Public Attributes
char	descrip [80]

char	aux_file [24]

char	orient

char	originator [10]

char	generated [10]

char	scannum [10]

char	patient_id [10]

char	exp_date [10]

char	exp_time [10]

char	hist_un0 [3]

int	views

int	vols_added

int	start_field

int	field_skip

int	omax

int	omin

int	smax

int	smin

Detailed Description

Most of these are historical, relevant to use with the Dynamic Spatial Reconstructor scanner developed at the Mayo BIR in the late 70's and through the 80's. However, the 'orient' field is very important and is used to indicate individual slice orientation and determines whether the Analyze 'Movie' program will attempt to flip the images before displaying a movie sequence. It is perfectly acceptable to put any values you want into those fields because they do not(should not) affect image processing.

(c) Copyright, 1986-1995
Biomedical Imaging Resource
Mayo Foundation

Member Data Documentation

char itk::data_history::aux_file[24]

A place to put the name of an auxiliary file to use instead of the default .img file. This is not currently used by the Analyze program.

char itk::data_history::descrip[80]

A place to put a short description of the data

char itk::data_history::exp_date[10]

Experiment date - these were used for DSR experiments

char itk::data_history::exp_time[10]

Experiment time - these were used for DSR experiments

int itk::data_history::field_skip

Video field skip factor used in the reconstructed image - these were used for DSR experiments

char itk::data_history::generated[10]

The date the image was generated.

char itk::data_history::hist_un0[3]

Unused padding of the structure

int itk::data_history::omax

The omax/omin and smax/smin relate to rescaling of the value range via the Load process, where both the 'original' omax/omin and the 'scaled' omax/omin could be set to rescale the value range of the data when it is loaded.

int itk::data_history::omin

See also: data_history::omax

char itk::data_history::orient

The 'orient' field in the data_history structure specifies the primary orientation of the data as it is stored in the file on disk. This usually corresponds to the orientation in the plane of acquisition, given that this would correspond to the order in which the data is written to disk by the scanner or other software application.

It would be vary rare that you would ever encounter any old ANALYZE 7.5 files that contain values of 'orient' which indicate that the data has been 'flipped'. The 'flipped flag' values were really only used internal to the Analyze program to precondition data for fast display in the Movie module, where the images were actually flipped vertically in order to accommodate the raster paint order on older graphics devices. The only cases you will encounter will have values of 0, 1, or 2.

hdr->orient "MayoClinic/Analyze" Origin dims[1] dims[2] dims[3]
======================================================================
0 transverse-unflipped IRP R->L P->A I->S
1 coronal-unflipped IRP R->L I->S P->A
2 sagittal-unflipped IRP P->A I->S R->L
3 transverse-flipped IRA R->L A->P I->S
4 coronal-flipped SRP R->L S->I P->A
5 sagittal-flipped ILP P->A I->S L->R
Where the Origin disignators are with respect to the patient
[(I)nferior|(S)uperior] [(L}eft|(R)ight] [(A)nterior|(P)osterior]

SPECIAL NOTE: THE BEHAVIOR OF THIS IO ROUTINE DIFFERS FROM THAT OF ANALYZE! NO RE_ORIENTATION OF THE DATA WILL OCCUR IN THE ITK IMPLEMENTATION. Upon loading into the Analyze program, all data is reoriented into the 3D Analyze Coordinate System. The orientation of patient anatomy in the 3D Analyze Coordinate System has a fixed orientation relative to each of the orthogonal axes. This coordinate system does fix the origin in the subject's Inferior-Right-Posterior location relative to anatomy, with a left-handed coordinate system for specification of the other anatomy relative to the axes as given here: