Trying to read files from the past…

In the deeper directories of my storage device I have some files around from the old times, when my general purpose computer was still locked partially by proprietary (operating) systems. Never-the-less e.g. Corel Draw was still worth the lock and the money, I loved that program and what it enabled me to produce.

These products are still around. And are basically binary blobs now for me, the content not readable by the software I use. Blame on that software 🙂 Well, but also the old software, i.e. Corel Draw, and its makers, using a storage format which seems not published and possibly only available by something like a Technology Partner program or similar, meaning lawyers and businessmen, not fun. But those files’ content is mine, and I completely dislike that the format binds me to a certain software.

Searching for FLOSS code that can understand files in Corel Draw’s CDR file format I discovered UniConvertor from the sK1 project and some initial code for LibreOffice, even actively developed ATM, but nothing for Karbon from the Calligra Suite.

Seeing with the hex editor Okteta (jay!) that the CDR file format is based on some RIFF and finding that one completely described on Wikipedia I somehow got tempted to try to develop a CDR import filter for Karbon, to finally free my content from those binary blobs again. And there was quickly some initial success, so I may try to stay with that combining game of decoding bytes:

At least the by-product libkoralle, a Qt-based library for parsing RIFF is useful already.

I look forward to others joining the efforts on the Karbon CDR import filter. I am mainly interested to read files of the versions 4 and 5, so people with newer versions need to make sure support for these themselves 🙂 I still also need to contact the developers of UniConvertor and libcdr (if you are one, check your email box the next days 😉 ).

You can find the current state in the branch “CDRImport” in my clone of the Calligra repo “filters-karbon-cdr” in the official Calligra repo (Updated January 28, 2012).