LTX2 Sampling Preview Override(LTX2SamplingPreviewOverride)

Description

Overrides the LTX2 preview sampling preview function. This is a temporary measure until previews are natively supported in ComfyUI core. Use this node to enable or customize preview generation during LTX2 sampling, allowing you to control the frame rate and optionally upscale the preview latents for higher quality.

Inputs

• model (MODEL, required)
  The model to add the preview override to. The node wraps the model so that previews are generated during sampling.

• preview_rate (INT, required)
  Default: 8 | Min: 1 | Max: 60 | Step: 1
  Controls how often preview frames are generated during sampling. Higher values produce fewer previews (slower update rate), while lower values produce more frequent updates. For example, a rate of 8 means a preview is generated every 8 sampling steps.

• latent_upscale_model (LATENTUPSCALEMODEL, optional)
  An optional upscale model to use for generating higher resolution previews. If provided, the latent previews will be upscaled before passing to the VAE, resulting in sharper and more detailed preview images.

• vae (VAE, optional)
  The VAE model used for normalizing the latents before feeding them into the upscale model. This input is required if latent_upscale_model is provided. It ensures the latents are in the correct format for the upscaling process.

Outputs

• MODEL
  The same model with the preview override patched into it. Pass this model into any LTX2 sampling node to benefit from the customized preview behavior.

Usage Notes

• This node is specifically designed for the LTX2 architecture and should be placed before the sampling node in your workflow.
• If you do not need upscaled previews, leave latent_upscale_model and vae unconnected. The previews will be generated at the standard resolution using the primary VAE.
• The preview_rate value is relative to sampling steps; a lower number increases preview frequency but may slow down sampling due to additional VAE decodes.
• The node is part of the KJNodes/ltxv category in ComfyUI. It is a temporary workaround until preview functionality is integrated into ComfyUI's core.