ROT_INT Function
Standard Library function that rotates and magnifies (or demagnifies) an image on the display screen.
Usage
result = ROT_INT(image, ang[, mag, xctr, yctr])
Input Parameters
image—The input image to be manipulated. Can be of any data type except string. Must be two-dimensional.
ang—The angle of rotation in degrees clockwise.
mag—(optional) Magnification or demagnification factor (see Discussion).
xctr—(optional) The x subscript of the center of rotation. If omitted, xctr is equal to the number of columns in image divided by 2.
yctr—(optional) The y subscript of the center of rotation. If omitted, yctr is equal to the number of rows in image divided by 2.
Returned Value
result—A rotated and magnified (or demagnified) image. The dimensions are the same as those for the input image.
Keywords
None.
Discussion
ROT_INT calls the function POLY_2D to rotate and scale the input image.
The magnification factor can be of integer or floating-point data type. It is specified as follows (with 1 being the default value):
mag = 1—no change
mag > 1—causes magnification
mag < 1—causes demagnification
For example, if mag is set to 0.5, this would result in an image half the size of the original image, and if mag is set to 3, this would result in an image three times the size of the original.
ROT_INT uses the bilinear interpolation method to rotate and scale the input image.
note | If a faster (but less accurate) method of interpolation is needed, use the related function ROT, which uses a nearest neighbor method. |
See Also
For information on interpolation methods, see the PV‑WAVE User’s Guide.
Version 2017.1
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