How to decode bank.work files as a third party app?

[c13303]

Hi fellow Elektronauts

I’m a web/software developper by day and electronic music player by night. 10 years of Octrack and more than ever my favorite live performance weapon.

I’d like to write my own sample/file manager, in order to copy pattern/parts from project to project a bit faster than just by hand. (I do have Octaedit but it never worked for me. I want something more simple and efficient)

I know programming, but I have a question to get started : how do you read the bank files ? (bank[00].work) Those are containing the patterns and the parts info, but you can’t read anything with just opening it.
Are they compiled ? Is there any documentation for decompiling/decoding/reading/editing those files ? Can’t find anything about it on Google, but I know it’s possible since third party software such as OctaEdit are doing it.

I guess if I can resolve this, I would be able to deal with the rest of the task. Thanks for any information.

[vblr]

@c13303

I guess if I can resolve this, I would be able to deal with the rest of the task. Thanks for any information.

Yeah, that’s usually how it goes

Reverse engineering is a whole topic and it’s hard to get into for sure. I won’t claim to be an expert myself, and haven’t looked into any of the formats Elektron uses.

But reading up on reverse engineering and practicing with easier formats is a good beginning.

Personally I like the most to read practical reverse engineering processes that people publishes as blog posts, and then pick up whatever tips I come across in those posts. I don’t have any collection of those at hand though. Best is to go through resources like Hackaday and similar sites, pick up interesting posts.

That said, here are some general starting points:

• RE guide for beginners: Methodology and tools - Reverse Engineering - 0x00sec - The Home of the Hacker
• https://github.com/0xZ0F/Z0FCourse_ReverseEngineering
• https://www.begin.re/
• https://ghidra-sre.org/
• Introduction to reverse engineering and Assembly. | KaKaRoTo's Blog
• https://beginners.re/

Hope those are a bit helpful at least

[c13303]

Thanks a lot for this.
Well I wasn’t expecting it to require proper reverse engineering, thought it could be some regular compression stuff, but I may be dreaming. For sure the Octatrack hardware must require its own format. You believe Octaedit (and this Octobus we start to hearabout) did reverse engineering ?

I would therefore understand why there aren’t more OT editors

EDIT : actually found an old topic as a confirmation

Open source file format?

Will there ever be a possibility to open-source the OT project file format? Not the code that runs the sequencer or the DSP effects, just the information stored in the files. It could be nice to load a project file in a computer editor and see the pattern data, or especially for building arrangements, which can be a bit tricky on the small screen. If not, would it be OK for someone to reverse-engineer the format and build such an editor?

Well I guess Elektron never released the format. But @Rusty from Octaedit says he wasn’t willing to do reverse engineering as well. Did he in the end ?

[vblr]

If you have a file with a particular format but nothing published about how that format works, you’re gonna have to reverse engineer it, one way or another. Lets say it’s just a .zip file so you try to unzip it and it worked, but those instructions were not published anywhere, that’s still reverse engineering, even though it was an easy one

If OctaEdit is reading those file formats and there is no specification written and published for the public about those file formats, then Rusty did indeed do some reverse engineering to understand, read and write that format.

[phading]

If only there was a group of people with more inside info, personal interest, financial motives, logistical conditions, etc, for this project…

Sorry about the non-helpful reply, but I’m frustratingly craving the simple ability of transfering patterns through projects for more than 10 years too.