Data download

Registered participants have access to a set of multi-slice multi-echo coil-combined data from a variety of anatomy, scanners, and field strengths (1.5 and 3T).

The data are available in either Matlab format or raw input format:

Matlab1 format

Each file is named numerically, corresponding to one case, e.g. 01.mat, 02.mat, etc. The data structure of each file is in accordance with the ISMRM water-fat toolbox as follows. Each file has a variable called either data or imDataParams with the following fields:

  images Images at different TE with complex-valued intensities. 5D array of size X x Y x Z x (no. coils) x (no. echoes)
  TE (no. echoes) x 1 array with the echo times in seconds
  FieldStrength Scalar value in Tesla
  PrecessionIsClockwise Sign/direction of precession
If +1, main fat peak at +217Hz at 1.5T oscillates as exp(-i 2 pi 217 TE)
If -1 or 0, it oscillates as exp(+i 2 pi 217 TE)
  mask Mask for judging the submitted results

Raw input format

Each case contains 4 files, named numerically, e.g. 01.txt and 01.raw for case 1, 02.txt and 02.raw for case 2, etc.

  • XX.txt is a header file in ASCII text, with 3 lines:
    • Line 1 contains 5 tab-separated numbers representing Complex, X matrix size, Y matrix size, Z matrix size, number of echoes. The first number is 1 for complex data, and 0 for real data.
    • Line 2 contains the tab-separated echo times in seconds
    • Line 3 contains a single number representing the field strength
  • XX.raw is a corresponding little-endian raster file with single-precision (32-bit) floats, with real and imaginary values interleaved. Precession with positive frequency is clockwise i.e. main fat peak at +217Hz at 1.5T oscillates as exp(-i 2 pi 217 TE).
  • XX_mask.txt is a header file in ASCII text with one line, same format as first line in XX.txt
    • Line 1 contains 5 tab-separated numbers representing Complex, X matrix size, Y matrix size, Z matrix size, number of echoes. The first number is 1 for complex data, and 0 for real data.
  • XX_mask.raw is a mask file in little-endian raster file with single-precision (32-bit) floats.

     

    Sample scripts to read and write Raw data format
    (Provided AS IS, without guarantee; please send us improvements to the code you are willing to share with the community)


    1 Mathworks, Natick, MA
    2 Exelis Visual Information Solutions, Inc.

Click
here to
download