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OpenEXR Library

Professional OpenEXR support for VFX and HDR pipelines. Load EXR files and inspect their structure, display individual parts or manually-assembled channels as tone-mapped images, and save images or channel data back to EXR.

Installation

In the editor, open Manage → Library Management, click Add Library, and paste:

https://github.com/griptape-ai/griptape-nodes-library-openexr

Or via the CLI:

gtn libraries download https://github.com/griptape-ai/griptape-nodes-library-openexr

See the Libraries guide for general install, update, and troubleshooting help.

Nodes

Node Description
Load EXR Loads an EXR file and exposes its full structure (parts, channels, header attributes) as typed outputs — header-only by default, so it's fast even on large multi-part renders
Display EXR Part Renders an EXR part to an 8-bit sRGB/RGBA PNG with exposure and tone mapping (or OCIO color management)
Display EXR Channel Combines 1–4 individual EXR channels into an 8-bit display image, with optional alpha compositing over a background
Save EXR Saves a single-part EXR from an 8-bit image or from EXR channel artifacts, with compression, pixel type, and header metadata controls

Quick start

Load EXR → Display EXR Part → (image output)
         ↘ Display EXR Channel (assemble R/G/B/A from any parts or files)
  1. Add a Load EXR node and point file_path at a .exr file. The node scans the header and populates dynamic Parts and Channels groups.
  2. Wire a part output into Display EXR Part (or individual channels into Display EXR Channel) to get a tone-mapped PNG you can preview in the canvas or feed to other image nodes.
  3. Use Save EXR to write images or channel data back out as EXR.

OpenColorIO integration

The display nodes support two color modes:

  • basic — local exposure + tone mapping (filmic or linear).
  • ocio — a connected OCIOColorParamsArtifact (from the OpenColorIO Library) drives an OCIO display-view transform.

When the OpenColorIO Library is installed, the display nodes default to ocio mode automatically; otherwise they default to basic. The OCIO dependency is optional — everything works without it.

Library settings

Settings live in the engine configuration under the openexr category.

Setting Default Description
openexr.header_only true When true, Load EXR reads only the file header (fast). Set to false to read accurate per-channel pixel types at the cost of loading pixel data into memory.
openexr.viewer_executable "" Full path to an external HDR viewer executable (e.g. /usr/bin/djv, or a Nuke binary). When empty, the OS default file association is used.
openexr.viewer_args "" Additional command-line arguments passed to the viewer before the file path, e.g. --hdr --linear. Parsed with shell-style quoting rules.

Every node has an Open in external viewer button that opens the source EXR in the configured viewer (or the OS default). The viewer is launched fire-and-forget — clicking the button never blocks the canvas.

Support

Found a bug or have a feature request? Open an issue.