LTX-2

Tracked

Official Python inference and LoRA trainer package for LTX-2, the first DiT-based audio-video foundation model that generates synchronized audio and video in one model, from Lightricks.

AuthorLightricksOpen Sourced2026-01-03Last CommitUnknown

Overview

LTX-2 is the first DiT-based audio-video foundation model from Lightricks that puts all core capabilities of modern video generation in one model: synchronized audio and video, high fidelity, multiple performance modes, and open access. This repository is the official Python inference and LoRA trainer package; it runs the LTX-2.5 weights published on Hugging Face with pipelines ranging from a fast distilled path to the production-quality DFR (Diffusion Fidelity Rendering) path.

Key Features

  • Synchronized audio and video generation from a single DiT-based model, with distinct fast and production-quality modes
  • Multiple pipelines: DistilledPipeline for a few-step quick start, DFR for production quality, plus TI2Vid, Keyframe, A2Vid, IC-LoRA, and DubIt paths
  • One-file-per-component weight distribution on Hugging Face — download only the transformer, text encoder, VAEs, upscalers, and LoRAs your pipeline needs
  • Resolution defaults of 1024×1536 at 24 fps with UHD 4K output and temporal upscaling rounds
  • LoRA training support alongside inference

Use Cases

  • Generating dialogue or talking-head video with synchronized audio from a text prompt
  • Production text/image-to-video work via DFR with a detailing IC-LoRA and spatial upscaler
  • Keyframe-conditioned video and dubbing workflows through dedicated pipelines

Technical Details

  • The 22B diffusion transformer ships in dev and distilled variants; the distilled transformer runs in far fewer steps and also powers the DFR, IC-LoRA, and DubIt pipelines
  • Text encoding uses a Gemma 4 12B checkpoint fine-tuned for LTX with the projection bundled in; loading version-checks the encoder (gemma4-12b-ltx-v1) against the one the checkpoint was trained with
  • Video decoding offers a diffusion VAE (NADiffusionDecoder) using neighborhood attention — fastest with the Linux/CUDA natten extra, falling back to Triton or eager implementations elsewhere — or a lighter convolutional decoder
  • DFR reuses the distilled transformer and adds a detailing IC-LoRA with extra generated keyframes and a spatial detailing pass; memory-constrained runs can pass --quantization fp8-cast and --offload cpu|disk; dependencies managed with uv sync --extra natten and weights fetched via the Hugging Face CLI