Centroids image features FINDCENT
The initial positions associated with each image are given in formatted files whose names are determined either using the CCDPACK image extension item CURRENT_LIST (which is maintained by list processing CCDPACK applications) or from an explicit list of names.
"
automatically"
adjust the
centroid location parameters to reflect the fact that picking good initial positions is less likely when
dealing with very large images (these tend to be displayed using one display pixel to represent many
image pixels).
If TRUE then the values of the parameters ISIZE, TOLER and MAXSHIFT are scaled by an amount that maps the largest dimension of each input image to an image of size 1024 square (so an image of size 2048 square will have these parameters increased by a factor of two). [FALSE]
The names of the input lists may use modifications of the input image names, so for instance if the
position lists are stored in files with the same name as the input images but with a file type of "
.dat"
instead of "
.sdf"
then use:
INLIST .dat
If the input list names are a modification of the image names say with a trailing type of
"
_initial.positions"
. Then a response of:
INLIST _initial.positions
will access the correct files. Names may also use substitution elements, say the image names are _data and the position lists are _pos.dat, then a response like:
INLIST datapos.dat
may be used. If a naming scheme has not been used then an explicit list of names should be returned (wildcards cannot be used to specify list names). These names should be given in the same order as the input image names and may use indirection elements as well as names separated by commas. A listing of the input image name order (after any wildcard expansions etc. have been made) is shown to make sure that the order is correct.
If the logging system has been initialised using CCDSETUP, then the value specified there will be
used. Otherwise, the default is "
CCDPACK.LOG"
. [CCDPACK.LOG]
TERMINAL – Send output to the terminal only
LOGFILE – Send output to the logfile only (see the LOGFILE parameter)
BOTH – Send output to both the terminal and the logfile
NEITHER – Produce no output at all
If the logging system has been initialised using CCDSETUP, then the value specified there will be
used. Otherwise, the default is "
BOTH"
. [BOTH]
"
CURRENT_LIST"
of the input images. The names will be present in the
extension if the positions were located using a CCDPACK application (such as IDICURS).
Using this facility allows the transparent propagation of position lists through processing
chains.
If a global value for this parameter has been set using CCDSETUP then that value will be used. [TRUE]
OUTLIST .cent
Or alternatively you can use an explicit list of names. These may use indirection elements as well as names separated by commas. [.cent]
’
’
outlist=’
.cent’
"
input"
lists). ’
"
image1,image2,image3"
’
’
"
image1.pos,image2.pos,image3.pos"
’
outlist=’
.acc’
namelist=new_position_lists Position list formats.
CCDPACK supports data in two formats.
CCDPACK format – the first three columns are interpreted as the following.
Column 1: an integer identifier
Column 2: the X position
Column 3: the Y position
The column one value must be an integer and is used to identify positions which are the same but which have different locations on different images. Values in any other (trailing) columns are usually ignored.
EXTERNAL format – positions are specified using just an X and a Y entry and no other entries.
Column 1: the X position
Column 2: the Y position
This format is used by KAPPA applications such as CURSOR.
Comments may be included in a file using the characters "
#"
and "
!"
. Columns may be separated by
the use of commas or spaces.
Data following the third column is copied without modification into the results files
In all cases, the coordinates in position lists are pixel coordinates.
NDF extension items.
If NDFNAMES is TRUE then the item "
CURRENT_LIST"
of the .MORE.CCDPACK structure of the
input images will be located and assumed to contain the names of the lists whose positions are to
be centroided. On exit this item will be updated to reference the name of the centroided
list of positions.
"
current"
value is the value assigned on the last run of the application. If the
application has not been run then the "
intrinsic"
defaults, as shown in the parameter help,
apply.
Retaining parameter values has the advantage of allowing you to define the default behaviour of the application but does mean that additional care needs to be taken when using the application on new datasets or after a break of sometime. The intrinsic default behaviour of the application may be restored by using the RESET keyword on the command line.
Certain parameters (LOGTO, LOGFILE and NDFNAMES) have global values. These global values will always take precedence, except when an assignment is made on the command line. Global values may be set and reset using the CCDSETUP and CCDCLEAR commands.
This routine correctly processes the DATA and QUALITY components of an NDF data structure. Bad pixels and all non-complex numeric data types can be handled.