Extensible format to enable ongoing innovation in 3D streaming and compression
HTML5DevConf– October 19th 2015 – San Francisco, CA –The Khronos Group, an open consortium of leading hardware and software companies, today announced that the glTF™ 1.0 (GL Transmission Format ) royalty-free specification for transmission and loading of 3D content has been finalized for Ratification and is immediately available for use by tools and application vendors. glTF is an efficient, interoperable asset delivery format that compresses the size of 3D scenes and models, and minimizes runtime processing by applications using WebGL™ and other APIs. glTF also defines a common publishing format for 3D content tools and services. More information on glTF specifications and activities is available at: https://www.khronos.org/gltf/.
“Amazing market opportunities are created when a standard emerges for efficiently transmitting and processing media data across the Internet. glTF will be as significant for 3D applications as JPEG and MP3 were for pictures and music,” said Neil Trevett, president of the Khronos Group and vice president at NVIDIA and chair of the Khronos 3D Formats Working Group. “glTF 1.0 provides baseline asset transport capabilities that every 3D application can use, and enables powerful extensibility for ongoing innovation in asset streaming and compression.”
Traditional 3D modeling formats, such as COLLADA™, are designed to exchange 3D assets within authoring workflows, but are not optimized for download or loading efficiency. Many applications convert assets to proprietary runtime formats, preventing tools from producing standardized models that can be consumed by any 3D application.
glTF defines a vendor- and runtime-neutral format that can be loaded and rendered with minimal processing. The format combines an easily parsable JSON scene and material description, which references binary geometry, textures and animations. glTF can be loaded efficiently into WebGL applications with minimal additional parsing and processing to create full hierarchical runtime scenes with nodes, meshes, cameras and animations.
“The WebGL and OpenGL™ APIs have brought 3D visualization to billions of consumers,” observed Tony Parisi, vice president of Platform Products at WEVR and co-editor of the glTF specification. “But until now there was no standardized way to get 3D data into those applications. glTF will enable a proliferation of 3D content for applications including entertainment, education, digital marketing, social media, and virtual reality, across all platforms.”
3D models and scenes may be used in a wide variety of applications, and so glTF is an extensible format to enable ongoing innovation around delivery, compression and streaming technologies for diverse use cases. Any company may define a vendor extension to glTF to meet their business needs, and Khronos provides a cooperative forum for widely used extensions to be standardized. Extensions available at the launch of glTF 1.0 include the ability to use binary scene descriptions and high precision rendering for geospatial applications. Extensions in development include sophisticated streaming of very large 3D CAD models from Fraunhofer IGD and advanced 3D mesh compression using 3DGC technology from the MPEG Consortium.
The glTF specification has been openly developed with the specification and source of multiple converters and loaders freely available on GitHub. Tools available at launch include offline and online convertors from COLLADA to glTF produced by Khronos, Analytical Graphics Inc. and Motorola Mobility, an FBX to glTF convertor in development by Autodesk, and loaders for leading WebGL engines including three.js, Microsoft’s Babylon.js, Cesium and X3DOM.
“In an industry characterized by a myriad of proprietary 3D formats, glTF addresses the need for standardization and sets the foundation for an ecosystem of OpenGL-based viewing and processing tools,” said Stefano Corazza, senior principal scientist at Adobe.
“glTF has some remarkable features that will make it simple for developers to include and run 3D digital assets in their web or mobile applications,” said Cyrille Fauvel, senior ADN Sparks manager at Autodesk.
“Unlocking 3D content from proprietary desktop applications to the cloud creates massive new opportunities for collaboration. Designers can share their work much earlier in the process, makers can show what their objects will look like before being printed, educators can incorporate interactive elements to the courses they produce, and much more. This future is so close we can feel it - the hardware is capable, the browsers are capable, now if only we could solve the content pipeline. Having an interoperable standard for tools manufacturers and engine developers to work against is a huge step - go glTF!,” said Ross McKegney , Platform @ Box.
“glTF will enable WebGL engines to reuse an ecosystem of asset pipeline tools, which will help both engines and tools move forward faster,” said Patrick Cozzi, principal graphics architect, Cesium.
“We are actively participating in the development of glTF because we strongly believe that declarative 3D and large model visualization will benefit from a standard for the efficient transmission of 3D resources,” said Johannes Behr, head of department Visual Computing System Technologies at Fraunhofer IGD.
“The conversion process of heavy elements such CAD and 3D sensor data is currently cumbersome due to a broken chain of legacy file formats and standardization gaps. Even though cloud computing and perceptual wearable hardware is capable of supporting interactive visual elements, 3D quality and visual trade-offs are almost inevitable when streaming to hands-free displays. glTF will democratize this process while removing obstacles for a number of once complex use cases. It will be especially useful for Augmented and Mixed Reality interoperability,” said Sam Murley, Research & Development Manager, DMI.
“It was obvious for the babylon.js team that glTF was a must have feature in order to integrate well within the 3D ecosystem,” said David Catuhe, principal program manager at Microsoft and author of babylon.js.
“Once the work began on glTF, the Babylon.js team quickly understood that glTF is set to become a highly significant standard,” said Julien Moreau-Mathis, Babylon.js team member, Microsoft.
“Defining a 3D graphics transmission model is challenging due to the extensive diversity of 3D graphics representations and use cases. Consequently, in contrast with images and video, the 3D ecosystem is being held back by a lack of a simple and universally efficient data representation. glTF has an important role by defining a foundation on which application specific compression and transmission components can be incrementally added. We are looking forward to glTF extensions to enable efficient MPEG compression technologies for 3D graphics to be widely deployed,” said Marius Preda of the MPEG Consortium.
“The Open Geospatial Consortium is currently developing a 3D Portrayal Service that enables interoperable visualization of distributed 3D geospatial data. glTF perfectly fits into this development as a data delivery format due to its compression and streaming capabilities,” said Volker Coors, chair 3D portrayal service standard working group, Open Geospatial Consortium.
“SRC is designed to exactly match Shape geometry in the Extensible 3D (X3D) International Specification, with proven HTML5 compatibility demonstrated by the open-source X3DOM project. The Web3D Consortium is eager to integrate SRC compression and stream-ability as part of X3D version 4 development. Web3D members are keen to continue partnered work with Khronos in this important area of Web interoperability,” Don Brutzman, X3D working group co-chair.
The Khronos Group is an industry consortium creating open standards to enable the authoring and acceleration of parallel computing, graphics, vision, sensor processing and dynamic media on a wide variety of platforms and devices. Khronos standards include Vulkan™, OpenGL®, OpenGL® ES, WebGL™, OpenCL™, SPIR™, SPIR-V™, SYCL™, WebCL™, OpenVX™, EGL™, COLLADA™, and glTF™. All Khronos members are enabled to contribute to the development of Khronos specifications, are empowered to vote at various stages before public deployment, and are able to accelerate the delivery of their cutting-edge media platforms and applications through early access to specification drafts and conformance tests. More information is available at www.khronos.org.
Khronos, Vulkan, DevU, SPIR, SPIR-V, SYCL, WebGL, WebCL, COLLADA, OpenKODE, OpenVG, OpenVX, EGL, glTF, OpenKCAM, StreamInput, OpenWF, OpenSL ES and OpenMAX are trademarks of the Khronos Group Inc. ASTC is a trademark of ARM Holdings PLC, OpenCL is a trademark of Apple Inc. and OpenGL is a registered trademark and the OpenGL ES and OpenGL SC logos are trademarks of Silicon Graphics International used under license by Khronos. All other product names, trademarks, and/or company names are used solely for identification and belong to their respective owners.