Compression Artifact Analysis
JPEG Forensics
Analyzes JPEG compression artifacts to estimate quality levels and detect re-compression patterns that indicate image manipulation or AI generation.
Frequently Asked Questions
How is JPEG quality estimated?
By analyzing DCT coefficients in 8x8 blocks and comparing quantization patterns. Different JPEG quality settings produce distinctive coefficient distributions.
What are blocking artifacts?
JPEG compresses in 8x8 pixel blocks. Heavy compression creates visible block boundaries. AI output often lacks these natural JPEG artifacts or has unusual patterns.
Can you detect double compression?
Yes, re-saving a JPEG creates distinctive dual patterns in DCT histograms. This helps identify manipulated images that were saved multiple times.
Why do AI images have different compression patterns?
AI generates images at the pixel level without camera-like compression. When saved as JPEG, the compression patterns differ from camera-originated images.
Does PNG format bypass this detection?
PNG uses lossless compression, so this specific method doesn't apply. However, other detection methods work on PNG files effectively.
What is quantization noise analysis?
JPEG quantization introduces specific noise patterns. Camera sensors add their own noise on top. AI images lack this layered noise characteristic.
How does multiple re-saves affect detection?
Each re-save adds compression artifacts. Real photos typically show 1-2 compression generations; AI shared on social media may show many more.
What JPEG quality range is most informative?
Quality 70-90% provides the best balance. Higher quality has fewer artifacts to analyze; lower quality obscures original characteristics with heavy compression.
Is this effective against all AI models?
Yes, regardless of the AI model used, the output format determines compression patterns. All AI images show non-camera-like compression when saved as JPEG.
Why is the weight only 7%?
Compression patterns can be altered by format conversion and social media processing. This makes them less reliable than content-based methods, hence the lower weight.
관련 방법
ML 탐지
수백만 이미지로 훈련된 최첨단 Transformer 모델을 사용하여 실제 사진과 AI 생성 콘텐츠를 구별합니다.
PRNU 분석
Photo Response Non-Uniformity (PRNU) detects unique camera sensor fingerprints from manufacturing imperfections. AI images cannot replicate these authentic sensor signatures.
Frequency Analysis
Frequency domain analysis examines the distribution of high and low frequency components in an image. AI-generated images typically lack the natural high-frequency noise present in real photographs.
그래디언트 분석
Analyzes edge patterns and texture characteristics using Sobel, Canny, and Laplacian operators. AI images often have unnaturally smooth or uniform gradients.
노이즈 패턴
Real photographs contain unique noise patterns from camera sensors that vary across the image. AI-generated images have unnaturally uniform noise distribution.
메타데이터 분석
Image metadata contains valuable clues about its origin. We analyze EXIF data, software signatures, and other embedded information to identify AI generation tools.
GAN 지문
체커보드 패턴, 컬러 밴딩, 생성적 적대 신경망 고유의 스펙트럼 이상과 같은 GAN 특유 아티팩트를 탐지.
텍스처 분석
AI 생성 이미지에서 흔히 발견되는 텍스처 이상에 대한 Local Binary Pattern 분석.
Anatomy Detection
AI image generators often create anatomical errors that humans immediately recognize as wrong. We use computer vision to detect these telltale mistakes.
C2PA Verification
C2PA (Coalition for Content Provenance and Authenticity) is an industry standard for tracking the origin and history of digital content through cryptographic signatures.
Semantic Inconsistency Detection
Detects logical inconsistencies like incorrect shadows, impossible perspectives, distorted reflections, and violations of physical laws that AI often produces.
Human Biometric Analysis
Uses MediaPipe to analyze human anatomy for incorrect finger counts, asymmetric eyes, unnatural skin texture, and other anatomical anomalies common in AI-generated faces.
Lighting Physics Validation
Validates light source consistency, shadow direction physics, specular highlight accuracy, and color temperature uniformity across the image.
Edge Sharpness Analysis
Analyzes sharpness distribution across the image and validates depth-of-field consistency. AI often produces unnaturally uniform sharpness.
Statistical Pattern Analysis
Analyzes statistical properties including Shannon entropy, histogram patterns, and Benford's Law compliance to detect synthetic image characteristics.
Chromatic Aberration Analysis
Detects the absence of chromatic aberration (color fringing) that real camera lenses produce. AI images lack these optical artifacts.
Micro-Texture Analysis
Analyzes microscopic texture patterns for repetition, uniformity, and unnatural randomness that AI generators often exhibit.
Color Palette Analysis
Analyzes color distribution including saturation levels, color diversity, and white balance consistency. AI images often have oversaturated colors.
이미지 확인
All methods are combined using weighted scoring to produce a final verdict with confidence level.
지금 시도