, ts_end = reaper.GetSet_LoopTimeRange( 0, 0, 0, 0, 0 )

reaper.PreventUIRefresh( 1 )

-- Add dummy item
local dummy_item = reaper.AddMediaItemToTrack( track1 )
local dummy_pos = proj_len + 360
reaper.SetMediaItemInfo_Value( dummy_item, "D_POSITION", dummy_pos )
reaper.SetMediaItemInfo_Value( dummy_item, "D_LENGTH", 30 )
reaper.GetSetMediaItemInfo_String( dummy_item, "P_NOTES", "Dummy item", true )
reaper.GetSet_LoopTimeRange( true, true, dummy_pos, dummy_pos + 30, false )

-- settings
local proj_info = {"RENDER_SETTINGS","RENDER_BOUNDSFLAG"}
local settings_info = {0,2}
local proj_info_str = {"RENDER_FORMAT","RENDER_FORMAT2"}
local settings_info_str = {"bW11ZA==", ""}

-- Get current and set new settings
for i = 1, 2 do
  local cur_val = reaper.GetSetProjectInfo( 0, proj_info[i], 0, false )
  reaper.GetSetProjectInfo( 0, proj_info[i], settings_info[i], true )
  settings_info[i] = cur_val
end
for i = 1, 2 do
  local cur_val = ({reaper.GetSetProjectInfo_String( 0, proj_info_str[i], "", false )})[2]
  reaper.GetSetProjectInfo_String( 0, proj_info_str[i], settings_info_str[i], true )
  settings_info_str[i] = cur_val
end

-- Render with new settings
reaper.Main_OnCommand(41824, 0) -- Render project, using the most recent render settings

-- Set previous settings back
for i = 1, 2 do
  reaper.GetSetProjectInfo( 0, proj_info[i], settings_info[i], true )
end
for i = 1, 2 do
  reaper.GetSetProjectInfo_String( 0, proj_info_str[i], settings_info_str[i], true )
end

-- delete dummy item
reaper.DeleteTrackMediaItem( track1, dummy_item )
-- Restore time selection
reaper.GetSet_LoopTimeRange( true, true, ts_start, ts_end, false )

reaper.PreventUIRefresh( -1 )
reaper.UpdateArrange()
reaper.defer(function() end)

Requires at least v6.29+dev0526 - May 26 2021

Will test this tonight.

For context, this is a thread started in 2014 (and certainly not the first) that is simply asking for RENDERING YOUR FINAL PRODUCT to work properly.

I hate getting snippy like this, but I just can't believe it sometimes. Pick and choose my moments in the Pre forums to subtly bring this up when it seems the devs are working on Render stuff, but it goes unnoticed.

Just to double down : a bug that has existed since 2007 that affects rendering your final product, goes unnoticed in 2021.

[Seldrums]

Yes please. If it were something as simple as a checkbox in options to flush all fx before render, it would always be checked here. Set it and forget it!

[schwa]

This has come up many times. Somewhere there is a long thread about it.

REAPER clears all of its own buffers before rendering, and informs all plugins that they should reset and flush their own buffers. There is a specific, documented VST call for this. If some plugin does not flush its buffers when it handles this call, that's the plugin's fault. There's nothing REAPER can do about it because REAPER does not have access to the plugin's buffers.

The suggestion that REAPER should pump silence through plugins before rendering, to deal with non-compliant plugins, is not workable, and would likely cause problems for compliant plugins while not improving the problem with non-compliant plugins. There's no amount of silence that would be sufficient to guarantee that buffers are empty.

[Melodeath]

I'm glad I found this thread. Reverb and delay tails at the beginning of tracks has been a nuisance for me for years. I can manually clear the buffer by playing back silence before I render, but it's really annoying. Has anyone else come up with a decent solution?

"Flush FX on stop" in preferences doesn't seem to do anything for me

[heda]

Yes... This is still bugging me. I never know if the render is going to be fine. But you always need to listen to the rendered file to check it anyways.
I've found that if a plugin has both a VST version and a VST3 version, the VST3 version works better

[ferropop]

It's almost always Arturia verbs.

[tgraph]

I arm all tracks - arm then off - and that flushes the buffer before rendering...

Seems like that should be an unnecessary step but it's the best I've come up with.