ComfyUI-FeiFei

ComfyUI-FeiFei

FeiFei's ComfyUI custom nodes (CATEGORY = FeiFei): LLM-driven Prompt Director, prompt enhancing, image captioning, aspect-ratio sizing, style/character template assembly, watermark, format conversion, WebP save/load.

Example workflow

The screenshot above comes with the full workflow JSON: Workflow/ComfyUI-FeiFei.json. Download it and drag-and-drop onto the ComfyUI canvas to load (missing custom nodes will show as red boxes if you haven't installed this pack).

Install

cd ComfyUI/custom_nodes
git clone https://github.com/aifeifei798/ComfyUI-FeiFei.git
# Restart ComfyUI, nodes appear under the FeiFei category

Requirements: stock ComfyUI torch / numpy / Pillow plus openai>=1.40 (see requirements.txt). If openai is missing, LLM calls automatically fall back to the standard library — the pack still imports and runs.

Nodes

| Node | File | Notes | |---|---|---| | Prompt Director | prompt_director_node.py | Type a few minimal keywords (e.g. "cyberpunk, rainy night, red-haired girl"); an LLM director expands them into a ready-to-use shot. Outputs positive_prompt (subject + scene + mood + camera/lighting merged), negative_prompt, and aspect_ratio (clamped to the Aspect Ratio node's whitelist — convert that node's widget to input and connect it). model_style switches prompt dialect: Flux natural language / SDXL comma tags / Qwen-Image bilingual prose. Endpoint comes from config.json | | Prompt Enhancer | qwen_prompt_node.py | Prompt rewriting via OpenAI-compatible API (llama.cpp :8080 by default). Inputs: user_prompt / mode / temperature / thinking_mode. Outputs rewritten prompt + ratio + size + thinking. /v1/chat/completions with /completion fallback, T2I / I2I system prompts. Endpoint comes from config.json | | Image Captioner | image_caption_node.py | Upload image → vision model writes Chinese description + English prompt. Requires a vision model behind the API (e.g. Qwen-VL / MiniCPM-V); max_side caps upload size (default 1024). Endpoint comes from config.json | | Aspect Ratio (1024) | aspect_ratio_node.py | No more megapixel math: pick ratio + lock mode (Short Side / Fixed Width / Fixed Height) + base side (default 1024), outputs 16-aligned width/height straight into Empty Latent. Its aspect_ratio widget accepts a connected ratio string (e.g. from Prompt Director) after Convert to input | | Watermark | watermark_node.py | Three-line bottom-right watermark, per-line font size, white text with black stroke, cross-platform font lookup (FEIFEI_FONT_PATH first) | | Film Grain & Tone | film_grain_node.py | Physical film post-processing, pure torch with no external models. Sits after your sampler, before the watermark. Organic grain + halation + lens chromatic aberration + print curve + micro-contrast | | Image To RGB (Force 3-Channel) | image_to_rgb.py | Forces 3-channel RGB + contiguous(), tolerates NCHW / grayscale / RGBA, for picky downstream nodes (e.g. NVIDIA RTX VSR) | | Style Selector EX | style_selector_node_zh_ex.py | prompt1/2/3 text boxes + four extra input sockets prompt4~prompt7 (link-only, appended after the boxes) → character template (juese_data.py) → style template (style_data.py), optional random style. Add styles/characters by editing the two data files | | Save WebP (Timestamp) | ComfyUI_SaveWebP/save_webp_node.py | Timestamped WebP (millisecond + index, no overwrites). Prompt + seeds auto-saved to EXIF + sidecar .json (below); lossless, embed_metadata / save_json toggles | | Load WebP Info | same | Reads back prompt/seeds: sidecar JSON first, EXIF fallback. Outputs positive / negative / seeds / info_json |

Shared LLM helpers (_post_chat_completions, thinking-mode constants, JSON extraction, base-URL normalization) live in llm_common.py so the LLM nodes don't depend on each other.

