HMM-based Attacks on Google's ReCAPTCHA with Continuous Visual and Audio Symbols.
Shotaro SanoTakuma OtsukaKatsutoshi ItoyamaHiroshi G. OkunoPublished in: J. Inf. Process. (2015)
Keyphrases
- visual information
- visual data
- cross modal
- hidden markov models
- search engine
- audio visual
- visual features
- multimedia
- visual speech
- countermeasures
- visual cues
- watermarking scheme
- multi modal
- signal processing
- low level
- visual perception
- web services
- audio signals
- security risks
- lifelog
- malicious attacks
- website
- video indexing and retrieval