How Realistic Is Threat Image Projection for X-ray Baggage Screening?
Abstract
:1. Introduction
2. Pre-Study
2.1. Method
2.1.1. Participants
2.1.2. Procedure
- Placement artifacts: The FTI is positioned such that it appears to penetrate an item in the baggage (e.g., the heel of a shoe).
- Alignment artifacts: The FTI is oriented such that it is poorly aligned with the content of the baggage. For example, the FTI is oriented at a 45° angle, while all other items are neatly packed and horizontally oriented. In some cases, the FTI can be oriented such that it appears to float (e.g., when an FTI bomb is oriented at a 45° angle away from a book or laptop lying flat).
- Distortion artifacts: This type of artifact refers to unrealistic distortion. It should be noted that X-ray images generally display a distorted image of the recorded items. The distortion depends on the location of an item in relation to the X-ray-beam source. The distortion of the FTI can appear unrealistic if it does not appropriately reflect the location in relation to the X-ray source.
- Color artifacts: The color of the FTI is unrealistic. For example, the color of an FTI gun looks different from the color of actual X-rays of guns.
- Size artifacts: The size of the FTI is unrealistic. The FTI is too small or too large.
- Resolution artifacts: The image resolution of the FTI differs from the image resolution of the other items in the TIP image.
- Edges artifacts: The edges of the FTI differ from the edges of the other items in the TIP image.
- Halo artifacts: There is a lightened area surrounding the FTI like a halo.
2.1.3. Results
2.1.4. Discussion
3. Main Study
3.1. Method
3.1.1. Participants
3.1.2. Materials
3.1.3. Procedure
3.1.4. Measures
3.1.5. Analyses
3.2. Results
3.3. Discussion
4. General Discussion
4.1. Prevalence of Artifacts and Unrealistic Scenarios in TIP Images
4.2. How to Reduce Artifacts and Unrealistic Scenarios
4.3. Limitations and Future Research
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Acknowledgments
Conflicts of Interest
References
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Characteristics | Ratings | Anchors |
---|---|---|
Artifact | ||
Artificial in general | The X-ray image looks unrealistic because the FTI looks artificial. | Totally disagree (1) Totally agree (7) |
Placement | The location of the FTI is unlikely. | “” |
Alignment | The alignment of the FTI seems artificial. | “” |
Other reasons why the FTI seems artificial … | ||
Artifact | ||
Color | … due to unrealistic color | “” |
Size | … due to unrealistic size | “” |
Resolution | … due to unrealistic resolution | “” |
Distortion | … due to unrealistic distortion | “” |
Edges | … due to unrealistic edges | “” |
Unrealistic Scenario | The TIP image looks unrealistic because the scenario is unrealistic. | “” |
IBF | ||
FTI view difficulty | Difficulty to recognize the threat item in the depicted orientation | Very easy (1) Very difficult (7) |
Superposition | Superposition of the FTI by other items | Very low (1) Very high (7) |
Bag complexity clutter | Clutter in the baggage | Very low (1) Very high (7) |
Bag complexity opacity | Proportion of the image that is opaque | Very small (1) Very large (7) |
Overall | FTI in Piece of Baggage | FTI on Loose Items in a Tray | |
---|---|---|---|
Placement Artifact | 17% | 3% | 37% |
Alignment Artifact | 15% | 6% | 25% |
Any Artifact 1 | 24% | 7% | 45% |
Unrealistic Scenario | 26% | 3% | 56% |
Any Artifact or Unrealistic Scenario | 34% | 8% | 65% |
Variable | M | SD | 1 | 2 | 3 | 4 | 5 | 6 |
---|---|---|---|---|---|---|---|---|
1. Placement Artifact | 2.13 | 0.88 | ||||||
2. Alignment Artifact | 2.84 | 0.98 | 0.64 ** | |||||
[0.57, 0.69] | ||||||||
3. Unrealistic Scenario | 2.66 | 0.89 | 0.81 ** | 0.69 ** | ||||
[0.77, 0.84] | [0.64, 0.74] | |||||||
4. FTI View Difficulty (Rated) | 2.98 | 1.28 | −0.37 ** | −0.48 ** | −0.53 ** | |||
[−0.46, −0.28] | [−0.56, −0.40] | [−0.60, −0.45] | ||||||
5. FTI View Difficulty (TIP-Reports) | 0.10 | 0.11 | −0.17 ** | −0.29 ** | −0.29 ** | 0.48 ** | ||
[−0.27, −0.07] | [−0.39, −0.20] | [−0.39, −0.20] | [0.39, 0.55] | |||||
6. Superposition (log) | 0.78 | 0.47 | −0.29 ** | −0.32 ** | −0.37 ** | 0.69 ** | 0.08 | |
[−0.38, −0.19] | [−0.41, −0.22] | [−0.45, −0.27] | [0.63, 0.74] | [−0.03, 0.18] | ||||
7. Bag Complexity (log) | 0.81 | 0.45 | −0.23 ** | −0.18 ** | −0.29 ** | 0.50 ** | −0.01 | 0.73 ** |
[−0.33, −0.13] | [−0.28, −0.08] | [−0.38, −0.19] | [0.42, 0.57] | [−0.11, 0.10] | [0.67, 0.77] | |||
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Riz à Porta, R.; Sterchi, Y.; Schwaninger, A. How Realistic Is Threat Image Projection for X-ray Baggage Screening? Sensors 2022, 22, 2220. https://doi.org/10.3390/s22062220
Riz à Porta R, Sterchi Y, Schwaninger A. How Realistic Is Threat Image Projection for X-ray Baggage Screening? Sensors. 2022; 22(6):2220. https://doi.org/10.3390/s22062220
Chicago/Turabian StyleRiz à Porta, Robin, Yanik Sterchi, and Adrian Schwaninger. 2022. "How Realistic Is Threat Image Projection for X-ray Baggage Screening?" Sensors 22, no. 6: 2220. https://doi.org/10.3390/s22062220
APA StyleRiz à Porta, R., Sterchi, Y., & Schwaninger, A. (2022). How Realistic Is Threat Image Projection for X-ray Baggage Screening? Sensors, 22(6), 2220. https://doi.org/10.3390/s22062220