Endpoint settings: config.json

Prompt Enhancer, Prompt Director and Image Captioner read api_base / api_key / model from config.json in this folder. None of them has those inputs in the node panel — edit the config file instead. The file is re-read on every run, so changes apply immediately with no ComfyUI restart.

{
  "api_base": "http://127.0.0.1:8080",
  "api_key": "",
  "model": "",
  "per_node": {
    "FeiFeiImageCaptioner": { "api_base": "", "api_key": "", "model": "" },
    "FeiFeiPromptDirector": { "api_base": "", "api_key": "", "model": "" },
    "QwenImagePromptEnhancer": { "api_base": "", "api_key": "", "model": "" }
  }
}

• Top-level keys set the shared endpoint. A per_node entry overrides it for that node only; an empty string inherits the top-level value. Image Captioner often needs its own host, since it requires a vision model.
• api_base accepts a host root (http://127.0.0.1:8080) or a full /v1 URL. Cloud endpoints (OpenAI / DeepSeek / Moonshot / any OpenAI-compatible server) work the same way.
• Leave api_key empty for local llama.cpp, which needs no key. Cloud APIs need a real key there, and need model set (leave it empty only for llama.cpp-style servers that ignore it).
• No environment variable is read anywhere in this pack — not OPENAI_API_KEY, not OPENAI_BASE_URL, not proxy variables. config.json is the single source of truth, so what the pack sends is entirely determined by that file and nothing else on the machine.
• Why not a node input: ComfyUI writes widget values verbatim into every saved workflow and into image metadata, and a workflow stores those values as a positional array with no field names — so a key typed into a panel would land on disk, travel with any shared workflow or exported image, and could not even be scrubbed afterwards. Keeping the key in config.json keeps it out of everything a workflow produces.

LLM access: openai SDK first, urllib fallback

• Requests go through the official openai Python SDK when installed (with retries and auth handled for you). If the SDK is missing or fails to initialize, the node falls back to standard-library urllib with an Authorization header — a broken proxy env or missing package never kills the pack.
• No environment variable is read and no LLM node has an api_key widget. The only source of a key is config.json, so no ambient credential on the machine can be handed to a host named by someone else's workflow.

thinking_mode (Prompt Enhancer + Captioner + Prompt Director)

| Mode | System prompt | enable_thinking | Measured (same prompt) | |---|---|---|---| | Ours (8-step) (default) | Full 8-step file / instruction box | false | ~1600 chars content | | Model native | Built-in minimal prompt (JSON keys only) | true | ~550 chars content | | Both | Full prompt / instruction box | true | For future Qwen3-class models |

If the server rejects enable_thinking with 400, the node retries once without it. Old workflows pick up the default mode, no changes needed.

Film Grain & Tone (physical film post-processing)

Takes the "too clean, too plastic" look off AI images. No external models, torch only, about 0.2s at 1024² and 10ms at 4K on CUDA.

The stages run in the order a real film does: lens (vignette / lateral chromatic aberration) → film base (halation) → print (S-curve / split tone / micro-contrast) → emulsion (grain). Grain goes last so the print curve can't crush it.

Sits between VAEDecode and Watermark.

Choosing: mode / film_type / preset / preset_gain

mode is a hard switch, not a blend. Preset and custom never mix.

| mode | Who drives the look | |---|---| | Preset (default) | The stock in preset decides every effect. All sliders are ignored; preset_gain sets how strong it is. | | Custom | The sliders decide everything. film_type, preset and preset_gain are ignored. |

There is deliberately no in-between state: with a per-parameter mix factor it is never clear whether a slider you moved actually did anything. The sliders stay visible in Preset mode because ComfyUI cannot hide widgets, so they simply have no effect there.

preset_gain scales the seven effect amounts (grain, halation, vignette, print curve, micro-contrast, split tone, colour fringing) together and leaves the stock's own character alone (grain size, shadow bias, glow threshold). So 0.5 is a half-strength Tri-X rather than half of Tri-X's parameters, and 0.0 leaves the image untouched.

film_type only groups the preset list. It applies no effect of its own.

preset only changes the film's character (grain size, tonal response, halation tint, lens falloff) and never applies a colour grade, so your image keeps its own colours, it just looks like it was shot on film.

