ComfyUI-STAR

ComfyUI custom nodes for STAR (Spatial-Temporal Augmentation with Text-to-Video Models for Real-World Video Super-Resolution) — a diffusion-based video upscaling model (ICCV 2025).

Features

• Diffusion-based 4x video super-resolution with temporal coherence
• Two model variants: light_deg.pt (light degradation) and heavy_deg.pt (heavy degradation)
• Auto-download: all models (UNet checkpoint, OpenCLIP text encoder, temporal VAE) download automatically on first use
• VRAM offloading: three modes to fit GPUs from 12GB to 40GB+
• Long video support: sliding-window chunking with 50% overlap
• Color correction: AdaIN and wavelet-based post-processing

Installation

ComfyUI Manager

Search for ComfyUI-STAR in ComfyUI Manager and install.

Manual

cd ComfyUI/custom_nodes
git clone --recursive https://github.com/ethanfel/Comfyui-STAR.git
cd Comfyui-STAR
pip install -r requirements.txt

The --recursive flag clones the STAR submodule. If you forgot it, run git submodule update --init afterwards.

Nodes

STAR Model Loader

Loads the STAR model components (UNet+ControlNet, OpenCLIP text encoder, temporal VAE).

Input	Description
model_name	light_deg.pt for mildly degraded video, heavy_deg.pt for heavily degraded video. Auto-downloaded from HuggingFace on first use.
precision	fp16 (recommended), bf16, or fp32.
offload	disabled (~39GB VRAM), model (~16GB — swaps components to CPU when idle), aggressive (~12GB — model offload + single-frame VAE decode).

STAR Video Super-Resolution

Runs the STAR diffusion pipeline on an image batch.

Input	Description
star_model	Connect from STAR Model Loader.
images	Input video frames (IMAGE batch).
upscale	Upscale factor (1–8, default 4).
steps	Denoising steps (1–100, default 15). Ignored in fast mode.
guide_scale	Classifier-free guidance scale (1–20, default 7.5).
prompt	Text prompt. Leave empty for STAR's built-in quality prompt.
solver_mode	fast (optimized 15-step schedule) or normal (uniform schedule).
max_chunk_len	Max frames per chunk (4–128, default 32). Lower = less VRAM for long videos.
seed	Random seed for reproducibility.
color_fix	adain (match color stats), wavelet (preserve low-frequency color), or none.
segment_size	Process video in segments of this many frames to reduce RAM usage (0–256, default 0). 0 = process all at once. Recommended: 16–32 for long videos. Segments overlap by 25% with linear crossfade blending.

VRAM Requirements

Offload Mode	Approximate VRAM	Notes
disabled	~39 GB	Fastest — everything on GPU
model	~16 GB	Components swap to CPU between stages
aggressive	~12 GB	Model offload + frame-by-frame VAE decode

Reducing max_chunk_len further lowers VRAM usage for long videos at the cost of slightly more processing time.

Model Weights

Models are stored in ComfyUI/models/star/ and auto-downloaded on first use:

Model	Use Case	Source
light_deg.pt	Low-res video from the web, mild compression	HuggingFace
heavy_deg.pt	Heavily compressed/degraded video	HuggingFace

The OpenCLIP text encoder and SVD temporal VAE are downloaded automatically by their respective libraries on first load.

Credits

• STAR by Rui Xie, Yinhong Liu et al. (Nanjing University) — ICCV 2025
• Based on I2VGen-XL and VEnhancer

License

This wrapper is MIT licensed. The STAR model weights follow their respective licenses (MIT for I2VGen-XL-based models).