The rapid advancement of image-to-text extraction systems and large language models (LLMs) poses new challenges for educational assessment by making assignment materials easy to transcribe and solve with minimal human effort. To address this problem, we present AIRRI (Artificial Intelligence Resilient Reading Interface), a framework for generating machine-resistant educational content, a dataset of higher-education assignments for evaluation, and an initial evaluation of the human readability of AIRRI machine-resistant text designs. AIRRI employs two categories of machine-resistance techniques. First, AIRRI applies image transformations including character spacing, word spacing, line spacing, character opacity variation, stripe overlays, and image noise. Second, AIRRI applies decision-based adversarial attacks: RayS, SurFree, and ADBA. We evaluate AIRRI against three image-to-text systems: Tesseract, EasyOCR, and the transformer-based GOT-OCR2 model. Our results show that AIRRI substantially degrades automated text extraction performance. AIRRI increased character error rates for EasyOCR (6.9% to 55.9%), Tesseract (2.3% to 100.0%), and GOT-OCR2 (30.7% to 48.1%). Word error rates increased for EasyOCR (24.9% to 96.7%) and Tesseract (10.7% to 100.0%). Among the evaluated decision-based attacks, ADBA consistently produced the largest degradation in image-to-text performance, while RayS and SurFree produced more moderate reductions. EasyOCR and Tesseract were generally more susceptible to both image-based and adversarial perturbations than the transformer-based GOT-OCR2 model. Our findings suggest that AIRRI can significantly reduce the reliability of image-to-text-to-LLM workflows, increasing the effort required for AI-assisted assignment completion.
Figures & tables
Figure 1: The AIRRI pipeline transforms instructor-provided assignments into machine-resistant rendered text while preserving human readability. Image-to-text and LLM systems can extract unprotected text, whereas AIRRI-protected text requires manual transcription.
Figure 2: Examples of AIRRI image-level perturbations; top left is the clean image. Intensity increases from Level 1 to Level 4.
Statistic
Value
Assignments
9
English Assignments
7
History Assignments
2
Total Words
4,364
Total Characters
25,282
Average Words
485
Table 1: Summary statistics for the educational assignment dataset for AIRRI’s evaluation. It has nine instructor-provided assignments from English and History courses with varying document lengths.
Model
Metric
HE Assignment
8-and-12
Clean
Prot.
Δ
Clean
Prot.
Δ
EasyOCR
CER (%)
6.94
55.95
+49.01
7.34
81.10
+73.76
WER (%)
24.86
96.67
+71.81
24.84
96.96
+72.12
Tesseract
CER (%)
2.26
100.00
+97.74
0.97
38.76
+37.79
WER (%)
10.65
100.00
+89.35
2.64
99.93
+97.29
GOT-OCR2
CER (%)
30.70
48.09
+17.39
0.83
90.42
+89.59
Table 2: Average extraction error rates for clean and AIRRI-protected documents. CER is Character Error Rate, and WER is Word Error Rate.
Perturbation
CER Δ (%)
WER Δ (%)
Jitter
6.27
17.04
Noise
3.96
17.17
Stripes
35.90
38.31
Table 3: Mean increase in image-to-text error rate (%) relative to clean images, averaged across all assignments, perturbation intensity levels, and extraction systems.
Protection
Model
LPS
LER
Clean
EasyOCR
94.4
5.6
Clean
Tesseract
94.4
5.6
Clean
GOT-OCR2
88.9
11.1
Clean
All
92.6
7.4
Protected
EasyOCR
77.8
22.2
Protected
Tesseract
0.0
100.0
Table 4: LLM Performance Score (LPS) and LLM Error Rate (LER) for clean and AIRRI-protected documents. Higher LER values indicate stronger resistance to downstream assignment completion.
Engine
Attack
ε
HE Assignment
8-and-12
CER (%)
WER (%)
CER (%)
WER (%)
EasyOCR
ADBA
8/255
6.38
28.54
5.48
27.05
16/255
5.82
28.23
5.05
25.62
32/255
5.65
28.33
4.80
23.49
64/255
8.07
34.00
6.46
28.80
Rays
8/255
6.78
29.31
6.99
29.77
Table 5: Full-composite CER/WER for adversarial perturbations.
Engine
Attack
ε
HE Assignment
8-and-12
CER (%)
WER (%)
CER (%)
WER (%)
EasyOCR
ADBA
8/255
4.36
23.96
3.95
21.61
16/255
4.34
23.99
3.81
20.81
32/255
6.31
29.87
4.85
24.23
64/255
49.83
80.07
44.81
76.14
Rays
8/255
4.58
25.15
4.42
23.29
Table 6: Target-region CER/WER for adversarial perturbations.
Appendix figures & tables2 assets
Supplementary material from the paper’s appendix.
Appendix
Perturbation
Level 1
Level 2
Level 3
Level 4
Opacity Jitter
25
50
75
100
Image Noise
25
50
75
100
Stripe Overlay
10
20
40
60
Appendix
Table 7: Parameter values corresponding to AIRRI perturbation levels. Level 0 represents the clean, unperturbed baseline.
Parameter
Value
Font Size
16 px
Character Spacing
3 px
Word Spacing
15 px
Line Spacing
Default
Stripe Intensity
20%
Stripe Angle
25∘
Appendix
Table 8: AIRRI configuration used for the full-pipeline evaluation.
Ubiquitous Knowledge Processing Lab (UKP Lab), Department of Computer Science, Technical University of Darmstadt · National Research Center for Applied Cybersecurity ATHENE, Germany · Zuse School ELIZA