Direct - Photogrammetry

Question 1

Were you asked to perform an analysis in this case?

Answer 1

Yes, VFAU was requested to estimate the height of the individual depicted in the captured video.

Question 2

Did you perform an analysis?

Answer 2

Yes, I performed a reverse projection photogrammetry examination.

Question 3

On what date did you do it?

Question 4

In this case, did you have any difficulty with the alignment of the camera used to capture the questioned video footage?

Answer 4

No, I did not.

Question 5

Did you reach conclusion upon completion of your analysis?

Question 6

What are the factors that you must consider when assessing imagery for Reverse Projection Photogrammtry?

Answer 6

I must consider several factors.
First, is the questioned individual visible from the ground to the top of their head or headwear.
Second, is there sufficient foreground and background information to put a camera into place?
Third, Is there sufficient resolution to give a meaningful result?
Fourth Is the questioned individual standing upright?

Question 7

What do you mean by “is there sufficient resolution to give a meaningful result”?

Answer 7

When you take a photograph, you are capturing a three-dimensional image, but the image is displaying it as two dimensional. Because of this, objects father from the camera are going to be appear smaller than objects closer to the camera. However, resolution is the number of pixels in the image. You can think of it like laying a piece of transparent graph paper, or a grid, over the image. Each square of the grid is the same size. The higher the resolution, the smaller those squares will be, the lower the resolution the larger the squares will be.
If a person isn’t represented by enough pixels, then we would be able to get a result that is narrow enough to be meaningful.
For example, let’s say a person in an image is represented by 10 pixels. For easy math, let’s say the person is 5 feet tall, or 60 inches. That means that each of the 10 pixels that presents that person is worth 6 inches. Since a pixel is the smallest unit of an, I would only be able to narrow the distance from the ground to the top of the head or headwear within 6 inches. Meaning, it would be between 5 feet and 5 1/2 feet.

Question 8

What was the results of your examination?

Answer 8

The vertical measurement from the group to the top of the questioned individual’s head was measured to be approximately 6 feet 6 inches.

Question 9

Can a person be identified through a height determination?

Answer 9

No. Height is a class characteristic only. Meaning it is an attribute that can be associated with a group of individuals, rather than one specific person. For example, I know several people who are six feet tall.
However, a height determination can be used to include or exclude an individual from a group or assist in showing a link between individuals depicted at different times at one, or multiple, locations.

Question 10

You stated your results as a range, why is that?

Answer 10

I state my results as a range because there are two measurable sources of uncertainty associated with reverse projection photogrammetry.

Question 11

Can you describe the measurable sources of uncertainty associated with reverse projection?

Answer 11

The first is resolution accuracy, which is a measure of how narrowly the examiner can define where the top of the head of the questioned individual is.
The second is positional accuracy, which is a measure of how exactly the height chart was placed in a 3D space, using the questioned, or evidence, image, which is 2D.

Question 12

What is done to help mitigate these sources of uncertainty with reverse projection?

Answer 12

First, I zoom in until I can see the individual pixels of the image when I am selecting the top of the head or headwear of the questioned individual.
Second, I place a person in the questioned individual’s feet when we are on location. I am able to do this once the overlay is achieved with alignment of the foreground and background fixed objects.

Question 13

Can you give an example, other than height, of a way reverse projection can be useful in investigatons?

Answer 13

Other ways that reverse projection can be useful in investigations is through speed determination, determining the length of an object, such as a gun, in an image, and also determining the location of an image captured.

Question 14

Where are you currently employed?

Answer 14

I am currently employed with the Operational Technology Division, or OTD, of the Federal Bureau of Investigation, or FBI.

Question 15

Where are you assigned within OTD?

Answer 15

I am currently assigned to the Video Forensic Analysis Unit, or VFAU.

Question 16

What does VFAU do?

Answer 16

VFAU is composed of two programs: The Field Audio Video Program, known as FAVP, and the Image Analysis Program, known as IAP.
FAVP supports law enforcement efforts by providing critical incident multimedia data intake as well as audio and video enhancement and redactions.
IAP conducts opinion based forensic examinations of anything depicted in imagery.

Question 17

Is VFAU Accredited?

