What is the AudioAccessor Samples Per Buffer limit?

Thonex · 11-05-2018, 09:10 AM

HI Guys,

When trying to run code involving AudioAccessor on longer Items I run into an error:

Test Script.lua:70: bad argument #1 to 'new_array' (invalid size)

It's related to this line:

S_Buffer = reaper.new_array(Samples_Per_Item)

Is there a hard-limit? If so, what is a good workaround to process a larger Item?

This particular Item gives me the error when the size of the take is larger than around 2:30 min at 48K. So roughly around 4,007,040 samples.

Here is the code if interested:
https://forum.cockos.com/showpost.ph...2&postcount=12

Any ideas?

Cheers.

nofish · 11-05-2018, 02:21 PM

The usual approach is to go through the samples in smaller blocks rather than all samples of the take at once so big amounts of memory don't need to be allocated.

Here's an exmple:

Defining the block size
https://github.com/X-Raym/REAPER-Rea...%20RMS.lua#L97

Then looping throu the samples per block:
https://github.com/X-Raym/REAPER-Rea...20RMS.lua#L124

X-Raym · 11-05-2018, 03:24 PM

Or use this code snippet: https://github.com/ReaTeam/ReaScript...%20samples.lua

Highly documented :P

Lokasenna · 11-05-2018, 04:04 PM

For what it's worth, I fiddled with a few different values and didn't notice any sort of performance changes right up until it crashed and refused to entertain the idea.

Thonex · 11-05-2018, 04:46 PM

Thanks everyone!!

Very good info here.

Nice examples!!

I saw this in X-Raym's link:

Code:

-- Break the range into blocks
    local block_size = 65536

Is that "65536" (16bit binary limit) really a good number to use here... or is it imply for nostalgia when used in 32 and 64 bit environments?

Sorry... I'm a musician... I missed that day in class

Thanks!

mpl · 11-05-2018, 10:22 PM

Block size also depending on what resolution you want for further performing FFT of this sample block.

Thonex · 11-06-2018, 10:17 AM

Quote:

Originally Posted by mpl

Block size also depending on what resolution you want for further performing FFT of this sample block.

Thanks mpl.

I'll experiment.

Cheers!

spk77 · 10-02-2019, 12:12 PM

I'm trying to make a rough track navigator and noticed that reaper.GetMediaItemTake_Peaks can break a script when trying to get peak data from very very long takes.

But it's a very nice and efficient function

:

Vagelis · 10-02-2019, 01:22 PM

Quote:

Originally Posted by spk77

I'm trying to make a rough track navigator and noticed that reaper.GetMediaItemTake_Peaks can break a script when trying to get peak data from very very long takes.

But it's a very nice and efficient function

:

Wow this looks great!

spk77 · 10-03-2019, 12:23 PM

Quote:

Originally Posted by Vagelis

Wow this looks great!

Thanks!
I'll create a new thread for the script when all basic things are done.

Testing things:
Left click = play/stop
Right click/drag = move edit cursor (and arrange view)

Thonex · 10-03-2019, 04:32 PM

Quote:

Originally Posted by spk77

I'm trying to make a rough track navigator and noticed that reaper.GetMediaItemTake_Peaks can break a script when trying to get peak data from very very long takes.

How long is very long?

Yeah... I think my limit was 45 seconds (ish).

Cheers,

Andrew K

Xenakios · 10-04-2019, 05:27 AM

Quote:

Originally Posted by Thonex

How long is very long?
Yeah... I think my limit was 45 seconds (ish).

The ReaScript arrays have a maximum length of about 4 million elements (64 bit floating point numbers). Oddly enough that isn't documented anywhere...What you can fit into that array depends on your particular data. It's best to do any processing split into smaller buffers, like was suggested at the beginning of this thread.