iniPetFifList: Initializes a Header for PET or FIF File

Description

The function initializes a list with values that corresponds to a header of a ".pet" or a ".fif" file. The file structures of these formats are explicitly described in the functions readData and writeData of this package.

Usage

iniPetFifList(listType = "pet", data = NULL, imType = "normal")

Arguments

listType

Can be chosen between "pet" and "fif". Default is listType = "pet" to generate a default header for ".pet"-files. Choose listType = "fif" to generate a default header for ".fif"-files.

data

Using data, it is possible to consign the matrix corresponding to the list and to generate the parameters SignalDim, XYmin, DeltaXY and SignalMinMax with default values. Otherwise, if data = NULL these values will be set to NULL and you will have to specify these values.

imType

(character) imType specifies the type of image and thus the default values of the list. Default is imType="normal". It is also implemented imType="radon", i.e. that the image is a sinogram (radon transformed image).

Value

Returns a list with above structure.

Details

Set listType="pet" to generate a list with the following structure. It is assumed that data is a matrix and not equal to NULL.

Description	Contains a short description of the image. The maximal number
	of characters has to be 80. Defaults to `Description="}\eqn{\backslash 0}{\0}\code{"`.
SignalDim	Contains the number of rows and columns of the matrix.
	Defaults to `SignalDim=dim(data)`.
XYmin	Leftmost coordinate and lowest coordinate in the original
	image. If `imType="normal"` then defaults to `XYmin=`
	`-0.5*(dim(data)-1)` or if `imType="radon"` then
	defaults to `XYmin=c(0, -0.5*(ncol(data)-1))`.
DeltaXY	Quantization steps in the original image in \(x\) and \(y\) direction.
	If `imType="normal"` then defaults to `DeltaXY=c(1,1)`
	or if `imType="radon"` then defaults to `DeltaXY=`
	`c(pi/(nrow(data)),1)`.

Set listType="fif" to generate a list, with the following structure. It is assumed that data is a matrix and not equal to NULL.

FIFIdType	ID used to restore FIF:17737:'\(\backslash 0\)''\(\backslash 0\)''E''I'. Defaults to
	`FIFIdType=17737`.
FileName	Name used for saving/restoring this image. Defaults to
	`FileName="}\eqn{\backslash 0}{\0}\code{"`.
Description	See above.
Date	Date (YYYY-MM-DD). Defaults to `Date=`
	`as.character(Sys.Date())`.
SignalDim	See above.
ArrayType	Defines the format number. 1 for Real and 2 for Complex.
	Complex matrices are determined by \(A=a_{i,j}\)
	where \(a_{i,2n}\) is the imaginary part to the real value
	\(a_{i,2n-1}\), \(i=1,\ldots,M\), \(j=1,\ldots,2N\), \(n=1,\ldots,N\).
	Defaults to `ArrayType=1`.
XYmin	See above.
DeltaXY	See above.
SignalMinMax	The lowest and highest signal value in the matrix. Defaults
	to `SignalMinMax=c(min(data), max(data))`.

Examples

Run this code

# NOT RUN {
A <- phantom()
PetList <- iniPetFifList(data = A, imType = "normal")
PetList
rm(A,PetList)
# }