When people convert PDF files into HTML files, they tend to be disappointed with the results. The main reason for this tends to be that a straight conversion is not possible. PDF files can contain a large number of structures which have no direct equivalent in HTML (even in the new HTML5). PDF was designed as a format to be viewed – the file is painted onto the page and the user sees the end result. Many PDFs are generated from strips of images or overlapping overlays which need to fit together exactly.
With the latest PDF versions, this is even worse. How do you translate XML, transparency, colorspace models, Javascript and interactive elements into HTML correctly?
People also expect the text in an HTML file to be in the correct order. Because a PDF is generating a ‘picture’ this is not always going to happen. Some PDF creation tools draw the text in very odd ways – I explained this in more detail in a previous article: PDF text. The text looks correct because your brain sees he finished output and interprets it.
If image quality in the HTML is important, you could convert the PDF into a image and display that, but then all interaction is lost and you need big files for high resolution.
When HTML5 , CSS and Javascript are well support, this may well change. But in the meantime (2010), be careful about trying to turn PDF into HTML – try to keep it in PDF if possible or be prepared to live with less than perfect results.
Updated 2012 – since I wrote this, I have indeed had a look at HTML5 and you can read the results in other blog articles.