ComfyUI Model Tools

Utility scripts for packaging models for ComfyUI.

Merge Safetensors

merge_safetensors.py: Merge all safetensors files in a directory into a single safetensors file. If duplicate keys exist, they are skipped with a warning:

python.exe merge_safetensors.py ".\source\folder\path" "target_file_path.safetensors"

Convert SeedVR2 to Safetensors

seedvr2_convert.py: Convert a ByteDance SeedVR2 .pth checkpoint into ComfyUI-loadable safetensors in fp16, fp8_e4m3fn, mxfp8, nvfp4, or int8. Each --job writes one precision; an optional PRECISION:OUT:SHA256 verifies the written file:

python seedvr2_convert.py --src seedvr2_ema_3b.pth --cond pos_emb.pt,neg_emb.pt \
    --job fp16:seedvr2_3b_fp16.safetensors \
    --job nvfp4:seedvr2_3b_nvfp4.safetensors

The mxfp8, nvfp4, and int8 modes require the comfy-kitchen package; the script exits with a message naming it if it is not installed.

Quantize to int8-convrot

Dry-run first (good idea to do this on a new architecture) — prints the plan, writes nothing

python quant_int8_convrot.py model_bf16.safetensors --dry-run

Quantize (defaults: absmax, min-gemm 256)

python quant_int8_convrot.py model_bf16.safetensors model_int8_convrot.safetensors

args

--dry-run — plan only (grouped quantize list + what's left behind, with reasons)
--w4a8 — int4 weights + codebook + fp8 group scales, int8 activations
--w6a8 — uniform int6 weights, ~3x lower weight error than W4A8 for 1.5x the bytes
--group-size N — columns per fp8 group scale for --w4a8/--w6a8 (default 16 / 32). Smaller groups track
    the weights more closely at cost of larger weights (8/N extra bits per weight), speed is unaffected.
--exclude RE / --include RE — regex overrides on layer base names
--min-gemm N — skip layers with min(N,K) < N (default 256)
--mseclip — MSE-optimal clip instead of absmax, usually lower weight error, experimental
--downcast-fp32 — shrink stray fp32 passthrough to the compute dtype
--warn-thresh F — warn on any quantized layer over F% relerr (default 2.0; 4.0 for W6A8, 10.0 for W4A8)
--verify-report PATH — dump the full per-layer (relerr, cos, gs) table