We are independent & ad-supported. We may earn a commission for purchases made through our links.
Advertiser Disclosure
Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.
How We Make Money
We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently of our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What Is Photometric Stereo?

By Eugene P.
Updated May 16, 2024
Our promise to you
EasyTechJunkie is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At EasyTechJunkie, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject-matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

In computer graphics and, more specifically, computer vision applications, photometric stereo is the process of creating a three-dimensional (3D) model or representation of a two-dimensional (2D) image based on the way the objects in the image reflect or refract light. When a photometric stereo algorithm is applied to an object, there must be more than one source image available for analysis. For each of the source images to be used, the object generally should appear in a static position, while the light source is moved to reveal different aspects of the surface of the object. Simple methods of photometric stereo imaging must know the location of the lights in relation to the object, and they work the best when the object is made from a single material so the highlights and shadows can be predictably measured. Much more advanced algorithms and techniques do not require as much information in advance and can make several assumptions, or even interpolate surfaces, to complete a partially obstructed image.

The basic concept of photometric stereo involves taking several images of an object with the light source in each image moved around the object while the object remains in the same location. By measuring exactly how the shadows and highlights fall on the surface of the object in each image, the surface normals — the direction a surface faces — can be calculated. After compiling information on the normals of the measurable areas of an object across a series of 2D images, a 3D model of the object can be constructed.

Factors such as the depth of the shadows and intensity of the highlights help to determine the varying heights of the surface topography. Objects that have a glossy surface are the easiest to measure with photometric stereo, while objects that are made from a material with more subtle shadows, such as soft fabric, can be more difficult. An object that has a highly reflective surface, such as polished chrome, can present some problems without proper image adjustments, because the reflections can give false results. The algorithms work best when there is only a single light source and no projected shadows, as opposed to an area light, multiple light sources or a light that is shining through a window or other opening.

There are several uses for photometric stereo techniques. In real-time computer vision processing, it can be used to determine the depth of objects within a scene. It also can be used to create accurate 3D models of objects in photographs for historical, archival or analytical purposes.

EasyTechJunkie is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.

Related Articles

Discussion Comments
EasyTechJunkie, in your inbox

Our latest articles, guides, and more, delivered daily.

EasyTechJunkie, in your inbox

Our latest articles, guides, and more, delivered daily.