Three kinds of Bengali PDF
A Bengali PDF made from a Unicode document carries its text inside, and converting it is extraction. A scanned Bengali PDF is pictures of pages and has to be recognised first, with the accuracy described on our Bengali OCR page. A third kind is common in Bangladesh and West Bengal: text typed in Bijoy. It looks like Bengali on the page, but the file holds something else, and neither extraction nor OCR is the right tool for it.
Bijoy and SutonnyMJ
Bijoy was released by Ananda Computers in 1988 and set Bangladesh’s newspapers, government print and textbooks for decades. Text typed in Bijoy stores ordinary Latin letters that the SutonnyMJ font draws as Bengali: বাংলা is stored as evsjv. Copy from such a PDF and those Latin letters are what you get. Our legacy converter reads the stored letters through a Bijoy table built by drawing every code in SutonnyMJ itself. Choose Bengali — Bijoy (SutonnyMJ) in its script list rather than relying on detection. The table has not yet been checked by a Bengali reader, and the converted document says so.
What comes through
Text, paragraph breaks and reading order come through. Fonts and exact layout are approximated, because the aim is a document you can edit rather than a copy of the page. Conjuncts are written with the hasanta, so any Unicode Bengali font on the machine opening the file draws them joined.