Photogrammetry
Definition
A technique that uses overlapping photographs to reconstruct three-dimensional geometry from two-dimensional images. In forensic engineering, photogrammetry and Structure-from-Motion (SfM) software allow a detailed spatial record of a scene or component to be built from standard camera photographs, providing a geometric record that survives even after the evidence itself has been moved or tested.
- Common software tools
- Agisoft Metashape, RealityCapture, Pix4D
- Primary forensic applications
- Scene reconstruction, vehicle damage analysis, skeletal trauma documentation, archaeological site recovery
- Technical approach
- Structure-from-Motion (SfM) converts overlapping photographs into 3D geometry using standard camera equipment
Common questions
What is photogrammetry used for in forensics?+
Photogrammetry creates detailed 3D models of crime scenes, vehicle damage, skeletal remains, and other evidence from overlapping 2D photographs. This produces a permanent digital record that experts can review later without needing the physical evidence present. It is especially valuable in forensic archaeology, where the 3D model captures exact positions of bones and artifacts before excavation disturbs them.
How does photogrammetry actually work?+
You take multiple photographs of a scene from different angles and positions. Software analyzes the overlapping details in these photos to mathematically calculate the 3D geometry and spatial relationships. The result is a scaled, three-dimensional reconstruction that preserves measurements and spatial accuracy.
What is the advantage of having a 3D photogrammetry record?+
It survives after evidence is moved, tested, or destroyed. A photogrammetry model stays accessible to any expert for review and analysis, making it useful when physical evidence degrades or is no longer available.
Related terms
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- Phosphate Survey
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- Photographic Triad
- The mandatory three-shot sequence for every piece of crime-scene evidence: overall (wide context), mid-range (relational to a fixed scene landmark), close-up (macro...
Explained in these topics
- Evidence Preservation and DocumentationA technique that uses overlapping photographs to reconstruct three-dimensional geometry from two-dimensional images. In forensic engineering, photogrammetry an...
- Forensic Archaeological Scene RecoveryThe generation of a scaled three-dimensional model from multiple overlapping photographs taken from different positions. Used in forensic archaeology (Agisoft...
- Forensic Photography: Types and ApplicationsReconstruction of a 3D scene from a structured stack of 2D photographs. Pix4D, Agisoft Metashape, RealityCapture. Used for scene reconstruction, vehicle damage...