facok
724f5fa153
Experimentally validated combined mechanism: 1. Butterworth LPF erases HF spatial anchoring (composition sketch) 2. Random 4x4 DCT field applied after blur redistributes latent energy Push runs after cleanup in single post-cfg hook — ensures signal survives. Defaults: strength=0.5, n_periods=2, noise_type=pink.
4.4 KiB
ComfyUI-DiversityBoost
Restore composition diversity for distilled diffusion models. Training-free, single-step, zero model modification.
The Problem
Step-distilled models (FLUX2.[Klein], z-image-turbo, etc.) generate high-quality images in few steps, but suffer from composition collapse: different seeds produce nearly identical layouts. A portrait prompt always puts the subject dead-center; a landscape prompt always uses the same horizon line.
Root cause: distillation freezes the spatial distribution of token norms across seeds, locking the model into a single "average" composition regardless of the initial noise.
The Fix
DiversityBoost applies two mechanisms at step 0 only, via a single post-CFG hook:
- HF attenuation (Butterworth LPF) — erases the high-frequency spatial anchoring from the model's fully-committed prediction, producing a blurry "composition sketch"
- DCT composition push — applies a random low-frequency spatial field that redistributes energy across the latent, nudging the model toward different compositions
The model then freely reconstructs coherent details at subsequent steps, with per-seed noise driving different reconstruction paths.
Zero model modification. Zero training. One node.
How It Works
- Convert the model's step-0 prediction to raw latent space
- Butterworth LPF in frequency domain — attenuate high-frequency amplitude (6th-order, elliptical, resolution-independent)
- DCT spatial field — synthesize a random 4×4 low-frequency field (zero DC, pink noise weighted), normalize to unit std, scale by strength
- Multiplicative push —
blurred × (1 + field), clamped to prevent dead zones - Convert back
Step 0 only. The model's own attractor handles the rest.
Installation
cd ComfyUI/custom_nodes
git clone https://github.com/facok/ComfyUI-DiversityBoost.git
No extra dependencies — only requires PyTorch (ships with ComfyUI).
Usage
MODEL → [Diversity Boost] → MODEL → KSampler
- Add the Diversity Boost node (category:
sampling) - Connect your model to the input, output to KSampler
- Generate with different seeds — compositions will vary
Default settings work well. No tuning needed for most use cases.
Parameters
| Parameter | Default | Range | Description |
|---|---|---|---|
| strength | 0.5 | 0.0 – 2.0 | Composition push amplitude. 0 = cleanup only, 0.5 = moderate, 1.0 = strong. |
| clamp | 1.0 | 0.1 – 3.0 | Upper bound for the multiplicative scale factor. Scale is clamped to [0.1, 1+clamp]. Higher = allow stronger push. |
| noise_type | pink | pink / white / blue | Frequency spectrum of random DCT coefficients. Pink boosts low-freq composition modes (recommended). |
| n_periods | 2 | 1 – 10 | Butterworth cutoff — spatial periods to preserve. Lower = more HF erased = more diversity. |
| dc_preserve | 0.0 | 0.0 – 1.0 | DC amplitude preservation. 0 = max diversity (tone varies per seed). 1 = preserve original brightness. |
| energy_compensate | False | — | Rescale output RMS to match original. Off by default. |
n_periods Guide
n_periods sets the Butterworth -3dB point at FFT bin N. Frequencies above this are strongly attenuated.
| Value | Effect |
|---|---|
| 1 | Most aggressive — erases nearly all spatial structure including most DCT composition signal |
| 2 | Recommended — clean frequency gap between DCT composition modes (bin ~1.5) and object-scale details (bin ~5+) |
| 3 | Moderate — preserves more mid-frequency detail |
| 4+ | Mild — less HF erased, less diversity |
strength Guide
| Value | Effect |
|---|---|
| 0.0 | HF cleanup only (no composition push) |
| 0.3 | Subtle composition variation |
| 0.5 | Moderate (default, recommended) |
| 1.0 | Strong composition changes |
Tips
- Start with defaults — strength=0.5, n_periods=2, noise_type=pink is a safe baseline
- Want more diversity? Raise
strength. Keepn_periods=2— lowering to 1 kills most DCT composition signal - Want cleanup only? Set
strength=0— pure HF attenuation, no composition push - Compatible with other model patches (ControlNet, etc.) — operates on a different hook
Tested Models
| Model | Status |
|---|---|
| FLUX2.[Klein] 9B | Tested |
| z-image-turbo | Tested |
Feel free to report results with other distilled models.
License
MIT