This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Speed Analysis from Video: A Method for Determining a Range in the Calculations
ISSN: 0148-7191, e-ISSN: 2688-3627
Published April 06, 2021 by SAE International in United States
This content contains downloadable datasetsAnnotation ability available
Event: SAE WCX Digital Summit
This paper introduces a method for calculating vehicle speed and uncertainty range in speed from video footage. The method considers uncertainty in two areas; the uncertainty in locating the vehicle’s position and the uncertainty in time interval between them.
An abacus style timing light was built to determine the frame time and uncertainty of time between frames of three different cameras. The first camera had a constant frame rate, the second camera had minor frame rate variability and the third had more significant frame rate variability. Video of an instrumented vehicle traveling at different, but known, speeds was recorded by all three cameras. Photogrammetry was conducted to determine a best fit for the vehicle positions. Deviation from that best fit position that still produced an acceptable range was also explored. Video metadata reported by iNPUT-ACE and Mediainfo was incorporated into the study.
When photogrammetry was used to determine a vehicle’s position and speed from video recorded by a constant frame rate camera, the results closely matched the speeds reported by the instrumented vehicle being measured. This low uncertainty resulted from the constant frame rate eliminating error in time, and from low error in the vehicle’s position through photogrammetry. For the variable frame rate camera, uncertainty in speed was dependent on the time between frames analyzed as well as any uncertainty in position. Quantification of this uncertainty has value for the reconstructionist. Determining speed of the vehicle in the variable frame rate video could be improved by incorporating frame timing reported by iNPUT-ACE or through other video analysis techniques and software that measure precise time differences between each frame.
CitationBeauchamp, G., Pentecost, D., Koch, D., Hashemian, A. et al., "Speed Analysis from Video: A Method for Determining a Range in the Calculations," SAE Technical Paper 2021-01-0887, 2021, https://doi.org/10.4271/2021-01-0887.
Data Sets - Support Documents
|Unnamed Dataset 1|
|Unnamed Dataset 2|
|Unnamed Dataset 3|
|Unnamed Dataset 4|
|Unnamed Dataset 5|
|Unnamed Dataset 6|
- Coleman , C. , Tandy , D. , Colborn , J. , and Ault , N. Applying Camera Matching Methods to Laser Scanned Three Dimensional Scene Data with Comparisons to Other Methods SAE Technical Paper 2015-01-1416 2015 https://doi.org/10.4271/2015-01-1416
- Chou , C. , McCoy , R. , Fenton , S. , Neale , W. et al. Image Analysis of Rollover Crash Test Using Photogrammetry SAE Technical Paper 2006-01-0723 2006 https://doi.org/10.4271/2006-01-0723
- Fenton , S. , Neale , W. , Rose , N. , and Hughes , C. Determining Crash Data Using Camera-Matching Photogrammetric Technique SAE Technical Paper, 2001-01-3313 2001 https://doi.org/10.4271/2001-01-3313
- Neale , W. , Terpstra , T. , and Hashemian , A. 2017
- Neale , W. , Hessel , D. , and Koch , D. Determining Position and Speed through Pixel Tracking and 2D Coordinate Transformation in a 3D Environment SAE Technical Paper, 2016-010-1478 2016 https://doi.org/10.4271/2016-010-1478
- Neale , W. , Hessel , D. , and Terpstra , T. Photogrammetric Measurement Error Associated with Lens Distortion SAE Technical Paper 2011-01-0286 2011 https://doi.org/10.4271/2011-01-0286
- Rose , N.A. , Neale , W.T.C. , Fenton , S.J. , Hessel , D. et al. A Method to Quantify Vehicle Dynamics and Deformation for Vehicle Rollover Tests Using Camera Matching Video Analysis SAE Int. J. Passeng. Cars-Mech. Sys. 1 1 301 317 2008 https://doi.org/4271/2008-01-0350
- Rose , N. , Beauchamp , G. , and Asay , A. Rollover Accident Reconstruction Warrendale, PA SAE International 2019
- Taylor , J. An Introduction to Error Analysis, The Study of Uncertainties in Physical Measurements, Second Edition USA University Science Books 1982 13: 978-0-935702-75-0
- Terpstra , T. , Dickinson , J. , Hashemian , A. , and Fenton , S. Reconstruction of 3D Accident Sites Using USGS LiDAR, Aerial Images, and Photogrammetry SAE Technical Paper 2019-01-0423 2019 https://doi.org/10.4271/2019-01-0423
- Terpstra , T. , Miller , S. , and Hashemian , A. An Evaluation of Two Methodologies for Lens Distortion Removal when EXIF Data is Unavailable SAE Technical Paper 2017-01-1422 2017