A vector or two-dimensional matrix to be displayed as an image.If image is not already of byte type, it is converted prior to use, although the conversion may distort the data contained in the image.
Displays images without scaling the intensity.
TV, image [, position]
A vector or two-dimensional matrix to be displayed as an image.If image is not already of byte type, it is converted prior to use, although the conversion may distort the data contained in the image.
NOTE: To insure data integrity, use the TVSCL procedure instead of TV. TVSCL does a byte scaling before displaying the image.
(optional) The lower-left x- and y-coordinates of the displayed image.channel
(optional) The memory channel to be written. If not specified, it is assumed to be zero. This parameter is ignored on display systems that have only one memory channel.position
(optional) A number specifying the position of the image. Positions run from the left of the window to the right, and from the top of the window to the bottom (see the Discussion section for details).
If present, specifies that all position values (the x y parameters and the XSize and YSize keywords) are in centimeters from the origin. This is useful when dealing with devices that do not provide a direct relationship between image pixels and the size of the resulting image, such as PostScript printers.If Centimeters is not present, position values are taken to be in device coordinates.
Channel
The memory channel to be written. This keyword is identical to the channel input parameter; only one needs to be used.Data
If present, specifies that all position and size values are in data coordinates. This is useful when drawing an image over an existing plot, since the plot establishes the data scaling.Device
If present, specifies that all position and size values are in device coordinates. This is the default.Inches
If present, specifies that all position and size values are in inches from the origin. This is useful when dealing with devices that do not provide a direct relationship between image pixels and the size of the resulting image, such as PostScript printers.Normal
If present, specifies that all position and size values are in normalized coordinates in the range 0.0 to 1.0. This is useful when you want to draw an image in a device-independent manner.Order
If specified, overrides the current setting of the !Order system variable for the current image only. If nonzero, Order causes the image to be drawn from the top-down, instead of from the bottom-up (the default).True
(UNIX/OpenVMS Only) If present and nonzero, indicates that a true-color (24-bit) image is to be displayed and specifies the index of the dimension over which color is interleaved:
NOTE: To use True, the image parameter must have three dimensions, one of which is equal to 3.
The width of the resulting image. This keyword is intended for devices with scalable pixel size (such as PostScript), and is ignored by pixel-based devices that are unable to change the size of their pixels.YSize
The height of the resulting image, with the same limitations as XSize.Z
The z position. The value of z is of use only if the three-dimensional transformation is in effect via the T3d keyword.
Windows Users: Because Windows NT reserves 20 out of the available 256 colors, you might achieve better results displaying color images with the TVSCL procedure. TVSCL automatically scales the color intensities to the full range of available colors.
The starting x-coordinate position is defined as:
xdim and ydim are the dimensions of the array,
mandril = BYTARR(512, 512) OPENR, unit, !Data_dir + 'mandril.img', /Get_lun READU, unit, mandril FREE_LUN, unit
WINDOW, XSize=512, YSize=512 TV, mandril
TV, mandril, /Order
small_img = CONGRID(mandril, 100, 100)
CONTOUR, small_img TV, small_img, 0, 0, /Data
FOR i=0, 24 DO TV, small_img, i
data = BYTSCL(DIST(60))
TV, data
LOADCT, 5
enlarge = REBIN(data, 480, 480)
TV, enlarge
enlarge = REBIN(data, 480, 480, /Sample) TV, enlarge
enlarge = CONGRID(data, 480, 480) TV, enlarge
enlarge = CONGRID(data, 480, 480, /Interp) TV, enlarge
For more information, see Image Display Routines: TV and TVSCL in Chapter 6 of the PV-WAVE User's Guide.
