RISMEDIA, July 7, 2010—Soon after a recent glossary posting in RealTown’s “TourTalk” group, a question was sent in from one of our friends at another virtual tour company asking about the difference between 2D and 3D stitching.
This company has been and continues to be a leader in the virtual tour industry, so I thought that if they have questions about this, most other virtual tour enthusiasts probably do as well.
That said, the topic of this TourTalk article will endeavor to explain these differences in a clear and concise manner. To do this, I have asked Justin Furmage, CEO of Property Panorama, to chime in (as it was Justin who explained the difference to me in the first place).
Image stitching (the process of combining multiple photographic images with overlapping fields of view to produce a segmented panorama or image) has continually evolved since its introduction in the late 1970s.
Image stitching found its beginnings in a DARPA-funded project, with the creation of the technology that is now found in Google Street View and other similar technologies. In the mid 1990s, image stitching started to go mainstream, as it became more widely used by many commercial entities, especially in the real estate and travel industries.
During this time, a host of innovative companies, such as PhotoVista and bamboo.com, for example, began making stitching software commercially available, thereby empowering real estate agents with the tools necessary to create their own virtual tours.
Anyone with an adequate amount of computer “know-how,” proper training and moderate photography skills could now create virtual tours and post them to the Internet. The stitching technologies employed in these solutions use a stitching technology referred to as 2D-Stitching.
With 2D-Stitching technologies, great care must be taken when capturing the overlapping photographs that will be used. The person taking the photographs must either use a tripod, or meticulously pivot around the camera, being careful to keep the camera in the exact position between shots as it would be if a tripod were being used. If this is not done correctly, the resulting (stitched together) panorama will be quite flawed, leaving the person who took the photos to choose between returning to the location to take new photographs or using flawed, distorted images in their tours.
3D-Stitching is the latest advancement in stitching technologies and has advanced the field significantly by eliminating most of the photo-taking requirements associated with 2D-Stitching. Rather than simply moving the images in the series back-and-forth horizontally to find the best match, as is done with 2D-Stitching, in 3D-Stitching, all photographs in the series are moved in all directions, and also skewed, rotated, warped, resampled and moved in all possible locations, three dimensionally to find a perfect match between the images being stitched.
This eliminates the requirement that the person taking the photographs use a tripod, keep the camera in a fixed position, overlap any specific or pre-determined amount, keep the camera level, keep the same exposure between photographs and a host of other requirements inherent with 2D-Stitching technologies. In fact, 3D-Stitching technology can seamlessly stitch photographs that were taken while the person taking the photos is walking around the room, provided the photos overlap any amount at all.
Due to the greatly reduced requirements regarding photo-taking, 3D-Stitching technology is rapidly empowering more and more individuals to incorporate panoramic virtual tours into their arsenal of marketing tools. Real estate agents who previously thought they simply did not have (or did not have the time to acquire) the photography skills necessary to create high-quality virtual tours of their properties are making virtual tours with a degree of quality that previously would have been attainable only by hiring a professional photographer.
Mike Barnett is CIO at PropertyPanorama.com and can be reached at TourTalk@MikeBarnett.com.
