ivt2html utility cleverly converts .ivt files to regular HTML with ease.
Installing ivt2html is relatively easy as you just need to make a copy of the program and manually move it to a bin directory. Furthermore, you can make use of the included ivtdump and mszpdump programs, which are beneficial for those who are looking to debug or extend ivt2html.
At its core, the .ivt files represent simple containers composed of multiple other files, with some files compressed using standard Microsoft compression methods. There are a variety of compressed files, with one containing the compressed HTML content, another potentially containing an optional CSS file, and yet another file that offers table of contents information. Additionally, there are uncompressed stoplist files and differently compressed findex files to consider.
It is also worth noting that .ivi files can be dumped with ivtdump, and there are a group of files within both .ivt and .ivi files. The ones compressed with the header mszp and nszp can be decompressed with mszpdump while the others are either plain text (like stoplist files) or trivially compressed (like ftindex files). Stoplist files include words that shouldn't be searched for, like meta tags, while ftindex files contain words that should be searched for with a search engine. Although decompressing the ftindex words via hacked code is possible, it's not essential to the process, so work on that was ultimately discontinued.
Version 1.1.1: N/A