WispFX is an AI alpha matte panel for After Effects 2024 or later. It pulls a soft alpha matte from a footage layer, so hair, fur, smoke, glass, liquid and motion blur keep their semi-transparent edges. The matte is rendered on your own NVIDIA GPU, on Windows, and applied to your layer as a luma track matte by default. No green screen, roto or text prompt is needed.
The panel sends the frames of the work area to a local engine. The engine runs Lightricks’ LTX-2.5 Alpha-Gen IC-LoRA model on the GPU and returns 16-bit PNG mattes, which After Effects imports and links to your layer. Matting runs locally: your footage is not uploaded.
Steps
- Install the engine Run setup_engine.bat once. It checks your NVIDIA driver, free disk space and internet connection first, and needs no admin rights.
- Install the panel Quit After Effects, run install_ae_panel.bat, then open Window, Extensions, WispFX.
- Download the models Create a free Hugging Face account, accept the Lightricks licence on the two model pages, connect a read token in the panel (or run HF Login.bat), then click Download. The first download is about 33 to 43 GB, depending on your card.
- Use the layer Select a footage layer in the comp and click Use Layer. WispFX uses the frames inside the work area. Pre-render precomps first.
- Pull the matte Choose a preset (Draft, Balanced, Quality or Max), optionally pick a subject, then click Pull Matte. The time shown is an estimate for your clip and GPU.
- Refine Adjust Matte Refinement (choke, feather, edge detail, Hair Cleanup, Stabilize) and click Update Matte. Refinement runs without re-rendering.
- Apply the matte Choose Apply As: Luma track matte (the default), Matte layer, or RGBA cutout (ProRes 4444 with alpha).
How long a pull takes
Measured on an RTX 4090 with After Effects open, for a 145-frame clip at 1280 by 656: Draft about 20 seconds, Balanced about 30 seconds, Quality about 52 seconds, Max about 2.5 minutes. Cards with less memory are estimates. The Quality preset is the one used for the examples on this site.
Requirements
| Item | Requirement |
|---|---|
| Operating system | Windows 10 or Windows 11, 64-bit. There is no Mac build at launch. |
| GPU | NVIDIA. 8 GB of video memory for Draft, 16 GB for Balanced, 24 GB for Quality, 32 GB or more for Max. |
| NVIDIA driver | Version 570 or newer recommended. Setup warns about older drivers. |
| After Effects | Built for After Effects 2024 and later. Tested on After Effects 2026. |
| Disk space | First model download about 33 to 43 GB, depending on the card. 24 GB cards and Max use Lightricks' official int8 weights (21.5 GB). About 20 to 30 GB stays on disk afterwards. Setup needs 35 to 45 GB free during the first install. |
| Accounts and internet | Internet for setup, the model download and licence checks. A free Hugging Face account that has accepted the Lightricks licence. |
Limits
- Still images are not supported. Use a video file or an image sequence.
- Time-remapped layers follow the timing of the source footage.
- Very sheer fabric can come out more transparent than it should.
- Glass interiors keep faint alpha and the refracted background.
- There is no per-frame spline editing. If the subject is lost on a frame, click it again on that frame or raise Edge Room.
- Max can stall or run slowly on smaller cards. Use it only on 30 GB or more.
- Colour-managed projects (linearised working space, OCIO or ACES) are not verified yet. Check the matte edge in those projects.
- Mattes take disk space. WispFX never deletes them, so remove old renders yourself when no comp uses them.