Diff-CAPTCHA: An Image-based CAPTCHA with Security Enhanced by Denoising Diffusion Model. (arXiv:2308.08367v1 [cs.CR])

To enhance the security of text CAPTCHAs, various methods have been employed,
such as adding the interference lines on the text, randomly distorting the
characters, and overlapping multiple characters. These methods partly increase
the difficulty of automated segmentation and recognition attacks. However,
facing the rapid development of the end-to-end breaking algorithms, their
security has been greatly weakened. The diffusion model is a novel image
generation model that can generate the text images with deep fusion of
characters and background images. …

attacks automated captcha captchas characters development facing image interference rapid recognition security segmentation text