IllusionIQ

Evaluating Multimodal LLMs on Optical Illusions – generation, benchmarking, and insights.

Spring 2025PythonPyTorchDiffusion ModelsHugging FaceOpenAI API+3 more

Overview

A CSE576 (NLP) course project exploring whether state-of-the-art multimodal LLMs can recognize and interpret optical illusions. We built a reproducible pipeline to generate 447 illusion pairs across six categories using diffusion models, then benchmarked GPT-4o, GPT-4.1, o4-mini, and Gemini 2.0 Flash with a standardized question set.

447
Illusion Pairs
6
Categories
4
Models Benchmarked
CSE524 (NLP)
Course

Illusion Categories

Color Hybrids

49

🌀

Flips

48

🌀

Jigsaw

35

🌀

Multi-Object Hybrids

49

🌀

Rotations

186

🌀

Text-Blend Hybrids

80

🌀

Sample Gallery

Flip anagram: giraffe ↔ penguin
Flip anagram: giraffe ↔ penguin
Rotation: mountain village ↔ horse
Rotation: mountain village ↔ horse
Jigsaw: forest fox ↔ mountain cabin
Jigsaw: forest fox ↔ mountain cabin
Text-blend: hidden word in cracked pavement
Text-blend: hidden word in cracked pavement
City ↔ Cow
City ↔ Cow

Benchmark Results

Correct mappings remain < 4% across models; high false-affirmation rates indicate overconfidence without precise transformation reasoning.

ModelTotal ImagesCorrect MappingsFalse AffirmationsQ1 Negatives
Gemini 2.0 Flash44712 (2.7%)410 (91.7%)25 (5.6%)
GPT-4o44711 (2.5%)412 (92.2%)24 (5.4%)
o4-mini44711 (2.5%)415 (92.9%)21 (4.7%)
GPT-4.144717 (3.8%)403 (90.2%)27 (6.0%)

Generation Pipeline

  • Visual Anagrams & Factorized Diffusion (DeepFloyd IF) for anagrams / hybrids
  • Illusion-Diffusion for text-blend hybrids
  • Prompt-pair batching, negative prompts, guidance & noise tuning
  • Manual curation and metadata for reproducibility

Evaluation Protocol

  • Paired views per illusion (canonical + transformed)
  • 5-question template probing ambiguity, category, and transformation mapping
  • Metrics: correct mappings, false affirmations, Q1 negatives