DeepShield: A Multimodal Deepfake Detection System Safeguarding Digital Content Authenticity

DeepShield is a multimodal deepfake detection system for images, videos, and audio. Built on EfficientNet-B0 and custom CNN models, it was trained on a dataset of over 170,000 samples, achieving excellent performance with an image detection accuracy of 97.77% and an audio detection accuracy of over 99%. The system uses a FastAPI backend, supporting real-time detection and large-scale deployment, aiming to safeguard the authenticity of digital content.

The rapid development of generative AI technology has led to an exponential growth in the quality and quantity of deepfake content (such as face-swapped videos and voice cloning), which is misused in scenarios like disinformation spread, online fraud, and privacy violations. Traditional manual review cannot meet the demand for processing massive content, so there is an urgent need for automated, high-precision deepfake detection technology.

Technical Architecture

• Image Detection: Based on EfficientNet-B0, it achieves efficient feature extraction through a compound scaling strategy, with processes including preprocessing, feature extraction, classification inference, and confidence calibration
• Video Detection: On top of image detection, it adds temporal consistency analysis, compression artifact detection, and facial action unit analysis
• Audio Detection: Uses a custom CNN, optimized for synthetic traces like spectral features, voiceprint anomalies, and breathing pauses

Training Strategy

• Dataset: Over 170,000 samples, covering real/fake content, diverse scenarios, and mainstream generation technologies
• Data augmentation: Geometric transformations, color jittering, noise injection, Mixup/CutMix, etc.
• Infrastructure: NVIDIA DGX B200 platform, supporting multi-GPU parallelism, mixed-precision training, and early stopping mechanism

Accuracy Metrics

Modality	Accuracy	Precision	Recall	F1 Score
Image	97.77%	97.5%	98.1%	97.8%
Video	96.2%	95.8%	96.5%	96.1%
Audio	99%+	99.1%	98.9%	99.0%

Robustness and Inference Performance

• Robustness: Supports stable detection under interference conditions like compression, resolution changes, and adversarial attacks
• Real-time performance: Single image response <100ms, 10-second video <500ms, 10-second audio <200ms, supporting hundreds of QPS concurrency

• Social Media: Real-time detection before upload, existing content scanning, hot event monitoring
• Financial Identity Verification: Remote account opening document verification, liveness detection, voice cloning attack prevention
• News Media: Manuscript review, traceability tracking, public education
• Forensic Investigation: Digital evidence verification, expert assistance, industry standard promotion

Current Challenges

The evolution of generation technology reduces fake traces, adversarial attack threats, adaptation to unknown fake types, and computational resource costs

Future Directions

• Technology: Multimodal fusion analysis, active defense (digital watermarking), federated learning, edge deployment, enhanced interpretability
• Ecosystem: Dataset sharing, standard formulation, industry collaboration, policy and regulation improvement

DeepShield is an important advancement in multimodal deepfake detection technology, providing a key technical defense line for the authenticity of digital content. However, technical detection alone is insufficient; it is necessary to combine laws and regulations, platform governance, and public education to build a comprehensive deepfake governance system.