/ltxv2-video

name: ltxv2-video
description: Build Lightricks LTX-2 / LTX-2.3 video workflows covering text-to-video, image-to-video, GGUF and bundled checkpoints, distilled model, camera control LoRAs, synchronized audio, two-stage upscaling, and swapping alternate/GGUF base models
globs:
  - "**/*.json"

LTX-2 / LTX-2.3 Video Workflows

Version naming (read this first)

There is no "LTX 3.2" or "LTX2.3" as separate products. The user's shorthand refers to **Lightricks LTX-2.3**, a point release of the LTX-2 family. The lineage is:

• **LTX-Video** (2024): first text-to-video model from Lightricks.
• **LTX-2 / LTX-V2** (Oct 2025): 19B-class DiT audio-video foundation model. Bundled checkpoint `ltx-2-19b-distilled.safetensors`, Gemma 3 12B text encoder.
• **LTX-2.3** (released ~March 2026): **22B**-parameter DiT update. Rebuilt VAE (sharper textures/faces/hair/text), ~4x larger text connector (text projection) for prompt adherence, native 9:16 portrait, LoRA support, HiFi-GAN vocoder for cleaner synchronized audio, up to 4K@50fps / ~20s clips. Apache 2.0. **Distributed primarily as GGUF UNets** (community quants) plus separate VAE / text-encoder / text-projection files, NOT a single bundled checkpoint like LTX-2.

When the user says "LTX3.2" / "LTX2.3", treat it as **LTX-2.3**. This skill covers both LTX-2 (bundled checkpoint path) and LTX-2.3 (GGUF UNet path).

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⭐ Render-verified correct setup (read this FIRST — 2026-06-19)

> The GGUF-UNet + `DualCLIPLoader` + `gemma_3_12B_it_fp4_mixed` path documented later > in this skill (the Aitrepreneur installer path) **produces soft/mushy video with > inaccurate faces and eyes.** It runs, but it is NOT the quality path. The setup > below is the official Comfy-Org template, render-proven sharp (1280×704, accurate > faces, synchronized 48 kHz stereo audio).

Models (exact, render-verified)

| Component | File | Source repo | Folder | Notes | |-----------|------|-------------|--------|-------| | **Checkpoint** | `ltx-2.3-22b-dev.safetensors` (46 GB, max quality) **or** `ltx-2.3-22b-dev-fp8.safetensors` (~23 GB, official VRAM-friendly) | `Lightricks/LTX-2.3` / `Lightricks/LTX-2.3-fp8` | **`checkpoints/`** (NOT `unet/`) | The checkpoint carries the transformer **and** the audio VAE. Loaded by `CheckpointLoaderSimple` + reused by `LTXVAudioVAELoader` + `LTXAVTextEncoderLoader`. | | **Gemma text encoder** | `gemma_3_12B_it_fp8_scaled.safetensors` (13 GB) | `Comfy-Org/ltx-2` → `split_files/text_encoders/` | `text_encoders/` | Use fp8_scaled (unpacked). The Aitrepreneur `fp4_mixed` mirror file is **truncated (5.3 GB vs 9.4 GB) AND a packed-fp4 layout** core can't reshape → `shape [15360,1920] invalid for input 27582328`. | | **Distilled speed LoRA** | `ltx_2.3_22b_distilled_1.1_lora_dynamic_fro09_avg_rank_111_bf16.safetensors` @ **0.5** | `Comfy-Org/ltx-2.3` → `split_files/loras/` | `loras/` | The newer *dynamic rank-111* distilled LoRA — NOT the older `...384-1.1`. | | **Gemma abliterated LoRA** ⭐ | `gemma-3-12b-it-abliterated_lora_rank64_bf16.safetensors` @ **1.0** | `Comfy-Org/ltx-2` → `split_files/loras/` | `loras/` | **Applied to the text-encoder CLIP via a `LoraLoader`. This is the prompt-accuracy / correct-eyes fix.** Missing this = subtly-wrong faces. | | **Spatial upscaler** | `ltx-2.3-spatial-upscaler-x2-1.1.safetensors` | `Lightricks/LTX-2.3` | `latent_upscale_models/` | Used by the stage-2 `LTXVLatentUpsampler`. Use `x2-1.1`, not `x2-1.0`. |

Node stack (the right one)

• **`LTXAVTextEncoderLoader`** (CORE, `comfy_extras/nodes_lt_audio.py`) loads gemma + the **full checkpoint** together via `comfy.sd.load_clip([gemma, ckpt], type=LTXV)`. This is the audio-video encoder driving **both video and audio/voice**. **Do NOT use `DualCLIPLoader(type=ltxv)` + a separate `ltx-2.3_text_projection` file**. That is the legacy video-only path and yields mush.
• **Gemma abliterated LoRA** via a `LoraLoader` (CLIP LoRA) on the encoder output → CLIPTextEncode.
• **Two-stage**: base sample (~768×512) → **`LTXVLatentUpsampler`** (×2 spatial, uses the upscaler model + the checkpoint VAE) → refine sample → **1280×704** output. The upscale is the sharpness. A single-stage graph is visibly softer.
• Guider: the Comfy-Org template uses plain **`CFGGuider` cfg=1** (distilled); the LTXVideo repo example uses **`MultimodalGuider` + `GuiderParameters`** (separate AUDIO/VIDEO) + **`ClownSampler_Beta`** (RES4LYF). Both produce sharp output. The LoRAs + two-stage matter more than the guider.
• **ffmpeg is required** for the final mux: `<comfy-venv>/python -m pip install imageio-ffmpeg`, then reboot. `CreateVideo`/`SaveVideo`/`VHS_VideoCombine` fail with `ffmpeg ... could not be found` otherwise.

Custom nodes

`ComfyUI-LTXVideo` (LTXV* nodes, `MultimodalGuider`, `GuiderParameters`, `LTXVPreprocess`, `LTXVTiledVAEDecode`, `GemmaAPITextEncode`, `LTXFloatToInt`) + `RES4LYF` (`ClownSampler_Beta`, only for the repo-example sampler). `LTXAVTextEncoderLoader`, `ResizeImageMaskNode`, `CreateVideo`, `SaveVideo`, `ManualSigmas`, `LTXVScheduler`, the `Primitive*` nodes are all CORE ComfyUI.

Quality troubleshooting (symptom → cause → fix)

• **Mushy/garbage, no clear subject** → empty positive prompt, or `DualCLIPLoader`+projection text encoder. Fix: set a prompt; use `LTXAVTextEncoderLoader`.
• **Coherent but soft/blurry, faces & eyes slightly wrong** → no two-stage upscale and/or missing the gemma abliterated LoRA and/or the old distilled LoRA. Fix: full two-stage template + both LoRAs above.
• **`status: success` but no video file / `outputs` only has a math or text node** → the output node (SaveVideo/VHS) failed validation and was *silently dropped*; the graph short-circuited. Check the ComfyUI log for `Failed to validate prompt for output N` and fix that node (missing ffmpeg, a broken connection, a model-not-in-list).
• **`DualCLIPLoader` reshape `[15360,1920] invalid for input 27582328`** → wrong/truncated gemma → use `gemma_3_12B_it_fp8_scaled`.
• **`Latent