What Is RTI?

Reflectance Transformation Imaging (RTI) is a computational photographic method that captures a subject’s surface shape and color and enables the interactive re-lighting of the subject from any direction in a software viewer, revealing details not visible with the naked eye. Learn more…

Need Some Help?

Let CHI experts advise you on your imaging challenge. CHI offers customized consulting services to both institutional and private clients, with special rates for nonprofit organizations. Projects of all sizes can be accommodated. Learn more…

Need Training?

CHI offers training in Reflectance Transformation Imaging (RTI) and photogrammetry. Learn more about these classes. You can also write to training@c-h-i.org.

Training by CHI

$50 suggested donation

Question? Ask on the CHI Forums

CHI offers a free discussion forums site where you can share your questions, insights, and issues as you work with Reflectance Transformation Imaging (RTI). Join the conversation!

RTI Workflow Materials

» Capture

  • Download the guide and the glossary
  • Watch the instructional videos

» RTI Highlight Capture Starter Kit

  • Order the RTI Starter Kit

» Process: RTIBuilder

  • Download the guide and example files
  • Download RTIBuilder

» View: RTIViewer

  • Download the guide and example files
  • Download RTIViewer

Process: RTIBuilder Download

RTI Process/Build  

RTIBuilder is a software interface to a set of tools that process your captured image set to produce the final RTI files. The RTIBuilder download includes the Hemispherical Harmonics (HSH) fitter to create .rti files.

Note: If you want to create Polynomial Texture Maps (PTMs), you must download the PTM Fitter software. See our user forums site for a Dropbox link to the PTMFitter download. In the RTIBuilder user guide, which you can download below, you will find installation instructions, including how to set up the PTM Fitter software: see the section entitled “Download the PTM Fitter plug-in.” RTIBuilder is written in the Java programming language, and it requires that you have Java version 6 or higher installed on your computer.

Download the Free and Open Source RTIBuilder Software, Sample Files, and User Guide

RTIBuilder Version 2.0.2 Apple/Mac logo Intel Macs with MacOS 10.5 or later required.
Note: On MacOs 10.9 and later you may get a misleading error message about RTIBuilder being damaged. See our post in the CHIForums about this problem.
RTIBuilder Version 2.0.2 Windows logo Win32
Reflectance Transformation Imaging: Guide to Highlight Image Processing Version 1.4 (PDF) Acrobat PDF logo This user guide describes all processing steps for creating RTI and PTM files, including the preparation of jpeg images prior to using the RTIBuilder application. This guide is NOT included in the software download and must be downloaded separately.
Glossary of Photographic and Technical Terms for RTI Acrobat PDF logo Version 1.0. Defines and explains terms related to the setup, capture, and processing of RTI images (308 KB)
Example Files icon for RTIBuilder example files fish_fossil-data-set_2000.zip (58 MB) Set of 36 jpeg images of a fish fossil at 2000 x 1334 pixel resolution (Recommended)

fish_fossil-data-set_1000.zip (18 MB) Set of 36 jpeg images of a fish fossil at 1000 x 667 pixel resolution (Smaller file size for those with limited bandwidth)
License GNU license icon RTIBuilder software is available under the Gnu General Public License version 3. If you wish to receive a copy of the source code, please send email to info@c-h-i.org.


Note: Please see the Guide to Highlight Image Capture (PDF) for more complete acknowledgments.

A team at the Universidade do Minho in Braga, Portugal, led by João Barbosa, were the primary developers of the RTIBuilder software.

The work was funded by Cultural Heritage Imaging and the Universidade do Minho. Cultural Heritage Imaging also provided software requirements, design advice, testing, general feedback, and documentation.

The 2.0.2 release of RTIBuilder includes the Hemispherical Harmonics (HSH) fitter. The HSHfitter was developed at the University of California, Santa Cruz, Computer Science Department in collaboration with Cultural Heritage Imaging, which provided funding for this work from the US Institute of Museum and Library Services (IMLS) National Leadership Grant Program (Award Number LG-25-06-010706). Tom Malzbender, formerly of Hewlett Packard Labs, also collaborated.

The Highlight RTI methodology was developed at Cultural Heritage Imaging by Mark Mudge, Marlin Lum and Carla Schroer with technical guidance from Tom Malzbender, formerly of Hewlett Packard Labs. The idea for Highlight RTI and its original execution came from a collaboration between Tom Malzbender, Mark Mudge, Marlin Lum, and Carla Schroer. Many others commented, tweaked, gave ideas and were generally helpful in the development of the capture methodology (described in detail in the guide Reflectance Transformation Imaging: Guide To Highlight Image Capture. It is impossible to name everyone who contributed, but we would especially like to acknowledge our Portuguese collaborators at the University of Minho: Alberto Proença, Luis Paulo Santos, and João Barbosa, as well as Professor James Davis at UC Santa Cruz.