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0.1.63 imview

Requires:

Synopsis
View an image

Description

The imview task will display images in raster, contour, vector or marker form. Images can be blinked, and movies are available for spectral-line image cubes.

Executing the imview task will bring up a display panel window, which can be resized. If no data file was specified, a Load Data window will also appear. Click on the desired data file and choose the display type; the rendered data should appear on the display panel.

A Data Display Options window will also appear. It has drop-down subsections for related options, most of which are self-explanatory.

The state of the imview task – loaded data and related display options – can be saved in a ’restore’ file for later use. You can provide the restore filename on the command line or select it from the Load Data window.

It is possible to use the viewer GUI tool to perform image manipulation and analysis tasks that are not available from the command-line start.

Arguments





Inputs

raster

(Optional) Raster filename (string) or complete raster config dictionary. The allowed dictionary keys are file (string), scaling (numeric), range (2 element numeric vector), colormap (string), and colorwedge (bool).

allowed:

any

Default:

variant

contour

(Optional) Contour filename (string) or complete contour config dictionary. The allowed dictionary keys are file (string), levels (numeric vector), unit (float), and base (float).

allowed:

any

Default:

variant

zoom

(Optional) zoom can specify intermental zoom (integer), zoom region read from a file (string) or dictionary specifying the zoom region. The dictionary can have two forms. It can be either a simple region specified with blc (2 element vector) and trc (2 element vector) [along with an optional coord key (”pixel” or ”world”; pixel is the default) or a complete region rectangle e.g. loaded with ”rg.fromfiletorecord( )”. The dictionary can also contain a channel (integer) field which indicates which channel should be displayed.

allowed:

any

Default:

variant 1

axes

(Optional) this can either be a three element vector (string) where each element describes what should be found on each of the x, y, and z axes or a dictionary containing fields ”x”, ”y” and ”z” (string).

allowed:

any

Default:

variant

out

(Optional) Output filename or complete output config dictionary. If a string is passed, the file extension is used to determine the output type (jpg, pdf, eps, ps, png, xbm, xpm, or ppm). If a dictionary is passed, it can contain the fields, file (string), scale (float), dpi (int), or orient (landscape or portrait). The scale field is used for the bitmap formats (i.e. not ps or pdf) and the dpi parameter is used for scalable formats (pdf or ps).

allowed:

any

Default:

variant

Returns
void

Example

 
The imview task provides access to a subset of all of the configuration  
options for loading and configuring the display of images in the casaviewer.  
This interface will evolve and eventually provide access to nearly all of  
        the image options available in the casaviewer.  
 
To simply create a casaviewer to set up interactively, you can use:  
 
    imview  
 
To open a particular image:  
 
    imview "ngc5921.clean.image"  
 
        to open an image and overlay a contour:  
 
    imview "ngc5921.clean.image", "ngc5921.clean.image"  
 
or equivalently:  
 
            imview( raster="ngc5921.clean.image", contour="ngc5921.clean.image" )  
 
to output an image:  
 
            imview( raster="ngc5921.clean.image", out="ngc5921-01.png" )  
 
 
There are five optional parameters for imview -- raster, contour, zoom,  
axes, and out. Each of these parameters can take a few different forms and  
are treated as python dictionaries:  
 
raster  -- (string) image file to open  
           (dict)   file (string)     => image file to open  
                    scaling (float)   => scaling power cycles  
                    range (float*2)   => data range  
                    colormap (string) => name of colormap  
                    colorwedge (bool) => show color wedge?  
contour -- (string) file to load as a contour  
           (dict)   file (string)     => file to load  
                    levels (float*N)  => relative levels  
                    base (numeric)    => zero in relative levels  
                    unit (numeric)    => one in the relative levels  
zoom    -- (int)    integral zoom level  
           (string) region file to load as the zoom region  
           (dict)   blc (numeric*2)   => bottom left corner  
                    trc (numeric*2)   => top right corner  
                    coord (string)    => pixel or world  
                    channel (int)     => chanel to display  
           (dict)   <region record>   => record loaded  
                                         e.g. rg.fromfiletorecord( )  
axes    -- (string*3) demension to display on the x, y, and z axes  
           (dict)     x               => dimension for x-axes  
                      y               => dimension for y-axes  
                      z               => dimension for z-axes  
out     -- (string) file with a supported extension  
                    [jpg, pdf, eps, ps, png, xbm, xpm, ppm]  
            (dict)    file (string)   => filename  
                      format (string) => valid ext (filename ext overrides)  
                      scale (numeric) => scale for non-eps, non-ps output  
                      dpi (numeric)   => dpi for eps or ps output  
                      orient (string) => portrait or landscape  
 
        Examples:  
 
1)  A subset (zoom) of a raster image. Note the notation of curly brackets:  
 
    imview(raster="ngc5921.clean.image", out="ngc5921-02.png",  
           zoom={’channel’: 10, ’blc’: [113,109], ’trc’: [141,136]} )  
 
 
2) An overlay of a raster image, ngc5921.clean.image, with a  
contour map of the same image ngc5921.clean.image. Data ranges  
are selected, as well as the colormap and the scaling cycles  
of the raster image. Contours are autogenerated and The x-axis  
will be Declination. The image is written out to a file named  
        myout.png in the png format.  
 
imview(raster={’file’: ’ngc5921.clean.image’,  
               ’range’: [-0.01,0.03],  
               ’colormap’: ’Hot Metal 2’,  
               ’scaling’: -1},  
       contour={’file’: ’ngc5921.clean.image’},  
       axes={’x’:’Declination’} ,  
       zoom={’channel’: 7, ’blc’: [75,75], ’trc’: [175,175],  
             ’coord’: ’pixel’},  
       out=’myout.png’)  
 
3) As example (2) but with an integral zoom level and no output to a file  
 
imview(raster={’file’: ’ngc5921.clean.image’,  
               ’range’: [-0.01,0.03],  
               ’colormap’: ’Hot Metal 2’},  
       contour={’file’: ’ngc5921.clean.image’},  
       axes={’x’:’Declination’} ,  
       zoom=2)  
 
4) Now, the contour levels are explicitely given, a region file is used  
to define the zoom area  
 
imview(raster={’file’: ’ngc5921.clean.image’,  
               ’range’: [-0.01,0.03],  
               ’colormap’: ’Hot Metal 2’},  
       contour={’file’: ’ngc5921.clean.image’,  
                ’levels’: [-0.2, 0.2, 0.25, 0.3, 0.35, 0.4, 0.6, 0.8] },  
       zoom=’myregion.rgn’)  
 
specifying "zoom={’file’: ’myregion.rgn’, ’channel’: 10}" would result  
in the same level of zoom and would display channel number 10 from  
the cube.  
 
 


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