Answer 17

Yes, VFAU is part of the Digital Evidence Laboratory within the Operational Technology Division and is accredited by the American National Standards Institute National Accreditation Board, or ANAB.

Question 18

Could you please tell us our job title?

Answer 18

My job series with the FBI is Physical Scientist and my official job title within OTD is Forensic Examiner/Photographic Technologist. However, another way to describe my job would be a Forensic Examiner of known and questioned photographic evidence.

Question 19

What does it mean to be accredited?

Answer 19

To be accredited means that our laboratory follows standards in regard to our facility, staff, policies, procedures, and quality assurance. Compliance to these standards is regularly assessed by this outside party to ensure we are meeting these standards and applying them properly.

Question 20

How long have you been employed as a Forensic Examiner/Photographic Technologist

Answer 20

Since February or 2025.

Question 21

Could you describe your official duties?

Answer 21

As a forensic examiner in the Image Analysis Program, I perform four different types of examinations.
The first is one to one comparison of a questioned image to a known image and includes things like facial comparison, clothing comparison, and vehicle comparison.
The second is authenticity in which I seek to determine if the images depict real people and events, and/or if a specific camera captured a particular image.
Third is information extraction or enhancement. This is generally done in combination with one of the other types of examination but includes increasing the contrast or resizing the image, as well as looking at the metadata for things like the date, time, and location of the image taken, and the camera information and settings.
Fourth is photogrammetry, which is the science of taking measurements through imagery and is the examination type that I performed in this case.

Question 22

To which professional organizations do you belong?

Answer 22

I am a member of the International Association for Identification, or IAI.

Question 23

What is your formal education?

Answer 23

I earned a Bachelor of Arts in Criminal Justice from American Military University.

Question 24

Can you tell us how your education background relates to your current job?

Answer 24

I generally consider my education foundational in that it gave me a sound scientific background and helped me understand concepts such as critical thinking, problem solving, and working within a laboratory. While I consider my knowledge of imaging science to come from my experience and training.

Question 25

Do you have any special training in Imaging Science?

Answer 25

During the course of my FBI training program, I have completed several commercial trainings, such as: Forensic Video Analysis and the Law offered by the Law Enforcement and Emergency Services Video Association International Facial Examination offered by the Face Center of Excellence at Ideal Innovations, Inc. and Forensic Image and Video Enhancement by Amped Software

Question 26

What FBI training have you had in conducting photographic examinations?

Answer 26

I am participating in a training program at the FBI that consists of assigned readings, formal classroom instruction, written tests, participating in external trainings, mock casework and working on current casework under the guidance of a senior qualified forensic examiner.

Question 27

How long has the FBI been conducting photogrammetric examinations?

Answer 27

FBI photogrammetric analysis has been offered in court testimony in local, state, and federal courts, dating back to the 1970s.

Question 28

What is photogrammetry?

Answer 28

Photogrammetry is the science of determining measurements from images.

Question 29

Is photogrammetry a new science?

Answer 29

No, it is not.

Question 30

During your training, have you received any special training in the area of photogrammetry?

Answer 30

As part of the FBI training program, I completed a module on photogrammetry which consisted of assigned readings, written tests, completing mock reverse projection examinations, and assisting senior qualified forensic examiners with on-site reverse projection examinations.

Question 31

What is reverse projection photogrammetry?

Answer 31

Reverse Projection Photogrammetry, known as RPP, is a form of photogrammetry in which the crime scene is recreated. It requires going to the place where the questioned image was created and duplicating the imaging conditions that captured the original scene in order to take a measurement.

Question 32

How long has the FBI been conducting reverse projection photogrammetry?

Answer 32

Since the early 1990s

Question 33

Approximately how many reverse projection photogrammetric examinations have you conducted in the course of your employment at the FBI?

Answer 33

Approximately 7

Question 34

Are there any other agencies that use reverse projection photogrammetry?

Answer 34

Yes, the Wisconsin State Forensic Laboratory, the Netherlands Forensic Institute, and the Target Forensic Laboratory.

Question 35

Have you ever testified in a judicial proceeding?

Answer 35

No, this is my first opportunity to testify as an expert witness.