LTX 2.3 Video Outpaint

Extend a video on any side, and LTX 2.3 paints the new area. Your video goes back on top of the result, and its sound is kept.

How to use it

1. Load your video.

2. Pick a ratio. It opens on 16:9, which turns a phone clip into a wide one. The small button next to the ratios flips portrait and landscape.

3. Press Run.

What you need

• AusBoss nodes 2.3.0 or newer. In ComfyUI-Manager, search "AusBoss". Already have them? Update first.

• The LTX 2.3 models and the two LoRAs:

  • ltx-2.3-22b-dev_transformer_only_fp8_scaled.safetensors → models/diffusion_models · 23.5 GB

  • gemma_3_12B_it_fp8_scaled.safetensors → models/text_encoders · 13.2 GB

  • ltx-2.3_text_projection_bf16.safetensors → models/text_encoders · 2.31 GB

  • LTX23_video_vae_bf16.safetensors → models/vae · 1.45 GB

  • ltx-2.3-22b-distilled-1.1_lora-dynamic_fro09_avg_rank_111_bf16.safetensors → models/loras · 2.74 GB

  • ltx-2.3-22b-ic-lora-outpaint.safetensors → models/loras · 1.31 GB

• The sample clip is in sample_inputs.zip. Put it in ComfyUI/input, or load your own video.

Tips

• Keep the fill color black. Pure black is what the IC-LoRA paints over. Gray or any other color comes back as a flat bar.

• Crop out edges that confuse it. Noise, a frame line or a busy strip along the edge of your clip can make the new area come out strange. Drag the blue handles on Video Crop + Rotate + Pad inward to cut those edges off first.

• It makes 97 frames from IN, about 4 seconds at 24 fps. Drag IN on the timeline to pick the start. On a 60 fps clip, set Every nth to 2 or 3 for more seconds.

• Very dark footage can come back flat. Night or underwater clips can read as a bar. Brighten the clip first (gamma 2.0) and darken the result after (gamma 0.5).

• Out of memory? Lower Megapixels on the video node, or use the smaller int8_convrot transformer in the same Kijai folder.

• Part of the new area still black? Run it again with another seed.

• About 2 minutes a run for a short clip on an RTX 5090, model loading included.

Credits

LTX-2.3 is by Lightricks, under the LTX-2 Community License: companies making US$10M or more a year need a paid license from Lightricks. The ComfyUI files are Kijai's split, and Gemma 3 12B is Google's model, packaged by Comfy-Org. The outpaint IC-LoRA is by oumoumad, under the same license. The sample clip was made with Qwen Image 2.1 and MiniMax H3, and their licenses cover it.

v1.1 (2026-09-30): a smaller workflow, and the new area gets painted on any clip. v1.0 (2026-09-25): first release.

Questions or bugs: GitHub issues or the comments here. More from me on X @Zanzibased and GitHub.