Researchers at Cardiff University and American firm 3dMD have developed a 3D modelling system that collects 3D data on a patient’s face to gain a more detailed analysis than is possible by direct observation or video recordings.
The technology converts pictures from three cameras into a moving 3D model of a patient's head.
The team of clinicians and computer scientists believe the 3D model can be used to help surgeons perform customised surgery when it is combined with CT scans of the bone structure and MRI data on muscle shapes.
Professor David Marshall from Cardiff University’s computer science and informatics department told Techworld that the system draws on two video feeds at slightly different angles to create a 3D geometric model of a person’s face.
The feeds are positioned at slightly different angles and an algorithm is used to match points on each image frame to corresponding points on the other. A third feed is used to determine the visual texture of the face.
“The algorithms work by picking, at random, small patches in one camera and then searching for the corresponding and unique occurrence of the pattern in the other camera,” said Marshall. “Once the match is found, simple geometric triangulation gives the point. Repeat this around 30,000 to 40,000 times to sample the face geometry.”
The cameras projects dots onto the face in order to make it easier to match corresponding points. Earlier solutions used infra-red light to project the dots but the Cardiff team and 3dMD used the latest LED technology to replace this with pulses of visible light that produce a more accurate model than has previously been possible.
The technology could be used in future to develop a suite of software tools for dental analysis and more general computer science based applications, such as graphics and animation, said Marshall.
“We have long term plans to commercially develop the technology,” he said. “Currently the market is small as 3D dynamic systems but we expect this technology to expand greatly in the coming years and find new markets.”