在現代社會之中，網路新聞、社群媒體以及各式的論壇已經成為我們生活之中不可或缺的一部分。也因此，如何辨別網路消息的真實性已經成為現代人相當重要的課題。過去，報章媒體講究有圖為證，圖片可以作為一篇報導的重要證明。但如今，隨著深度學習、生成對抗網路等技術的成熟，網路上也充斥著各式經過偽造的圖片。
生成對抗網路為一種非監督式學習的方法，透過讓兩個神經網路相互競爭對抗的方式來進行學習。生成對抗網路是由一個生成網路及一個辨別網路所組成，生成網路輸出的結果需要盡量接近真實樣本，而辨別網路則需要將生成網路所產生的虛假樣本從真實樣本中分辨出來。透過兩個網路不斷地相互競爭對抗、調整，從而產生人眼也無法區別、以假亂真的圖片。
本篇論文中，講述透過捲積神經網路、特徵萃取，以及透過遷移學習的方式來設計並訓練一個模型來對生成對抗網路所產生的偽造圖片進行辨識。相較於過去針對特定目標的訓練，透過遷移學習的方式可以大幅地降低訓練所需要的時間及運算成本，亦能獲得不錯的辨識度。

In this thesis, we study the detection of the authenticity of images generated by generative adversarial networks through cnn, feature extraction, and transfer learning. The problem of class imbalance is solved by data augmentation. Transfer learning is used to design and train a model that can be used to identify fake pictures. The time and computational cost required for training can be significantly reduced compared to traditional training methods, and good performance can be obtained.

Abstract
Contents
List of Figures--------------------3
List of Tables---------------------4
1 Introduction---------------------5
2 Generative Adversarial Networks--7
3 Performance Measure of GAN------13
4 Detection of Fake Images--------17
Conclusion------------------------36
Bibliography----------------------37

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