For example, set TRUE to 1 to display an image that is pixel interleaved and has dimensions of (3, m, n). The image parameter must have three dimensions, one of which must be equal to three. The value assigned to TRUE specifies the index of the dimension over which color is interleaved. Set this keyword to a nonzero value to indicate that a TrueColor (16-, 24-, or 32-bit) image is to be displayed. If set, the image is drawn from the top down instead of the normal bottom up. If specified, ORDER overrides the current setting of the !ORDER system variable for the current image only. This system is useful when dealing with devices, such as PostScript printers, that do not provide a direct relationship between image pixels and the size of the resulting image. Set this keyword to indicate that all position and size values are given in inches from the origin. Set this keyword to indicate that the X, Y, Xsize, Ysize, and Z arguments are given in centimeters from the origin. The Channel argument is identical to the CHANNEL graphics keyword. This parameter is ignored on display systems that have only one memory channel. It is assumed to be zero if not specified. CHANNEL specifies the memory channel to be written. Some image display devices are capable of storing more than a single image or can combine three single color images to form a TrueColor image.
Note: When using a device with scalable pixels (e.g., PostScript), the XSIZE and YSIZE keywords should also be used. If a position number is used instead of X and Y, the position of the image is calculated from the dimensions of the image as follows (integer arithmetic is used).įor example, when displaying 128 by 128 images on a 512 by 512 display, the position numbers run from 0 to 15 as follows: Image positions run from the top left of the screen to the bottom right. PositionĪn integer specifying the position for Image within the graphics window. If X and Y are present, they specify the lower-left coordinate of the displayed image, relative to the lower-left corner of the screen. If this argument is not already of byte type, it is converted prior to use. Graphics Keywords: Arguments ImageĪ vector or two-dimensional, or three-dimensional array to be displayed as an image. The optional parameters can be used to specify the screen position of the image in a variety of ways. If no optional parameters are present, IMAGE is output to the display with its lower-left corner at coordinate (0, 0). In addition, for displays with less than 256 colors, elements of the input image with values between !D.TABLE_SIZE and 255 will be displayed using the color index !D.TABLE_SIZE-1. Values outside the range are “wrapped” during the conversion.
While the TV procedure does not scale the intensity of an image, it does convert the input image data to byte type. To display a TrueColor image (an image with 16, 24, or 32 bits per pixel) you must use the TRUE keyword. RGB images are displayed with the TV procedure.
The TVSCL procedure displays an image scaled to range from 0 up to 255 depending on the colors available to IDL. Note: The TV procedure displays an image in its original form. To display an image with scaling, use the TVSCL procedure. The TV procedure displays images in a Direct Graphics window without scaling the intensity. Note: Please see the IMAGE function, which replicates the functionality of this routine and offers an interactive interface. Syntax | Arguments | Keywords | Examples | Version History | See Also Routines (alphabetical) > Routines: T > TV Procedure TV Procedure