Editing Email spam (section)

===Image spam===
{{Main|Image spam}}

[[Image spam]], or image-based spam,<ref name="Image Based spam name">Giorgio Fumera, Ignazio Pillai, Fabio Roli,{{cite journal|url=http://jmlr.csail.mit.edu/papers/v7/fumera06a.html|title=Spam filtering based on the analysis of text information embedded into images|journal=Journal of Machine Learning Research|year=2006|volume=7|issue=98|pages=2699–2720|last1=Fumera|first1=Giorgio|access-date=2013-03-19|archive-date=2015-02-21|archive-url=https://web.archive.org/web/20150221103301/http://jmlr.csail.mit.edu/papers/v7/fumera06a.html|url-status=live}} Journal of Machine Learning Research (special issue on Machine Learning in Computer Security), vol. 7, pp. 2699-2720, 12/2006.</ref><ref name="Image Based spam name 2">Battista Biggio, Giorgio Fumera, Ignazio Pillai, Fabio Roli,{{cite journal|title=A survey and experimental evaluation of image spam filtering techniques| doi=10.1016/j.patrec.2011.03.022 | volume=32|issue=10|journal=Pattern Recognition Letters|pages=1436–1446|year=2011|last1=Biggio|first1=Battista|last2=Fumera|first2=Giorgio|last3=Pillai|first3=Ignazio|last4=Roli|first4=Fabio| bibcode=2011PaReL..32.1436B }} Volume 32, Issue 10, 15 July 2011, Pages 1436-1446, ISSN 0167-8655.</ref> is an obfuscation method by which text of the message is stored as a [[GIF]] or [[JPEG]] image and displayed in the email. This prevents text-based spam filters from detecting and blocking spam messages. Image spam was reportedly used in the mid-2000s to advertise "[[pump and dump]]" stocks.<ref name="techtarget">{{cite news|author=Eric B. Parizo|title=Image spam paints a troubling picture|url=http://searchsecurity.techtarget.com/originalContent/0,289142,sid14_gci1204126,00.html|publisher=Search Security|date=2006-07-26|access-date=2007-01-06|archive-date=2007-02-24|archive-url=https://web.archive.org/web/20070224152029/http://searchsecurity.techtarget.com/originalContent/0%2C289142%2Csid14_gci1204126%2C00.html|url-status=live}}</ref>

Often, image spam contains nonsensical, computer-generated text which simply annoys the reader. However, new technology in some programs tries to read the images by attempting to find text in these images. These programs are not very accurate, and sometimes filter out innocent images of products, such as a box that has words on it.

A newer technique, however, is to use an animated [[GIF]] image that does not contain clear text in its initial frame, or to contort the shapes of letters in the image (as in [[CAPTCHA]]) to avoid detection by [[optical character recognition]] tools.