I'm trying to create accessible PDFs directly from a web page (output via a custom page template from a the CMS I'm working with) by using Adobe Acrobat's Create PDF from Web Page feature. The results aren't bad -- PDF tags seem to be in place and correct, and I'm creating the page that the PDF is created from specifically to minimise reading order problems. However, running Acrobat's full accessibility check reports that none of the images have any ALT text, despite them all have the alt attribute correctly set in the original HTML of the web page.
Does anyone know how to force Acrobat to recognise ALT text in the source HTML and correctly attach it to the image when generating a PDF from a web page?
Google hasn't provided me with any useful answers thus far.