CNN-Generated Images Are Surprisingly Easy to Spot… for Now

In this work we ask whether it is possible to create a "universal" detector for telling apart real images from these generated by a CNN, regardless of architecture or dataset used. To test this, we collect a dataset consisting of fake images generated by 11 different CNN-based image generator models, chosen to span the space of commonly used architectures today (ProGAN, StyleGAN, BigGAN, CycleGAN, StarGAN, GauGAN, DeepFakes, cascaded refinement networks, implicit maximum likelihood estimation, second-order attention super-resolution, seeing-in-the-dark). We demonstrate that, with careful pre- and post-processing and data augmentation, a standard image classifier trained on only one specific CNN generator (ProGAN) is able to generalize surprisingly well to unseen architectures, datasets, and training methods (including the just released StyleGAN2). Our findings suggest the intriguing possibility that today's CNN-generated images share some common systematic flaws, preventing them from achieving realistic image synthesis.

[1]  John Platt,et al.  Probabilistic Outputs for Support vector Machines and Comparisons to Regularized Likelihood Methods , 1999 .

[2]  Patrick Pérez,et al.  Poisson image editing , 2003, ACM Trans. Graph..

[3]  Hany Farid,et al.  Exposing digital forgeries by detecting traces of resampling , 2005, IEEE Transactions on Signal Processing.

[4]  Alexei A. Efros,et al.  Using Color Compatibility for Assessing Image Realism , 2007, 2007 IEEE 11th International Conference on Computer Vision.

[5]  Alex Zelinsky,et al.  Learning OpenCV---Computer Vision with the OpenCV Library (Bradski, G.R. et al.; 2008)[On the Shelf] , 2009, IEEE Robotics & Automation Magazine.

[6]  Alexei A. Efros,et al.  Unbiased look at dataset bias , 2011, CVPR 2011.

[7]  James F. O'Brien,et al.  Exposing photo manipulation with inconsistent reflections , 2012, TOGS.

[8]  Pietro Perona,et al.  Microsoft COCO: Common Objects in Context , 2014, ECCV.

[9]  Yinda Zhang,et al.  LSUN: Construction of a Large-scale Image Dataset using Deep Learning with Humans in the Loop , 2015, ArXiv.

[10]  Alexei A. Efros,et al.  Learning a Discriminative Model for the Perception of Realism in Composite Images , 2015, 2015 IEEE International Conference on Computer Vision (ICCV).

[11]  Jimmy Ba,et al.  Adam: A Method for Stochastic Optimization , 2014, ICLR.

[12]  Davide Cozzolino,et al.  Splicebuster: A new blind image splicing detector , 2015, 2015 IEEE International Workshop on Information Forensics and Security (WIFS).

[13]  Michael S. Bernstein,et al.  ImageNet Large Scale Visual Recognition Challenge , 2014, International Journal of Computer Vision.

[14]  Jian Sun,et al.  Deep Residual Learning for Image Recognition , 2015, 2016 IEEE Conference on Computer Vision and Pattern Recognition (CVPR).

[15]  Bolei Zhou,et al.  Learning Deep Features for Discriminative Localization , 2015, 2016 IEEE Conference on Computer Vision and Pattern Recognition (CVPR).

[16]  Li Fei-Fei,et al.  Perceptual Losses for Real-Time Style Transfer and Super-Resolution , 2016, ECCV.

[17]  Jiangqun Ni,et al.  A deep learning approach to detection of splicing and copy-move forgeries in images , 2016, 2016 IEEE International Workshop on Information Forensics and Security (WIFS).

[18]  Vincent Dumoulin,et al.  Deconvolution and Checkerboard Artifacts , 2016 .

[19]  H. Farid Photo Forensics , 2016 .

[20]  Vladlen Koltun,et al.  Photographic Image Synthesis with Cascaded Refinement Networks , 2017, 2017 IEEE International Conference on Computer Vision (ICCV).

[21]  Alexei A. Efros,et al.  Image-to-Image Translation with Conditional Adversarial Networks , 2016, 2017 IEEE Conference on Computer Vision and Pattern Recognition (CVPR).

[22]  Alexei A. Efros,et al.  Unpaired Image-to-Image Translation Using Cycle-Consistent Adversarial Networks , 2017, 2017 IEEE International Conference on Computer Vision (ICCV).