If you change film_type without changing preset, the node falls back to the first stock of the new family, so switching families never silently appears to do nothing.

Widgets are ordered by how you use them: mode first, then film_type / preset / preset_gain as one group, then the five main sliders, then seed. The fine-tuning inputs sit in the optional section, grouped by pipeline stage.

preset_mix was replaced by mode and preset_gain, and the widgets were reordered, so a workflow saved before this version needs its film node re-picked once.

Every widget has a tooltip explaining what breaks at which value (e.g. grain_amount past 0.6 starts looking like TV snow).

| film_type | Stocks | |---|---| | Color Negative | Portra 160 / 400 / 800, Ektar 100 / 500, Gold 200 / 400, Fuji C200, Pro 400H | | Slide | Ektachrome E100, Fuji Provia 100F | | B&W Negative | Tri-X 400, HP5 Plus 400, FP4 Plus 125, TMax 100 / 400, Delta 100 / 3200, Acros 100 | | Cinema | CineStill 400D / 800T, Vision3 250D / 500T, Cine 50D, 500T Expired | | Special | Cinestack 800T, Push +2 Stops, Cross Process | | Other | Digital Clean (adds almost nothing, handy as an A/B baseline) |

Each stock only declares the traits that differ from a shared "normal negative" baseline, so tuning one film never shifts the others.

Main sliders

Read in Custom mode, ignored in Preset mode.

| Widget | Default | Notes | |---|---|---| | grain_amount | 0.25 | Grain strength. Default is about ±3.5/255; 1.0 is about ±14/255. Past that it reads as TV snow, not film | | grain_size | 1.0 | Clump size, scaled automatically from the 1024 short side, so 4K gets physically larger grain | | halation | 0.15 | Highlight glow. Push to 0.3–0.5 for a light-leak feel | | vignette | 0.12 | Corner falloff | | tone | 0.25 | Print S-curve strength, including a ~0.015 black lift |

The optional section adds grain_shadows (how far grain leans into the shadows), grain_chroma (0 = fully monochrome grain, 1 = independent per channel), halation_threshold, halation_radius, vignette_size, chroma_shift (in pixels of corner fringing on a 1024px image), micro_contrast (the single most effective slider against waxy AI skin), and split_tone.

Why the grain doesn't look like salt-and-pepper noise

Real silver halide grain is clumped, not independent per pixel. So the noise is generated on a low-resolution grid and bicubic-upscaled, with only 6% per-pixel detail mixed in, then weighted by luminance — strongest in the midtones, falling off fast in the highlights, tilting into the shadows per grain_shadows. That per-pixel detail ratio is the critical part: turn it up and it immediately degrades into digital noise.

Notes

• Grain below 1/255 is destroyed by 8-bit saving or VAEEncode quantization — don't drop grain_amount below 0.02
• seed is reproducible; each image in a batch gets independent grain (seed + index), so feeding a frame sequence will not flicker
• RGBA input processes RGB only and passes alpha through untouched; grayscale and 2-channel inputs work too

WebP metadata

• Save: full workflow prompt comes via hidden PROMPT; positive/negative resolved by tracing workflow links (falls back to order); seeds collected from seed / noise_seed. Summary → EXIF ImageDescription, full prompt + workflow → sidecar .json.
• Read: PIL.Image.open(p).getexif()[270], exiftool -ImageDescription xxx.webp, or the Load WebP Info node.
• Note: ComfyUI's native drag-to-restore only understands PNG; WebP EXIF is for archiving. Old/external images return empty strings + a note.

LLM backend requirements

• Prompt enhancing / Prompt Director: any text LLM behind an OpenAI-compatible API — local llama.cpp on :8080, or a cloud endpoint configured in config.json.
• Captioning: vision model behind the same API; leave model empty (llama.cpp) or set it (vLLM/Ollama-style servers).

License

See LICENSE.