lvrotate(3)

LIBRARY ROUTINE
lvrotate - Rotate an image by an arbitrary angle

LIBRARY CALL
#include "vinclude.h"
int
lvrotate(image,ang,xc,yc)
struct xvimage *image;
float  ang;
int xc, yc;

INPUT

image
    pointer to xvimage structure to be processed

ang angle in degrees to rotate by, positive is clockwise (float)

xc  X coordinate of center of rotation (float)

yc  Y coordinate of center of rotation (float)

OUTPUT

image
    holds the result of the operation. The output data type is the same as the input data type.

Return Value:
    1 on success, 0 on failure.

MODIFICATIONS

Scott Wilson 18-Sep-90 Added multiband support

Scott Wilson 25-Aug-91 Fixed bad type conversion on rotation angle.

DESCRIPTION
lvrotate rotates an image by a specfied angle, about a specified point. The rotation is performed using bilinear interpolation. Portions of the output image that do not have a corresponding pixel in the input image are set to zero.

Note that image is used for both the input xvimage structure and the resulting output xvimage structure. This is done to save space, but you must be careful not to overwrite important data.

SEE ALSO
vrotate(1), intro(3), vipl(3), verror(3), vutils(3) lvresize(1), lvwarp(1), lvshrink(1), lvexpand(1)

RESTRICTIONS
lvrotate does not work on BIT or COMPLEX data types. lvrotate does not work on explicit location data.

AUTHOR
Scott Wilson

COPYRIGHT
Copyright 1991, University of New Mexico. All rights reserved.