ltx2.md

How to Use

Both LTX-2.3 and LTX-2.5 are supported. The two share a transformer, video VAE and audio VAE architecture; LTX-2.5 drops the video FFN biases, adds a learned keyframe absolute-position embedding, and pairs with a Gemma 4 text encoder instead of Gemma 3. Everything is detected from the weights, so the command lines differ only in which files you pass.

LTX-2.3

Download weights

LTX-2.3

• Download LTX-2.3
  • safetensors: https://huggingface.co/Kijai/LTX2.3_comfy/tree/main/diffusion_models
  • gguf: https://huggingface.co/unsloth/LTX-2.3-GGUF/tree/main
• Download gemma-3-12b-it
  • gguf: https://huggingface.co/unsloth/gemma-3-12b-it-GGUF/tree/main
• Download embeddings connectors
  • safetensors: https://huggingface.co/unsloth/LTX-2.3-GGUF/tree/main/text_encoders
• Download vae
  • safetensors: https://huggingface.co/unsloth/LTX-2.3-GGUF/tree/main/vae
• Download audio vae
  • safetensors: https://huggingface.co/unsloth/LTX-2.3-GGUF/tree/main/vae
• Download LTX spatial latent upscaler
  • safetensors: https://huggingface.co/Lightricks/LTX-2.3/resolve/main/ltx-2.3-spatial-upscaler-x2-1.1.safetensors

LTX-2.5

• Download LTX-2.5
  • safetensors: https://huggingface.co/Lightricks/LTX-2.5/tree/main/diffusion_models
  • gguf: https://huggingface.co/vantagewithai/LTX-2.5-GGUF/tree/main
• Download the text encoder. This is a Gemma 4 12B fine-tuned for LTX with the text projection bundled in, so no separate --embeddings-connectors file is needed. Google's stock Gemma 4 is not a substitute.
  • safetensors: https://huggingface.co/Lightricks/LTX-2.5/blob/main/text_encoders/gemma4-12b-with-proj-ltx-2.5-bf16.safetensors
• Download the video vae. Use the conv variant: ltx-2.5-video-vae-conv-bf16.safetensors. The default ltx-2.5-video-vae-bf16.safetensors is a diffusion decoder, which is not implemented here.
  • safetensors: https://huggingface.co/Lightricks/LTX-2.5/blob/main/vae/ltx-2.5-video-vae-conv-bf16.safetensors
• Download the audio vae
  • safetensors: https://huggingface.co/Lightricks/LTX-2.5/blob/main/vae/ltx-2.5-audio-vae-bf16.safetensors
• Download the LTX spatial latent upscaler
  • safetensors: https://huggingface.co/Lightricks/LTX-2.5/blob/main/latent_upscale_models/ltx-2.5-latent-spatial-upscaler-x2-bf16-1.0.safetensors

To run the text encoder quantized, convert it once with sd-cli:

.\bin\Release\sd-cli.exe -M convert -m ..\models\text_encoders\gemma4-12b-with-proj-ltx-2.5-bf16.safetensors --type q8_0 -o ..\models\text_encoders\gemma4-12b-with-proj-ltx-2.5-Q8_0.gguf

Examples

LTX-2.3 dev T2V

.\bin\Release\sd-cli.exe -M vid_gen --diffusion-model  ..\models\diffusion_models\ltx-2.3-22b-dev-UD-Q4_K_M.gguf --vae ..\models\vae\ltx-2.3-22b-dev_video_vae.safetensors --audio-vae ..\models\vae\ltx-2.3-22b-dev_audio_vae.safetensors --llm ..\models\text_encoders\gemma-3-12b-it-qat-UD-Q4_K_XL.gguf --embeddings-connectors ..\models\text_encoders\ltx-2.3-22b-dev_embeddings_connectors.safetensors  -p "a lovely cat" --cfg-scale 6.0 --sampling-method euler -v -n "worst quality, low quality, blurry, distorted, artifacts" -W 1280 -H 720 --diffusion-fa --offload-to-cpu --video-frames 33 --fps 24 -o t2v.webm

LTX-2.3 dev I2V

.\bin\Release\sd-cli.exe -M vid_gen --diffusion-model  ..\models\diffusion_models\ltx-2.3-22b-dev-UD-Q4_K_M.gguf --vae ..\models\vae\ltx-2.3-22b-dev_video_vae.safetensors --audio-vae ..\models\vae\ltx-2.3-22b-dev_audio_vae.safetensors --llm ..\models\text_encoders\gemma-3-12b-it-qat-UD-Q4_K_XL.gguf --embeddings-connectors ..\models\text_encoders\ltx-2.3-22b-dev_embeddings_connectors.safetensors  -p "a lovely cat" --cfg-scale 6.0 --sampling-method euler -v  -W 1280 -H 720 --diffusion-fa --offload-to-cpu --video-frames 33 -i ..\assets\ernie_image\turbo_example.png -o i2v.webm

