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Studies of Internet filtering, network interference, and other technologies and practices that impact freedom of expression online. 

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“未阅先焚” 2: 微信如何实现实时审查用户对话中的敏感图片

本报告延续上一篇针对微信朋友圈图片过滤技术的研究,分析微信如何在聊天功能中实现实时图片过滤。微信是中国腾讯控股有限公司旗下的即时通讯应用,目前是中国最受欢迎的聊天软件之一,也是全球排名第四的最流行聊天软件。朋友圈是微信上最常用的功能之一,其中图片是用户最期望看到的内容分享形式。

(Can’t) Picture This 2: An Analysis of WeChat’s Realtime Image Filtering in Chats

In this work, we study how Tencent implements image filtering on WeChat. We found that Tencent implements realtime, automatic censorship of chat images on WeChat based on what text is in an image and based on an image’s visual similarity to those on a blacklist. Tencent facilitates this realtime filtering by maintaining a hash index of MD5 hashes of sensitive image files.

The Dangerous Effects of Unregulated Commercial Spyware

In recent days, United Nations Special Rapporteurs have released two revelatory reports that demonstrate the dangerous effects of unchecked technology in the hands of autocrats: one relating to the proliferation and abuse of surveillance software and one that investigates the murder of Washington Post journalist Jamal Khashoggi. Both reports highlight the danger of unaccountable and unregulated surveillance technology sold to countries with egregious human rights records.

被灭声的周年纪念:中国直播软件审查香港六四纪念及本土社运

今年是中国1989年天安门民主运动的30周年纪念。当年,学生自发举行一系列游行示威,呼吁实施民主改革,中共领导人则选择使用武力镇压运动。中国红十字会称有2700名民众在武力镇压中身亡,但有不少研究机构指出死伤人数远不止这个。在2014年解密的一份美国政府机密文件显示,中国内部统计的死亡人数达10,454人。