OREANDA-NEWS. September 30, 2011. Kaspersky Lab, one of the leading developers of secure content and threat management solutions, announces that it has been granted a new anti-spam patent in the USA – No. 8023697 – which covers a system and method for identifying spam in rasterized images. The application was filed earlier this year, and the patent was granted on September 20, 2011.

Spam filters currently have little problem detecting spam text messages. That is why spammers often use stealth technology to hide the text of unwanted messages in images. Filtering graphical spam is far more difficult: before an anti-spam filter can establish whether the text in a message is spam, it must first detect the text in an image. The majority of methods used to detect text in images are based on machine recognition of images. Machine recognition, however, requires uniformity in terms of size, style and the arrangement of symbols. This restriction is exploited by spammers who intentionally distort and create ‘noise’ in images to make detection more difficult.

Kaspersky Lab’s technology protected by this new patent was designed to effectively detect text and spam objects in raster images. This approach provides high-speed detection and can recognize spam text in almost any language.

The newly patented technology is based on a method of identifying objects in a raster image and tracing the contours of identified objects. Objects in the image are identified by tracing contours around each object. Based on the traced contour a signature of each object is generated. Whether or not the image contains text is determined by a comparison of the discovered object signatures and known spam image signatures. The new system can also effectively detect text in an image and compare it to known spam templates contained in databases.

At present Kaspersky Lab technologies are protected by 43 Russian and 34 US patents, and has a further 32 and 47 patent applications in the two countries, respectively. A further 42 patent applications covering innovational technologies in the information security field are currently being examined by the Chinese and European patent offices.