2023 2023-01-0618
Validation of the Arnold Render for Creation of Physically Correct Lighting Models
Vega, H., Suway, J.
SAE Technical Paper
- Visibility and lighting
Digital and spatial forensics
Forensically accurate media
What can be depicted in photographs of a night scene depends on the amount of light captured, which varies with camera settings. Without careful calibration, those setting choices can produce misleading images that exaggerate how visible a pedestrian in the frame appears.
An uncalibrated nighttime image makes objects substantially easier or harder to detect than they were on-scene. We use a scientific approach to produce scene-accurate stills, video, and animation, using the equivalent-contrast method our engineers developed and published.
Our imagery has been challenged by opposing counsel many times and has never been excluded from a courtroom.
Scope
What this covers
Deliverables
- Calibrated night scene still photography
- Calibrated video re-creations
- Physically based renders and animation
- Luminance maps of the scene as depicted
Method
- Camera calibration for luminance estimation
- Equivalent-contrast verification of the depiction
- Render engine validation against photometric measurement
- Documentation sufficient to reproduce the result
Peer-reviewed research
Published work behind this practice area
Authored by our engineers and peer-reviewed by external experts.
2022 2022-01-0802
A More Robust Method for Digital Video Camera Calibration for Luminance Estimation
Suway, J., Suway, S.
SAE Technical Paper
- Visibility and lighting
2021 2021-01-0853
Systematic Degradation of Retroreflective Materials for Testing and Research
Dinakar, S., Suway, J., Muttart, J., et al.
SAE Technical Paper
- Visibility and lighting
- Testing and instrumentation
2020 2020-01-0567
Simulation of Retroreflective Materials in a Physically Based Rendering (PBR) Engine
Cornetto, A., Suway, J.
SAE Technical Paper
- Visibility and lighting
2020 2020-01-0570
Quantifying Retroreflective Materials Using Digital Imagery
Suway, J., Cornetto, A.
SAE Technical Paper
- Visibility and lighting
Who does this work
Engineers on this practice area
Jeffrey Suway
PE, ACTAR
Visibility and conspicuity, human factors, and accident reconstruction
- Night visibility and conspicuity
- Lighting issues
- Human factors
- Accident reconstruction
27 publications
Henry V. Vega
PE, ACTAR
Accident reconstruction and audio analysis
- Accident reconstruction, commercial and passenger vehicles
- Audio analysis and speed determination
- Photogrammetry, digital mapping, and video analysis
- UAS scene capture and 3D simulation
6 publications
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