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 UVW - Universal VTK Writer
 ==========================
 
 UVW is a small utility library to write VTK files from data contained in Numpy arrays. It handles fully-fledged `ndarrays` defined over {1, 2, 3}-d domains, with arbitrary number of components. There are no constraints on the particular order of components, although copy of data can be avoided if the array is Fortran contiguous, as VTK files are written in Fortran order. Future developments will include multi-process write support.
 
 ## Getting Started
 
 Here is how to install and use `uvw`.
 
 ### Prerequisites
 
 * Python 3. It may work with python 2, but it hasn't been tested.
 * [Numpy](http://www.numpy.org/). This code has been tested with Numpy version 1.14.3.
 
 ### Installing
 
 This library can be installed with `pip`:
 
 ```
 pip install --user git+https://c4science.ch/source/uvw.git
 ```
 
 ### Writing Numpy arrays
 
 As a first example, let us write a multi-component numpy array into a rectilinear grid:
 
   lang=python
   import numpy as np
   from uvw import RectilinearGrid, DataArray
   
   # Creating coordinates
   x = np.linspace(-0.5, 0.5, 10)
   y = np.linspace(-0.5, 0.5, 20)
   z = np.linspace(-0.9, 0.9, 30)
   
   # Creating the file
   grid = RectilinearGrid('grid.vtr', (x, y, z))
   
   # A centered ball
   x, y, z = np.meshgrid(x, y, z, indexing='ij')
   r = np.sqrt(x**2 + y**2 + z**2)
   ball = r < 0.3
   
   # Some multi-component multi-dimensional data
   data = np.zeros([10, 20, 30, 3, 3])
   data[ball, ...] = np.array([[0, 1, 0],
                               [1, 0, 0],
                               [0, 1, 1]])
   
   
   # Adding the point data (see help(DataArray) for more info)
   grid.addPointData(DataArray(data, range(3), 'data'))
   grid.write()
 
 UVW also supports writing data on 2D and 1D physical domains, for example:
 
   lang=python
   import numpy as np
   from uvw import RectilinearGrid, DataArray
   
   # Creating coordinates
   x = np.linspace(-0.5, 0.5, 10)
   y = np.linspace(-0.5, 0.5, 20)
   
   # Creating the file
   grid = RectilinearGrid('grid.vtr', (x, y))
   
   # A centered disk
   x, y = np.meshgrid(x, y, indexing='ij')
   r = np.sqrt(x**2 + y**2)
   R = 0.3
   disk = r < R
   
   data = np.zeros([10, 20])
   data[disk] = np.sqrt(1-(r[disk]/R)**2)
   
   # Adding the point data (see help(DataArray) for more info)
   grid.addPointData(DataArray(data, range(2), 'data'))
   grid.write()
 
 
 ## List of features
 
 Here is a list of what is available in UVW:
 
 ### VTK file formats
 
+- Image data (`.vti`)
 - Rectilinear grid (`.vtr`)
 
 ### Data representation
 
 - ASCII
 - Base64 (uncompressed)
 
 ### Planned developments
 
 Here is a list of future developments:
 
-- [ ] Image data
+- [x] Image data
 - [ ] Unstructured grid
 - [ ] Structured grid
 - [ ] Parallel writing (multi-process)
 - [ ] Benchmarking + performance comparison with [pyevtk](https://bitbucket.org/pauloh/pyevtk)
 
 
 ## Developing
 
 These instructions will get you a copy of the project up and running on your local machine for development and testing purposes.
 
 ### Git repository
 
 First clone the git repository:
 
 ```
 git clone https://c4science.ch/source/uvw.git
 ```
 
 Then you can use pip in development mode (possibly in [virtualenv](https://virtualenv.pypa.io/en/stable/)):
 
 ```
 pip install --user -e .
 ```
 
 ## Running the tests
 
 The tests can be run using [pytest](https://docs.pytest.org/en/latest/):
 
 ```
 pytest tests
 ```
 
 ## License
 
 This project is licensed under the MIT License - see the LICENSE.md file for details.
 
 ## Acknowledgments
 
 * [@PurpleBooth](https://github.com/PurpleBooth)'s [README-Template](https://gist.github.com/PurpleBooth/109311bb0361f32d87a2)