What does an Area Description File (ADF) looks like?

Question

I'm starting to work with the Google Tango Tablet, hopefully to create (basic) 2D / 3D maps from scanned areas. But first I would like to read as much about the Tango (sensors / API) as I can, in order to create a plan to be as time efficient as possible.

I instantly noticed the ability to learn areas, which is a very interesting concept, nevertheless I couldn't find anything about these so called Area Description Files (ADF).

I know the ADF files can be geographically referenced, that they contain metadata and an unique UUID. Furthermore I know their basic functionalities, but that's about it.

In some parts of the modules ADF files are referred to as 'maps', in other parts they are just called 'descriptions'.

So what do these files look like? Are they already basic (GRID) (2D) maps, or are they just descriptions? I know there are people who already extracted the ADF files, so any help would be greatly appreciated!

Answer 1

From Tango ADF Doco

Important: Saved area descriptions do not directly record images or video of the location, but rather contain descriptions of images of the environment in a very compressed form. While those descriptions can’t be directly viewed as images, it is in principle possible to write an algorithm that can reconstruct a viewable image. Therefore, you must ask the user for permission before saving any of their learned areas to the cloud or sharing areas between users to protect the user's privacy, just as you would treat images and video.

Other than that there doesn't seem to be much info about the file internals - I use a lot of them, but I've never been compelled to look inside - curious yes, but not compelled

Answer 2

Without any direct info from the project Tango folks anything we provide would be merely speculation. I'm with Mark, not much compelling reason to get details. My speculation: probably contains a set of image descriptors, like SIFT, and whatever other known device settings are available, like GPS location, orientation (gravity), time(?), etc.

Answer 3

I got the ADF file, basically coded binaries and seems difficult to decode.

I will be happy to share the file if anyone is still interested.