View an image
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.
1.8.0