In addition to the generic FME feature attributes that FME Workbench adds to all features (see About Feature Type Attributes), this format also adds format-specific attributes (Format Attributes).
Some of the information contained in the NIfTI header is exposed as a feature attribute in FME.
|
Attribute Name |
Contents |
|---|---|
|
intent_code |
A code that indicates the meaning of the contained data. The NIfTI standard specifies some values in the NIfTI Data Format Documentation, NIFTI1_INTENT_CODES. Note that some applications may define their own custom intent codes. Type: int32 Default: 0 (unknown) |
|
intent_parameter_1, intent_parameter_2, intent_parameter_3 |
These parameters further describe the intent, and their definitions depend on the intent codes. When required by a recognized intent code, they will show up in the intent description. These parameters are always stored as a double, but in certain cases should be interpreted as integers (for example, degrees of freedom). Type: double Default: 0 |
|
nifti_intent_description |
Where possible, the NIfTI reader will supply a string that describes the data content of each cell. This is generated as an interpretation of the intent code and parameters. Type: string |
|
intent_name |
A string stored in a NIfTI file that can be used to provide additional information about the data. Type: string |
|
nifti_units_x, nifti_units_y, nifti_units_z, nifti_units_t |
Units of measurement of the image axis, with one of the following values:
In a well-formed NIfTI file, the first three (x,y,z) units should always be spatial, and the last three units should be temporal (t). Type: string Default: Unknown |
|
frequency_direction, |
Optional fMRI specific information. String that indicates the encoding direction of phase, frequency and slice. Note that if the slice_direction is specified as x or y, the slices read by FME won’t overlap with the slices acquired by the fMRI equipment. Type: string Default: 0 |
|
nifti_description |
A short string stored in an NIfTI file that describes the image. Type: string |
|
nifti_slice_duration |
Usually specific to fMRI images, indicate how long it took to acquire the slice. Note that if the slice_direction is specified as x or y, the slices read by FME won’t overlap with the slices acquired by the fMRI equipment. Type: double |
|
nifti_first_aquired_slice, nifti_last_aquired_slice |
Indicate the first and the last slices that were gathered by the acquisition equipment. Other slices are added as padding to the file. Slice numbers must be positive whole numbers. Note that if the slice_direction is specified as x or y, the slices read by FME won’t overlap with the slices acquired by the fMRI equipment. Type: int64 Default: 0 |
|
nifti_calibration_max, nifti_calibration_min |
Indicate the maximum and minimum display values for visualization. Pixel values higher than or equal to the calibration max should be displayed at maximum brightness, while values lower than the calibration minimum should be displayed. Note: Not all NIfTI applications set these attributes, and the FME Data Inspector will ignore them. Type: double Default: 0 |
|
nifti_type |
This will always be nifti_raster_slice. |
Each slice will also have the following specific attribution:
|
Attribute |
Description |
|---|---|
|
nifti_volume_number |
When reading, identifies the originating volume in the source NIfTI file. When writing, used to group incoming raster slices into volumes. Volume numbers must be positive, contiguous, whole numbers starting at zero (for example, 0, 1, 2, 3). Type: int64 |