skyview.executive
Class Imager

java.lang.Object
  extended by skyview.executive.Imager

public class Imager
extends java.lang.Object

This class generates an image or images from user inputs. Output images are created by sampling one or more input images into a user specified grid of pixels.
Usage:
java skyview.geometry.test.Imager [key=value] [key=value] ...
If the code is being executed from Jar file, then use
java -jar skyview.jar [key=value] [key=value]...
The field keys are not case sensitive but the values may be.

Valid field keys include:

Lon
The longitude of the center of the output image in the coordinate system selected. Note that the default coordinate system is J2000, so the longitude is the right ascension. The value is specified in decimal degrees.
Lat
The latitude of the center of the output image in the coordinate system selected. J2000 is the default coordinate system, so by default Lat corresponds to declination. The value is specified in decimal degrees.
Position
The comma separated longitude and latitude. If Position and Lon/Lat are specified then the values specified in Lon/Lat override those in position.
Coordinates
A string describing the coordinate system to be used for the output image. It comprises an inital letter which gives the coordiante system, which prefixes a number giving the epoch of the coordiante system.
  • J: Julian (FK5) coordiantes, e.g., J2000.
  • B: Besselian coordinates, e.g., B1950.
  • E: Julian Ecliptic coordinates, e.g., E2000.
  • H: Helioecliptic coordinates (i.e., coordinates centered on the instantaneous position of the sun), e.g., H2002.4356.
  • G: Galactic coordinates. Characters after the first are ignored.
  • I: ICRS coordinates. Characters after the first are ignored.
Projection:
The projection used to convert from celestial to plane coordinates. The projection string is the 3 character string used in the FITS WCS papers, with only the first letter capitalized. Supported output projections include:
  • Tan: The tangent plane on gnomonic projection.
  • Sin: The sine or orthographic projection.
  • Ait: The Hammer-Aitoff projection.
  • Car: The cartesian or plate-caree projection.
  • Zea: The Zenithal equal area projection
  • Csc: The COBE sperical cube projection.
Sampler:
The sampler defines how the input images are sampled to get values at the putput pixels. Sampling algorithims include:
  • NN: Nearest Neighbor.
  • LI: [Bi-]Linear interpolation.
  • Lanczos[n]: A Lanczos smoothly truncated Sinc interpolator of order n. Lanczos defaults to order 3.
  • Spline[n]: The n'th order spline interpolation. Defaults to cubic splines. The order may range from 2 to 5.
  • Clip: A flux conserving exact area resampler where output pixels serve as clipping windows on the input image.
Scale:
The size of the output pixels in degrees. If the pixels are square only a single values is given. Non-square pixels can be specified as Scale=xsize,ysize.
Size:
The size of the entire image in degrees.
Pixels:
The number of output pixels along an edge. If the output image is not square this can be specified as Pixels=xPixels,yPixels
Rotation:
A rotation in the output plane to be applied to the data (in decimal degrees)
Survey:
The survey from which the output image is to be created. More than one survey can be specified as survey1,survey2,survey3,...
Ebins:
For surveys with a third dimension, the binning to be applied in this dimension. Currently this is specified using as x0,dx,n where x0 is the starting bin for the first output bin, dx is the width of the output bins, and n is the number of output bins. These are expressed in terms of the input energy bins, such that if the survey data has 10 bins, the first bin ranges from 0-1, the second from 1-2 and the last from 9-10. If we wished to rebin this data into four evenly spaced bins excluding the first and last bins, then Ebins=1,2,4. A default binning is defined for each 3-d survey included in SkyView.
Output:
The output file name. If data is being created from more than one survey, then the survey short name will be appended to the name. The default output filename is output.fits. The strings "-" or "stdout" are used to specify writing to the standard output.
Compress:
Write the output in GZIP compressed form. The value field is ignored.
Float:
Write output in 4 byte reals rather than 8 byte. The value field is ignored.

The following options control where the imager task finds survey data.

XMLRoot:
The directory containing the XML survey descriptions
Cache:
Directory location (or locations) where cached files (survey files retrieved from remote locations) are to be found. The first cache location is also used when a remote file is retrieved.
PurgeCache:
Should files cached during this retrieval be deleted after processing? Only files cached during the current operation will be deleted. If there are survey files in the cache area from previous requests that are used in the current request, these will be retained.
SurveyXML:
Gives the name of a file containing an XML description of a survey. This allows the user to create an image from a survey they are describing. Use a "," to separate multiple survey files.
The following operations allow the user to override the basic processing operations.

The following options control the classes that are used in processing the user request. Most users can ignore these.

SurveyFinder:
The class of the object that finds the appropriate survey object for the surveys the user has requested.
ImageFinder
The class of the object that finds the appropriate images within a survey for each pixel of the output object.
PreProcessor:
One or more objects that do image pre-processing.
Mosaicker:
The object that actually generates the output image melding together the input images.
PostProcessor:
One or more classes of object that do image post processing. One example used by default in some surveys is the skyview.geometry.Deedger. You can force de-edging by specifying the class, or turn it off by setting PostProcessor=null.

