Photogrammetry transformation matrix?
Posted: Fri Jun 19, 2009 10:17 am
The fundamental principle used by photogrammetry is that through "known" distances into and across a photograph, you can traingulate to determine "unknown" distances in a photograph.
Check out Northwestern and look for 'Perspective Grid for Photographic Mapping of Evidence' it touches on the topic.
Since then a plethora of papers have been written on photogrammetry.
GM at one point sold a program associated with the process related to SAE 86-1416 "Photogrammetic Analysis Using the Personal Computer" by Brelin, etc
There was a review of six different methods in SAE 940925 "Photogrammetry and Accident Reconstruction: Experimental Results" by Tumbus, etc. Available from SAE. http://www.sae.org. [http://www.sae.org/technical/papers/940925]
Since then a number of software vendors market these tools (photomodeler[http://www.photomodeler.com], pc-rect[http://pc-crash.com/product_pcrect.php], etc.)
Bottom line is if you have 4 reference points in a photo, go back to the Northwestern procedure which simply requires tracing paper and a ruler and creating a rectangle from the know dimensions and expanding or dividing that rectangle (carefully and accurately!) to determine the location your items of interest relative to the baseline measurements.
Check out Northwestern and look for 'Perspective Grid for Photographic Mapping of Evidence' it touches on the topic.
Since then a plethora of papers have been written on photogrammetry.
GM at one point sold a program associated with the process related to SAE 86-1416 "Photogrammetic Analysis Using the Personal Computer" by Brelin, etc
There was a review of six different methods in SAE 940925 "Photogrammetry and Accident Reconstruction: Experimental Results" by Tumbus, etc. Available from SAE. http://www.sae.org. [http://www.sae.org/technical/papers/940925]
Since then a number of software vendors market these tools (photomodeler[http://www.photomodeler.com], pc-rect[http://pc-crash.com/product_pcrect.php], etc.)
Bottom line is if you have 4 reference points in a photo, go back to the Northwestern procedure which simply requires tracing paper and a ruler and creating a rectangle from the know dimensions and expanding or dividing that rectangle (carefully and accurately!) to determine the location your items of interest relative to the baseline measurements.