(478.21) A Workflow for Digitizing Anatomical Specimens by Combining Photogrammetry and 3D Scanning

Poster Board Number: C79
Introduction: AAA has separate poster presentation times for odd and even posters.
Odd poster #s – 10:15 am – 11:15 am
Even poster #s – 11:15 am – 12:15 pm

Ishan Dixit (University of British Columbia), Connor Dunne (University of British Columbia), Curtis Logan (University of British Columbia), Monika Fejtek (University of British Columbia), Paige Blumer (University of British Columbia,), Ratthamnoon Prakitpong (University of British Columbia), Claudia Krebs (University of British Columbia)

The 3D visualization of anatomical specimens relies on two main technologies: 3D laser surface scanning and photogrammetry (PGM). While 3D laser scanning provides the most accurate 3D model, photogrammetry provides the best, photorealistic surface texture. Typically, a specimen would be assessed to see which technology is best to capture it - in this study we set out to investigate  whether it is feasible to combine both methods, incorporating the advantages of both. Artec Space Spider scanner was used to capture accurate geometry of specimens and create a mesh with high polygon count and topological accuracy in Artec Studio 15, and Reality Capture was used to capture photographs around the specimen at regular 5 degree increments until the entire surface was captured to produce a high-resolution textured mesh. The meshes were combined in Artec Studio 15 by matching their geometric centers in 3D space and ensuring that all polygons are precisely overlapped - even a minor amount of deviation would result in blurry reprojection of texture. This is followed by mapping and reprojecting the PGM texture on the 3D scanned mesh (now aligned and scaled) in Reality Capture and cleaning up the produced texture map in Adobe Photoshop to ensure that any artifacts are cleaned up. Through this combination, models that gather ‘best of both worlds’ qualities from 3D scanning and photogrammetry - laser accurate geometry and photorealism. We determined that 3D scanning is sufficient for specimens with simple texture, and photogrammetry is effective for specimens with complex texture and simple geometry; the combination method shines where great detail and high resolution texture is required to meet the learning objectives, such as organs and musculoskeletal specimens and other specimens with key topological details and colorations. Gathering both PGM and 3D scanning data allows for error correction, especially when performed in collaboration with a content expert and a 3D artist. Availability of these methods to produce photorealistic and accurate scans of specimens lends to accessibility of high quality online anatomy educational materials for students. This technology may also be useful in museum settings and to scan rare collections where to date a single method was not able to capture the complexity of the specimens .