ISOCAM Interactive Analysis User's Manual Version 5.0 - ISO - ESA

122 CHAPTER 14. IMAGE ANALYSIS AND DISPLAY
14.3 2-D image analysis.
Currently two routines exist for 2-D image analysis. These are xdisp and sad display. You
have met sad display before, see Section 10.2, so here we will give only a brief example of its
use with struct2sad.
14.3.1 xdisp
xdisp is a CIA routine to display and analyse single images. They can be in several formats:
IDL 2-D array, FITS format images, the CCIM from an SAD or images in MIDAS format. It
can interactively display profiles of rows or columns, display histograms, create contour plots
(uses xcontour, see Section 14.7.1), perform simple statistical analyses and compute the Fourier
transform of an image. A recently added feature is the option to interactively save a region of
the displayed image as a FITS file. This FITS file can then be used as an input to other analysis
packages or other CIA routines such as isocont.
14.3.1.1 The xdisp window
Figure 14.4 shows the xdisp window. All the operations described above can be performed by
clicking on the following window buttons:
• quit – Quit the application.
• load – Load an image. Image formats can be fits, MIDAS, SAD or 2-D array.
• lut – Modify the LUT, i.e. call xloadct.
• get / profile – Examine lines or columns.
• get / cursor – Examine pixel values. If image format is FITS, PDS, or SAD and if the
header contains astrometric information, then pixel position in the sky is given (R.A. and
Dec.).
• plot / histo – Plot the histogram.
• plot / contours –Invokexcontour.
• plot / 3d visu – Invoke interactive widget to display a surface plot.
• plot / load .. – copy image to an ordinary IDL window.
• info – Print the min, max, mean, sigma of the image
• fft – Computes the Fourier transform and display either the power spectrum, the phase,
the real part or the imaginary part.
• pan – Pan the image. The zoom factor can be 2, 4, 8, 1/2, 1/4, 1/8.
• ROI / select – Interactively select a region of the displayed image.
• ROI / save – Save the selected region as as a FITS file.