ComfyUI_EU_AI_Label

Label AI-generated images directly in your ComfyUI workflow with the official EU icon and machine-readable metadata, as required by Art. 50 EU AI Act (in force August 2, 2026).

Inspired by the browser tool KI-Label Studio, this node pack brings the same functionality into ComfyUI as the last step of every image generation:

Node	Purpose
EU AI Label (Visible)	Burns a visible label into the image: official EU AI icon, text, text + icon, or your own logo
EU AI Label (Metadata Writer & Save)	Writes machine-readable XMP metadata (IPTC DigitalSourceType etc.) and saves the file itself
EU AI Label (Metadata Check)	Inspects any image file: XMP, EXIF, IPTC — and detects embedded C2PA manifests

Installation

Via ComfyUI Manager (recommended)

Search for ComfyUI_EU_AI_Label in ComfyUI Manager and click Install, then restart ComfyUI.

Via comfy-cli

comfy node install eu_ai_label

Manual installation

cd ComfyUI/custom_nodes
git clone https://github.com/a-und-b/ComfyUI_EU_AI_Label.git
pip install -r ComfyUI_EU_AI_Label/requirements.txt   # Pillow + numpy, usually already present

Restart ComfyUI. The nodes appear under the category EU AI Label. Works with both the legacy renderer and Nodes 2.0.

An example workflow is included: example_workflows/eu-ai-label-example.json

Caution

Do not chain a regular SaveImage node after the Metadata Writer. ComfyUI image tensors cannot carry file metadata, and SaveImage writes its own metadata. Your AI labeling metadata would be lost! The Metadata Writer & Save node is a save node: it writes the file (with metadata) to your output/ folder itself. No SaveImage needed.

Node reference

EU AI Label (Visible)

Batch-capable. Composites the label with high-quality LANCZOS scaling, preserving the icon's aspect ratio.

• Label Type:
  EU Icon | Text | Text + EU Icon | Custom Logo (via the optional Custom Logo image input)
• EU Icon Variant:
  AI (base) | AI generated | AI modified (the three official EU icons)
• Color:
  black | white (the official 50 %-opacity variants are covered by the opacity slider)
• Custom Text:
  Default AI generated (bundled DejaVu Sans font, free license)
• Size (%):
  Label width in % of image width (default 7)
• Margin (%):
  Distance to the edge in % of image width (default 3)
• Opacity (%):
  1–100 % (default 100)
• Position:
  9-point grid, default bottom right

EU AI Label (Metadata Writer & Save)

• Digital Source Type:
  IPTC DigitalSourceType, the machine-readable AI marker that Google and others read:
  • trainedAlgorithmicMedia: fully AI-generated
  • compositeWithTrainedAlgorithmicMedia: AI-edited / composite
  • algorithmicMedia: algorithmic without AI training
  • none: do not set
• Description:
  (dc:description), Creator Tool (xmp:CreatorTool), Credit (photoshop:Credit)
• Custom XMP Fields:
  One key=value per line; known prefixes (dc:, xmp:, photoshop:, Iptc4xmpExt:) map to their namespaces, everything else goes into a package-specific namespace
• Embed Workflow:
  Embeds the ComfyUI workflow/prompt like SaveImage does. Privacy note: your prompts and node settings end up inside the image file. Default on; PNG files remain drag-&-drop-restorable in ComfyUI, WebP via EXIF.
• Format:
  PNG | JPEG | WebP, Quality (JPEG/WebP), Filename Prefix/Filename Suffix (default _ai-labeled)
• Output File Path (STRING)
  The saved file path(s), one per line — wire it into the Check node for an immediate round-trip verification.

Note

The XMP packet is generated as RDF/XML and embedded natively via Pillow (PNG: iTXt XML:com.adobe.xmp, JPEG: APP1 segment, WebP: XMP chunk). We deliberately avoid python-xmp-toolkit (needs the exempi C library) and pyexiv2 (binary wheels, platform issues) — zero extra dependencies, runs everywhere ComfyUI runs. No network access at runtime.

EU AI Label (Metadata Check)

This node shows if there already is AI labeling in a file. Input is a file path (tensors carry no metadata; relative paths resolve against the ComfyUI output folder. Or wire the Writer's File Path output straight in). Outputs a human-readable report and a JSON string; reads XMP (incl. DigitalSourceType), EXIF, IPTC-IIM and detects C2PA manifests (JPEG APP11/JUMBF, PNG caBX, WebP C2PA chunk). Detection only — signature verification and C2PA signing are out of scope (signing requires a certificate; planned as v2, see comfyui_c2pa_signer in the meantime).

Icon & font licenses

• The EU AI icons are the official icons published by the European Commission (June 2026). They are free to use, no attribution required. The original SVG sources ship under assets/icons/svg-source/; the PNGs the nodes actually load (assets/icons/*.png) are pre-rendered from these SVGs at 900px height via rsvg-convert, so the node runtime stays Pillow-only (no SVG-rendering dependency, which would drag in a native library like cairo and complicate Windows installs).
• Bundled font: DejaVu Sans (free license, see assets/fonts/LICENSE-DejaVu.txt).

Legal disclaimer

This tool does not constitute legal advice. Using the EU icons is voluntary; the obligation to label AI-generated or AI-manipulated content ("deep fakes" in the broad sense) under Art. 50 EU AI Act remains with you as the user/provider. Whether and how specific content must be labeled depends on your individual case.

Acknowledgements

• uncanny minds GmbH
  The creators of KI-Label Studio, the browser tool this node pack's feature set is modeled on.
• comfyui_c2pa_signer by mikecaronna
  Reference architecture for ComfyUI content-credential nodes, including the SaveImage-metadata pitfall this repo also documents.
• DejaVu Fonts project (based on Bitstream Vera, designed by Jim Lyles/Bitstream, Inc.)
  Bundled DejaVuSans.ttf, see assets/fonts/LICENSE-DejaVu.txt.
• European Commission
  Official EU AI-labeling icons, bundled under assets/icons/.