What is the state of the art in HTML content extraction?

Question

There\'s a lot of scholarly work on HTML content extraction, e.g., Gupta & Kaiser (2005) Extracting Content from Accessible Web Pages, and some signs of interest here, e.g.,

Answer 1

I've worked with Peter Rowell down through the years on a wide variety of information retrieval projects, many of which involved very difficult text extraction from a diversity of markup sources.

Currently I'm focused on knowledge extraction from "firehose" sources such as Google, including their RSS pipes that vacuum up huge amounts of local, regional, national and international news articles. In many cases titles are rich and meaningful, but are only "hooks" used to draw traffic to a Web site where the actual article is a meaningless paragraph. This appears to be a sort of "spam in reverse" designed to boost traffic ratings.

To rank articles even with the simplest metric of article length you have to be able to extract content from the markup. The exotic markup and scripting that dominates Web content these days breaks most open source parsing packages such as Beautiful Soup when applied to large volumes characteristic of Google and similar sources. I've found that 30% or more of mined articles break these packages as a rule of thumb. This has caused us to refocus on developing very low level, intelligent, character based parsers to separate the raw text from the markup and scripting. The more fine grained your parsing (i.e. partitioning of content) the more intelligent (and hand made) your tools must be. To make things even more interesting, you have a moving target as web authoring continues to morph and change with the development of new scripting approaches, markup, and language extensions. This tends to favor service based information delivery as opposed to "shrink wrapped" applications.

Looking back over the years there appears to have been very few scholarly papers written about the low level mechanics (i.e. the "practice of the former" you refer to) of such extraction, probably because it's so domain and content specific.