Backtracking a bit to mention/question one point regarding the FBI removing height, specifically, from the FBI poster:
Some suspect info removed from FBI poster on Delphi killings | wthr.com
"The Delphi Task Force requested the FBI to remove the physical descriptors listed on the flyer. Investigators do not want to discourage or stop the public from submitting a tip because the person does not specifically meet the height, weight, and age description. Investigators would like the public to focus on the photo of the man on the bridge, the voice recording, and second sketch that was released by law enforcement."
I understand what they’re saying, but I thought the height is a variable that is determined/calculated via a scientific method. I remember from the old Forensic Files, etc. they were able to ascertain a subject’s height, for example someone in Walmart surveillance footage, via a mathematical/calculative approach. Iirc, there’s a specific name for this and I can not remember what it is right now. But my point is, isn’t the height something that is definitive, based on evaluating distance, etc.? So why would they want tips on subjects who may not be this height?
Obviously there is more room for variance wrt age and weight, but is there actually room for error with the original height estimate? I’m not quite understanding how the height could vary in this instance and appreciate feedback on this.
Eta: A quick google of height determination as related to suspects in video footage reveals many results; this link appears to mention what I’m thinking about:
How Video Forensic Experts Determine Height in Images and Videos | ncavf.com
“Enhanced photo from a crime scene. NCAVF used advanced 3D rendering software to build a model of the crime scene, compare that model to frames from surveillance video, and determine the height of a suspect.
The science of measuring height in photographs (or from video frames) is called photogrammetry. NCAVF is able to utilize these forensic techniques. This process can only be done after some aspect of successful crime scene reconstruction. The four main methods of measuring height are:
- 3D Modeling of the Perpetrator,
- 3D Modeling of the Crime Scene,
- Reverse Projection Photogrammetry, and
- Single View Metrology (Vanishing Points).”
Eta2: “Photogrammetry !! That’s what I was thinking of!!! I thought this was an exact science, maybe it’s not? Furthermore, IF there could be a variance of say a few inches even, wouldn’t they at least be able to provide a range? Now they could get tips of someone who is, say 5’5”. Why would they open themselves up to this if there is no way that could be the man on the bridge?
Eta3: Even before the advancement of “3D” technology, I think the height of a perp is something that could be ascertained pretty easily even without all the fancy technology.
Eta4: More from the above link, there is a lot at that link, worth a read, imo:
“Three challenges are often faced while determining the height of a person in any type of surveillance imagery or videos:
- Camera and Lens Calibration,
- Lens Distortion, and
- Techniques used by criminals to manipulate appearance of height.”
Last edited: Apr 3, 2022