Video Distortions, Visual Principles, Force Analysis

Looming Effects Related to Visual Principles and the Effects on Video Review and Examination 

Looming Effects Related to Visual Principles and the Effects on Video Review and Examination:

When combined with the distortive effects of a fish-eye lens, the visual principle of looming creates a unique set of challenges and considerations for video analysis. Here's a detailed look at how these factors interact and affect the interpretation of visual data:

1. Definition of Looming: Looming refers to the perceptual effect where an object appears to rapidly increase in size as it approaches the viewer, based on the number of visual angles being crossed specific to the direct approach, suggesting that it will imminently collide with them. This effect is critical in various fields, including psychology, for understanding how Officers perceive and react to approaching objects.Or, in the case of this report, how reviewers perceive information in a video with visual content that falls within the looming definition


2. Fish-Eye Lens Distortion: A fish-eye lens is an ultra-wide-angle lens that produces a spherical, convex, or hemispherical image. While it allows for a broader view—sometimes up to 180 degrees or more—it significantly distorts the image. Straight lines near the edges of the frame appear curved, and objects at the periphery are stretched and appear larger than those at the center. As discussed giving the appearance of being much further away than in reality

3. Impact on Video Analysis:
Altered Perception of Speed and Distance: The combination of looming and fish-eye lens distortion can significantly affect the perceived speed and distance of moving objects in a video. Objects moving toward the camera can appear to accelerate more rapidly than they actually are, due to the looming effect exacerbated by the distortion. This can lead to misjudgments in speed and timing, which are critical in applications like surveillance, sports analysis, and vehicle navigation systems.One major issue in the fisheye lens component is that the subject of focus at peak distance appears to be crossing visual angles at a slower speed. Because the subject at peak focal distance appears to be further away, it may in some cases appear that the subject is actually moving faster than they are. However, keeping in mind the officer perspective is that of the 50mm representation where the subject is actually much closer than they appear in the video, and looming, in reality, is affecting the officers' decisions.The subject is closing the real gap much faster than represented in the video – although the speed is a constant and doesn't actually change – see the video example.


Spatial Relationships: The distorted angles and spherical projection of a fish-eye lens can alter the apparent spatial relationship between objects. What might appear as a close proximity due to the lens' curvature could be a greater distance in reality. This distortion can complicate tasks that require precise measurements or understanding of spatial layouts, such as architectural videography or event analysis.


Size Estimation: Estimating the size of objects can be particularly challenging. The fish-eye lens exaggerates the size of objects closer to the edges of the frame, which, combined with the looming effect, can lead to significant overestimations of size and possibly misinterpretations of an object's importance or threat level.


Orientation and Navigation: For videos intended to aid in navigation or orientation within a space (such as officer-involved critical incidents), the combined effects of looming and lens distortion can disorient viewers' assessments. The exaggerated curvature of the environment and the altered speed perception may hinder the ability to judge distances accurately or navigate based on the video alone.


4. Compensations and Solutions: Addressing these challenges often requires post-processing correction of the fish-eye distortion, known as de-warping, to produce a rectilinear image. However, this correction can also modify the natural looming effect, necessitating careful calibration to preserve the intended visual cues. Most importantly, developing an understanding of the visual principles associated with the attentional process during these critical decision points is imperative, compensating for the altered visual principles in real-time analysis.

The visual principle of looming and the distortion effects of a fish-eye lens significantly impact video analysis, affecting the perception of time, distance, speed, motion, size, and spatial relationships. Overcoming these challenges requires an understanding of visual perceptions of those involved in the incident that is being reviewed in hindsight and how these same visual principles affect the reviewer of the evidence in hindsight. Although there are sophisticated correction techniques and analytical models to ensure accurate interpretation of visual data, remember the core of a successful review is to understand how these principles affect the human being involved, and the human being performing the post-incident review.

Authored by Sgt. Jamie Borden (Ret)

Founder, Critical Incident Review, (CIR)

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Thursday, 18 April 2024

The CIR Team has logged thousands of hours of continued and focused education in the field of Human Behavioral Sciences as it relates to law enforcement and has also logged thousands of hours of documented instruction time with multiple law enforcement entities as instructors, lecturers and authors.