openimageio

OpenImageIO (OIIO) is a toolset for reading, writing, and manipulating image files of any format relevant to VFX and animation, exposed through a format-agnostic API designed for feature film production scale and robustness. Its primary audience is VFX studios and developers of renderers, compositors, viewers, and other image-related pipeline software. The project provides ImageInput and ImageOutput APIs that abstract file reading and writing so applications need not know format details or even which formats are available. Format support is implemented as runtime-discoverable plugins, covering TIFF, JPEG/JFIF, JPEG XL, OpenEXR, PNG, HDR/RGBE, ICO, BMP, Targa, JPEG-2000, RMan Zfile, FITS, DDS, Softimage PIC, PNM, DPX, Cineon, IFF, OpenVDB, Ptex, Photoshop PSD, Wavefront RLA, SGI, WebP, GIF, DICOM, HEIF/HEIC/AVIF, many RAW camera formats, and various movie formats readable as individual frames. Command-line tools built on these classes include oiiotool for format conversion and image processing, iinfo for printing image details, iconvert for converting formats, data types or metadata, idiff for comparing images, igrep for searching metadata, and iv as an image viewer. Because they share the same plugin layer, they work with any supported format. Additional components include ImageCache, which manages a transparent cache to access very large image collections efficiently with limited runtime memory; TextureSystem, offering filtered MIP-map texture lookups on top of ImageCache and used in commercial renderers; ImageBuf and ImageBufAlgo for storing and manipulating whole images in memory with common image processing operations; and Python bindings for the major APIs. The project is part of the Academy Software Foundation under the Linux Foundation. Original code uses the Apache-2.0 license and documentation uses CC-BY-4.0; a relicensing effort moved over 99.86% of code lines from BSD-3-clause to Apache-2.0. Documentation, quick-start guides, build instructions, architecture notes, contribution guidelines, an AI policy, roadmap and release process are available in the repository and at docs.openimageio.org. Community support runs through the oiio-dev mailing list, ASWF Slack, GitHub issues, and biweekly technical steering committee meetings.