LTX-2.3 dev FLF2V

.\bin\Release\sd-cli.exe -M vid_gen --diffusion-model  ..\models\diffusion_models\ltx-2.3-22b-dev-UD-Q4_K_M.gguf --vae ..\models\vae\ltx-2.3-22b-dev_video_vae.safetensors --audio-vae ..\models\vae\ltx-2.3-22b-dev_audio_vae.safetensors --llm ..\models\text_encoders\gemma-3-12b-it-qat-UD-Q4_K_XL.gguf --embeddings-connectors ..\models\text_encoders\ltx-2.3-22b-dev_embeddings_connectors.safetensors  -p "glass flower blossom" --cfg-scale 6.0 --sampling-method euler -v  -W 1280 -H 720 --diffusion-fa --offload-to-cpu --video-frames 33 --init-img ..\..\ComfyUI\input\start_image.png --end-img ..\..\ComfyUI\input\end_image.png -o flf2v.webm

LTX-2.3 spatial latent upscale

LTX spatial latent upscale runs a model-backed x2 latent upsampler between the low-resolution video pass and the high-resolution refine pass. -W and -H are the pre-upscale generation size; the spatial upsampler produces x2 latent dimensions.

Put ltx-2.3-spatial-upscaler-x2-1.1.safetensors under the directory passed to --hires-upscalers-dir, then use the model name without path or extension in --hires-upscaler.

.\bin\Release\sd-cli.exe -M vid_gen --diffusion-model  ..\models\diffusion_models\ltx-2.3-22b-dev-UD-Q4_K_M.gguf --vae ..\models\vae\ltx-2.3-22b-dev_video_vae.safetensors --audio-vae ..\models\vae\ltx-2.3-22b-dev_audio_vae.safetensors --llm ..\models\text_encoders\gemma-3-12b-it-qat-UD-Q4_K_XL.gguf --embeddings-connectors ..\models\text_encoders\ltx-2.3-22b-dev_embeddings_connectors.safetensors --hires-upscalers-dir ..\models\latent_upscale_models --hires-upscaler ltx-2.3-spatial-upscaler-x2-1.1 --hires --hires-steps 4 -p "a lovely cat" --cfg-scale 6.0 --sampling-method euler -v  -W 640 -H 360 --diffusion-fa --offload-to-cpu --video-frames 33 -i ..\assets\ernie_image\turbo_example.png -o hires_i2v.webm

By default, the hires refine pass uses the main sampler and scheduler, then trims the second-pass sigma schedule by --hires-denoising-strength (0.7 by default). To reproduce a ComfyUI-style explicit refine schedule, pass custom hires sigmas:

--hires-sigmas "0.85,0.725,0.421875,0.0"

LTX-2.5 dev T2V

.\bin\Release\sd-cli.exe -M vid_gen --diffusion-model ..\models\diffusion_models\ltx-2.5-22b-dev-transformer-Q8_0.gguf --vae ..\models\vae\ltx-2.5-video-vae-conv-bf16.safetensors --audio-vae ..\models\vae\ltx-2.5-audio-vae-bf16.safetensors --llm ..\models\text_encoders\gemma4-12b-with-proj-ltx-2.5-Q8_0.gguf -p "A wide aerial shot of a red vintage convertible driving along a coastal cliff road at sunset, waves crashing below" --cfg-scale 3.0 --sampling-method euler -v -n "worst quality, low quality, blurry, distorted, artifacts" -W 1280 -H 720 --diffusion-fa --offload-to-cpu --video-frames 121 --fps 24 -o t2v.webm

LTX-2.5 dev I2V

.\bin\Release\sd-cli.exe -M vid_gen --diffusion-model ..\models\diffusion_models\ltx-2.5-22b-dev-transformer-Q8_0.gguf --vae ..\models\vae\ltx-2.5-video-vae-conv-bf16.safetensors --audio-vae ..\models\vae\ltx-2.5-audio-vae-bf16.safetensors --llm ..\models\text_encoders\gemma4-12b-with-proj-ltx-2.5-Q8_0.gguf -p "a lovely cat blinking slowly, gentle camera push in" --cfg-scale 3.0 --sampling-method euler -v -W 1280 -H 720 --diffusion-fa --offload-to-cpu --video-frames 121 -i ..\assets\ernie_image\turbo_example.png -o i2v.webm

LTX-2.5 spatial latent upscale

Works exactly like the LTX-2.3 upscaler described below; put ltx-2.5-latent-spatial-upscaler-x2-bf16-1.0.safetensors under --hires-upscalers-dir and pass its name without path or extension to --hires-upscaler.

.\bin\Release\sd-cli.exe -M vid_gen --diffusion-model ..\models\diffusion_models\ltx-2.5-22b-dev-transformer-Q8_0.gguf --vae ..\models\vae\ltx-2.5-video-vae-conv-bf16.safetensors --audio-vae ..\models\vae\ltx-2.5-audio-vae-bf16.safetensors --llm ..\models\text_encoders\gemma4-12b-with-proj-ltx-2.5-Q8_0.gguf --hires-upscalers-dir ..\models\latent_upscale_models --hires-upscaler ltx-2.5-latent-spatial-upscaler-x2-bf16-1.0 --hires --hires-steps 6 -p "a lovely cat" --cfg-scale 3.0 --sampling-method euler -v -W 640 -H 360 --diffusion-fa --offload-to-cpu --video-frames 121 -o hires_t2v.webm

Not implemented

• The diffusion video decoder (ltx-2.5-video-vae-bf16.safetensors). Use the conv VAE.
• The temporal latent upscaler and the duration head (--auto-duration); pass --video-frames explicitly.