Composer Reference Guide R2-2026-2.6.9642.28010

R3 2025

Codename: Autodrome — v2.3.9414 (patch v2.3.9511) — released 2025-10-10.

The "Autodrome" release introduces the new audio mixer architecture, NVENC hardware encoding for File Targets (HEVC and AV1 included), and the Switcher Input for cut / crossfade between sources or scenes. Performance work focused on rendering only the inputs in active use.

Highlights:

  • New audio mixer with channel strips, AUX / BUS, SEND, MUTE, pre / post VU metering.
  • NVENC hardware acceleration for File Recorder Target — HEVC (H.265), AV1, lossless 4:4:4.
  • Switcher Input — cut / crossfade between sources or scenes; multiviewer output (2+8 or 2+13) with tally and labels.
  • HEVC lossless playback, DV / MXF / DNxHD / QuickTime Animation 4:4:4 added to Video File Input.
  • Batch Processor input — drive multi-camera switching from Connectors.
  • .NET upgraded to version 8; AWS g5 instance types verified.

Audio

The new audio mixer is the biggest change in this release:

  • Channel strips with AUX / BUS / SEND, MUTE / SOLO, and pre- / post-fader VU metering.
  • RMS and peak audio levels exposed across inputs and operators.
  • Switcher Input adds cut / crossfade for the audio path with a per-strip stereo VU meter.
  • New Audio Routing operator for 8-channel modification.
  • Per-scene audio: a master volume, a centred VU meter, and a built-in scene chain (low-cut, compressor, limiter).
  • Audio preview is limited to channels 0–1 (stereo) by default; flip to 8-channel through Project Options when needed.

Inputs

  • Switcher Input — cut / crossfade between sources or scenes; multiviewer output (2+8 or 2+13) with tally and labels; 4× overlay support.
  • RTMP Input auto-connect option, on by default.
  • Video File Input adds HEVC lossless (YUV444P) playback, DV, MXF, DNxHD, and QuickTime Animation RGB 4:4:4.
  • Batch Processor — input driving multi-camera switching from Connectors.
  • All inputs gained "Invisible" and "Do not render" advanced options for finer rendering control.
  • Media-file properties (timecode, duration, filename) display on Text Input for live captioning.

Targets

  • RTMP Target adds onFI-style timestamp injection in the outgoing stream and per-stream output-resolution scaling (1×, 0.66×, 0.5×, 0.33×).
  • NDI Target adds alpha-channel support (BGRA 4:4:4:4).
  • File Recorder Target adds NVENC hardware acceleration with H.265 and AV1 codecs, plus lossless HEVC 4:4:4.

Operators

  • Alignment Grid — stroke-width adjustment for finer alignment overlays.

Scripting

  • New HTTP API endpoint /api/media/startmedia for media-file playback control.
  • New IsLinux() helper in the Script Engine.

UI / Desktop

  • Audio mixer layout toggle (Ctrl + M).
  • Backup files now organise into project-named subfolders.
  • Scene preview dimming toggle.
  • Resizable scene-layer name column.
  • Miniature VU meters everywhere — input list, operators list, audio mixer.
  • Tooltips for media asset file names / paths.
  • CAV input frame skip / rewind on Shift+Alt+Right / Left.
  • Layer rename to the input's "short name" via a context-menu shortcut.
  • Layer reorder controls in the context menu (up / down / top / bottom).
  • Decklink snapshot export to the Snapshots folder, included in project export.
  • Configurable VU-meter scale (0, +3 to +18 dB).
  • Smoother scroll-wheel zoom.

Performance

  • NVENC encoder improvements and reduced load on RTMP Target.
  • Internal renderer optimisation — only inputs in active use are rendered, freeing GPU cycles for compositing.

Other

  • Connectors panel shows millisecond-resolution timer and auto-links to its HTTP-API endpoint.
  • .NET upgraded to version 8.
  • AWS g5 instances verified — g5.8xlarge and g5.4xlarge.
  • Supermicro 2RU spec added for on-prem deployments (AMD Epyc 9000, RTX PRO 4000).

Bug fixes

  • Backup-media routine no longer skips some model files.
  • Saving a never-named project no longer raises an exception.
  • Blackmagic Decklink Target v4 no longer crashes on unsupported display modes.
  • Deleting the last layer in a scene no longer causes audio to repeat or render unclear.
  • NDI Target no longer crashes on portrait aspect ratios.
  • Preview-audio desync and unexpected output corrected.
  • Stereo VU-meter visual scale errors fixed.
  • Decklink capture no longer raises a 4K exception on Linux.