[23]  Hany Farid,et al.  Photo forensics from JPEG dimples , 2017, 2017 IEEE Workshop on Information Forensics and Security (WIFS).

[24]  Jia Xu,et al.  Learning to See in the Dark , 2018, 2018 IEEE/CVF Conference on Computer Vision and Pattern Recognition.

[25]  Jung-Woo Ha,et al.  StarGAN: Unified Generative Adversarial Networks for Multi-domain Image-to-Image Translation , 2017, 2018 IEEE/CVF Conference on Computer Vision and Pattern Recognition.

[26]  Davide Cozzolino,et al.  Detection of GAN-Generated Fake Images over Social Networks , 2018, 2018 IEEE Conference on Multimedia Information Processing and Retrieval (MIPR).

[27]  ForensicTransfer: Weakly-supervised Domain Adaptation for Forgery Detection , 2018, ArXiv.

[28]  Jaakko Lehtinen,et al.  Progressive Growing of GANs for Improved Quality, Stability, and Variation , 2017, ICLR.

[29]  Abhinav Gupta,et al.  Non-local Neural Networks , 2017, 2018 IEEE/CVF Conference on Computer Vision and Pattern Recognition.

[30]  Mario Fritz,et al.  Attributing Fake Images to GANs: Analyzing Fingerprints in Generated Images , 2018, ArXiv.

[31]  Andrew Owens,et al.  Fighting Fake News: Image Splice Detection via Learned Self-Consistency , 2018, ECCV.

[32]  Larry S. Davis,et al.  Learning Rich Features for Image Manipulation Detection , 2018, 2018 IEEE/CVF Conference on Computer Vision and Pattern Recognition.

[33]  Harshad Rai,et al.  Unpaired Image-to-Image Translation using Cycle-Consistent Adversarial Networks , 2018 .

[34]  Andrea Vedaldi,et al.  Deep Image Prior , 2017, International Journal of Computer Vision.

[35]  Felix Juefei-Xu,et al.  FakeSpotter: A Simple Baseline for Spotting AI-Synthesized Fake Faces , 2019, arXiv.org.

[36]  Xu Zhang,et al.  Detecting and Simulating Artifacts in GAN Fake Images , 2019, 2019 IEEE International Workshop on Information Forensics and Security (WIFS).

[37]  Jeff Donahue,et al.  Large Scale GAN Training for High Fidelity Natural Image Synthesis , 2018, ICLR.

[38]  Jitendra Malik,et al.  Diverse Image Synthesis From Semantic Layouts via Conditional IMLE , 2018, 2019 IEEE/CVF International Conference on Computer Vision (ICCV).

[39]  B. S. Manjunath,et al.  Detecting GAN generated Fake Images using Co-occurrence Matrices , 2019, Media Watermarking, Security, and Forensics.

[40]  Richard Zhang,et al.  Making Convolutional Networks Shift-Invariant Again , 2019, ICML.

[41]  Andrew Owens,et al.  Detecting Photoshopped Faces by Scripting Photoshop , 2019, 2019 IEEE/CVF International Conference on Computer Vision (ICCV).

[42]  Taesung Park,et al.  Semantic Image Synthesis With Spatially-Adaptive Normalization , 2019, 2019 IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR).

[43]  Bolei Zhou,et al.  Seeing What a GAN Cannot Generate , 2019, 2019 IEEE/CVF International Conference on Computer Vision (ICCV).

[44]  Han Zhang,et al.  Self-Attention Generative Adversarial Networks , 2018, ICML.

[45]  Yair Weiss,et al.  Why do deep convolutional networks generalize so poorly to small image transformations? , 2018, J. Mach. Learn. Res..

[46]  Andreas Rössler,et al.  FaceForensics++: Learning to Detect Manipulated Facial Images , 2019, 2019 IEEE/CVF International Conference on Computer Vision (ICCV).

[47]  Luisa Verdoliva,et al.  Do GANs Leave Artificial Fingerprints? , 2018, 2019 IEEE Conference on Multimedia Information Processing and Retrieval (MIPR).

[48]  Timo Aila,et al.  A Style-Based Generator Architecture for Generative Adversarial Networks , 2018, 2019 IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR).

[49]  Shu-Tao Xia,et al.  Second-Order Attention Network for Single Image Super-Resolution , 2019, 2019 IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR).

[50]  Tero Karras,et al.  Analyzing and Improving the Image Quality of StyleGAN , 2019, 2020 IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR).