What does 3-d imaging use to capture a digital map of an artifact
To capture a digital map of an artifact, 3D imaging typically uses a combination of techniques such as photogrammetry and laser scanning. Here's a step-by-step explanation of how these methods work:
1. Photogrammetry: This technique involves taking multiple high-resolution photographs of the artifact from different angles. The key is to capture as much detail as possible. To get accurate measurements, it's essential to have clear, well-lit photographs.
2. Image Processing: Once the photographs are taken, specialized software is used to process them. This software identifies common points in multiple photos and calculates the artifact's shape and dimensions based on the differences in perspective. By analyzing the relationship between these points in each image, a 3D model is generated.
3. Laser Scanning: Another method used for capturing 3D images of artifacts is laser scanning. This technique involves projecting laser beams onto the object from multiple directions and measuring the time it takes for the laser to bounce back. By calculating the distance to each point on the surface, a 3D point cloud is generated.
4. Point Cloud Processing: The point cloud obtained from laser scanning is further processed using specialized software. This processing includes filtering out noise and refining the data to create a more accurate representation of the artifact's shape and surface.
5. Mesh Creation: After obtaining the 3D point cloud, it is converted into a mesh, which is a surface composed of interconnected triangles or polygons. This mesh represents the digital map of the artifact, and it allows for visualization and manipulation in 3D software.
6. Texture Mapping: To enhance the visual appearance of the 3D model, texture mapping is performed. This involves projecting the original photographs taken during photogrammetry onto the surface of the model. The texture is aligned and warped to fit the model's geometry accurately.
Overall, 3D imaging combines the techniques of photogrammetry and laser scanning to capture an artifact's digital map. This process allows for accurate 3D representation and detailed analysis of the artifact without physical contact or potential damage.