studyforrest.org Dataset
************************
|license| |access|
Template images and image space transformations
===============================================
This repository contains data derived from the raw data releases of the
*studyforrest.org* project. In particular these are:
* participant/scan-specific template images
* transformation between these respective image spaces
For more information about the project visit: http://studyforrest.org
File name conventions
---------------------
Each directory in the subject directories and the "templates" directory
corresponds to one image template. Templates in ``sub*`` directories are
participant-specific (not aligned across participants). However, templates with
the same name have corresponding input data. Templates in the ``templates``
directory have been derived from all participants, and there are typically
transformation from participant specific templates into the group template
space provided. Group template images carry a ``grp`` prefix in their label.
All transformations are the output if FSL tools: either MAT files with
4x4 affine transformation matrices from FLIRT, or FNIRT warp files.
Here is an example of how transformations can be located. The transformation
of the template image created from all 3T BOLD images of participant ``01``
acquired in phase 2 of the project into the group template space for 3T BOLD
scans can be found in:
``sub-01/bold3Tp2/in_grpbold3Tp2/subj2tmpl_warp.nii.gz``
Each template directory contains one or more image files with more-or-less
self-explanatory names, such as "head", "brain", or "brain_mask". File with
such a name in the one of the ``in_*`` folders represent the image in the parent
folder, aligned and resliced to the target space for this transformation.
These images can be used to inspect the quality of the transformation.
Lastly, the ``code/`` directory contains the source code for computing template
images and transformation between them.
How to obtain the dataset
-------------------------
This repository is a `DataLad `__ dataset. It provides
fine-grained data access down to the level of individual files, and allows for
tracking future updates up to the level of single files. In order to use
this repository for data retrieval, `DataLad `_ is
required. It is a free and open source command line tool, available for all
major operating systems, and builds up on Git and `git-annex
`__ to allow sharing, synchronizing, and
version controlling collections of large files. You can find information on
how to install DataLad at `handbook.datalad.org/en/latest/intro/installation.html
`_.
Get the dataset
^^^^^^^^^^^^^^^
A DataLad dataset can be ``cloned`` by running::
datalad clone
Once a dataset is cloned, it is a light-weight directory on your local machine.
At this point, it contains only small metadata and information on the
identity of the files in the dataset, but not actual *content* of the
(sometimes large) data files.
Retrieve dataset content
^^^^^^^^^^^^^^^^^^^^^^^^
After cloning a dataset, you can retrieve file contents by running::
datalad get
This command will trigger a download of the files, directories, or
subdatasets you have specified.
DataLad datasets can contain other datasets, so called *subdatasets*. If you
clone the top-level dataset, subdatasets do not yet contain metadata and
information on the identity of files, but appear to be empty directories. In
order to retrieve file availability metadata in subdatasets, run::
datalad get -n
Afterwards, you can browse the retrieved metadata to find out about
subdataset contents, and retrieve individual files with ``datalad get``. If you
use ``datalad get ``, all contents of the subdataset will
be downloaded at once.
Stay up-to-date
^^^^^^^^^^^^^^^
DataLad datasets can be updated. The command ``datalad update`` will *fetch*
updates and store them on a different branch (by default
``remotes/origin/master``). Running::
datalad update --merge
will *pull* available updates and integrate them in one go.
More information
^^^^^^^^^^^^^^^^
More information on DataLad and how to use it can be found in the DataLad Handbook at
`handbook.datalad.org `_. The
chapter "DataLad datasets" can help you to familiarize yourself with the
concept of a dataset.
.. _Git: http://www.git-scm.com
.. _git-annex: http://git-annex.branchable.com/
.. |license|
image:: https://img.shields.io/badge/license-PDDL-blue.svg
:target: http://opendatacommons.org/licenses/pddl/summary
:alt: PDDL-licensed
.. |access|
image:: https://img.shields.io/badge/data_access-unrestricted-green.svg
:alt: No registration or authentication required
