2026 · REAPER delivery tool

AutoTrim Exporter

I designed and built AutoTrim Exporter, a REAPER tool that turns layered sound effects into trimmed, named audio files and checks each delivery.

Designer and developer · Lua ReaScript · ReaImGui · REAPER 7.37+ · Windows, macOS and Linux

Download the current release Release hub

AutoTrim Exporter 3.4.3 Export screen with the selected items, delivery format, render mode and the file preview

From selection to delivered files

A sound effect can span several tracks. AutoTrim collects those layers and prepares the export without rearranging the timeline.

  1. Select the item that defines the sound.
  2. Use Select across tracks to include overlapping layers while leaving unrelated long items out.
  3. Choose the delivery profile and review the Preflight checks.
  4. Render the files, with naming, versioning and a report for the batch.

Interface tour recorded in v3.4.3. The screenshots on this page show that version; current builds are in the release hub.

Trimming, delivery profiles and Preflight

Analysis runs on an unnormalised, uncompressed intermediate render.

AutoTrim Exporter 3.4.3 Trim and fades screen with adaptive silence, render-pass and boundary controls

Trim & fades

Preserving the start and tail

Adaptive silence finds the start and the tail separately, with a pre-roll and up to three render passes. Per-item delivery in 3.4.3 renders through a time-selection window, so the timeline items are left alone.

AutoTrim Exporter 3.4.3 Format and delivery screen with profiles, WAV format and channel controls

Format & delivery

Reusable delivery settings

A profile holds format, loudness rules, destination, naming and metadata. Delivered files can be WAV, FLAC, OGG or MP3.

AutoTrim Exporter 3.4.3 Preflight screen showing the render mode, blockers and monitoring differences

Preflight

Checking before export

Preflight identifies settings that block export and explains differences between the monitored sound and the chosen render mode.

Delivery history and regression checks

History records each file’s path, duration and available Peak, RMS and LUFS-I measurements. Files can be played, located or copied from the list. Loudness measurement requires the optional SWS extension.

Project isolation
An export stays bound to the REAPER project tab it started from, including while restoring temporary render settings.
Files and Undo
New-version delivery refuses last-moment collisions and never silently replaces project source media. With backups on, Undo restores a replaced file.
Tested for 3.4.3
The v3.4.3 release checks passed 161 engine regression scenarios and 78 frontend checks. The suite caught all 35 deliberately introduced faults.
AutoTrim Exporter 3.4.3 History screen with verified files, lengths, loudness measurements and file actions

History, in a demo project with synthetic audio and fictional file names.