NoFITS:
Do not create a FITS output file. This could be used for debugging, or more likely in combination with graphics output created by the skyview.ij.IJProcessor where the user wants only a JPEG or GIF and does not need a FITS file. See the help for the IJProcessor for details on supported formats and other options.


Field Summary
protected  double bin0
          The beginning of the first pixel in energy space.
protected  CoordinateSystem c
          The CoordinateSystem object for the output image.
protected  Image[] cand
          The candidate images for use in resampling
protected  double dBin
          The width of pixels in energy space
protected  DepthSampler dsamp
          The energy sampler object used when creaing the output image.
protected  double lat
          The lon/lat (or RA/dec) coordinates of the output image.
protected  double lon
          The lon/lat (or RA/dec) coordinates of the output image.
protected  Processor mos
          The Mosaicker used in generating the ouput image.
protected  Image output
          The current output image
protected  Projection p
          The Projection object for the output image.
protected  Scaler s
          The Scaler object for the output image.
protected  Sampler samp
          The sampler object used to create the output image.
protected  Survey surv
          The current Survey object being used.
 
Constructor Summary
Imager()
          Initialize the imager.
 
Method Summary
 void createFitsFile()
          Create the FITS file
 Image[] getCandidates()
          Get the candidate images that may be used for resampling
 double[] getEdgeAdjustments()
          Get any adjustments made to image intensities to minimize edge effects.
 java.lang.Object getImageData()
          Get the output data as 1-d double array
 double getLat()
          Get the central latitude/declination of the output image
 double getLon()
          Get the central longitude/RA of the output image
 int getPixelDepth()
          Get the energy depth of the output image
 int getPixelHeight()
          Get the height of the output image in pixels
 int getPixelWidth()
          Get the width of the output image in pixels
 java.lang.String getSamplerName()
          Get the sampler name.
 Scaler getScaler()
          Get the Scaler used for the output image.
 Survey getSurvey()
          Get the current survey being processed
static void main(java.lang.String[] args)
          Generate an image given the input parameters.
protected  void processSurvey(int nSurvey, java.lang.String surveyID)
          Process a particular survey.
 void run()
          Run the image
 void run(java.lang.String[] args)
          Run an image with a given set of arguments.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

bin0

protected double bin0
The beginning of the first pixel in energy space.


dBin

protected double dBin
The width of pixels in energy space


s

protected Scaler s
The Scaler object for the output image.


p

protected Projection p
The Projection object for the output image.


c

protected CoordinateSystem c
The CoordinateSystem object for the output image.


samp

protected Sampler samp
The sampler object used to create the output image.


dsamp

protected DepthSampler dsamp
The energy sampler object used when creaing the output image.


lon

protected double lon
The lon/lat (or RA/dec) coordinates of the output image.


lat

protected double lat
The lon/lat (or RA/dec) coordinates of the output image.


surv

protected Survey surv
The current Survey object being used.


cand

protected Image[] cand
The candidate images for use in resampling


output

protected Image output
The current output image


mos

protected Processor mos
The Mosaicker used in generating the ouput image.

Constructor Detail

Imager

public Imager()
Initialize the imager. Make sure that choices have been made for the basic elements needed for running the code.

Method Detail

main

public static void main(java.lang.String[] args)
                 throws java.lang.Exception
Generate an image given the input parameters. See class documentation for usage.

Throws:
java.lang.Exception

getSamplerName

public java.lang.String getSamplerName()
Get the sampler name.


getScaler

public Scaler getScaler()
Get the Scaler used for the output image.


getImageData

public java.lang.Object getImageData()
Get the output data as 1-d double array


getLon

public double getLon()
Get the central longitude/RA of the output image


getLat

public double getLat()
Get the central latitude/declination of the output image


getSurvey

public Survey getSurvey()
Get the current survey being processed


getEdgeAdjustments

public double[] getEdgeAdjustments()
Get any adjustments made to image intensities to minimize edge effects.


getCandidates

public Image[] getCandidates()
Get the candidate images that may be used for resampling


getPixelDepth

public int getPixelDepth()
Get the energy depth of the output image


getPixelWidth

public int getPixelWidth()
Get the width of the output image in pixels


getPixelHeight

public int getPixelHeight()
Get the height of the output image in pixels


run

public void run(java.lang.String[] args)
         throws java.lang.Exception
Run an image with a given set of arguments. Retained for compatibility with V1.00. Putting the argument handling in the main code allows more flexibility in creating Image objects.

Throws:
java.lang.Exception

run

public void run()
         throws java.lang.Exception
Run the image

Throws:
java.lang.Exception

processSurvey

protected void processSurvey(int nSurvey,
                             java.lang.String surveyID)
                      throws java.lang.Exception
Process a particular survey.

Throws:
java.lang.Exception

createFitsFile

public void createFitsFile()
                    throws java.lang.Exception
Create the FITS file

Throws:
java.lang.Exception