WAF-Based Chinese Character Recognition for Spam Image Filtering

We address the problem of filtering image spam, a kind of rapidly spread spam in which the text is embedded into images to defeat text-based spam filter. Particularly, we focus on image spam with Chinese text as “spam” which is a more challenging task. A popular way to detect image spam is by Optical character recognition (OCR) system, which detects and recognizes the embedded text, then followed ...