1IM_AFFINE(3)               Library Functions Manual               IM_AFFINE(3)
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NAME

6       im_affine - apply an affine transform to an image
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SYNOPSIS

9       #include <vips/vips.h>
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11       int im_affine(in, out, a, b, c, d, dx, dy, x, y, w, h)
12       IMAGE *in, *out;
13       double a, b, c, d, dx, dy;
14       int x, y;
15       int w, h;
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DESCRIPTION

19       im_affine()  applies  an affine transformation on the image held by the
20       IMAGE descriptor in and puts the result at the location pointed by  the
21       IMAGE  descriptor  out.  in many have any number of bands, be any size,
22       and have any non-complex type.
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24       The transformation is described by a, b, c, d, dx, dy.  The point (x,y)
25       in the input is mapped onto point (X,Y) in the output by
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27         X = a * x + b * y + dx
28         Y = c * x + d * y + dy
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30       The area of the output image given by w, h, x, y is generated. (0,0) is
31       the position of the  transformed  top-left-hand  corner  of  the  input
32       image.  Function im_affine resamples the transformed image using bilin‐
33       ear interpolation.
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RETURN VALUE

37       The functions return 0 on success and -1 on error.
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BUGS

40       As with most resamplers, im_affine(3) performs poorly at the  edges  of
41       images.
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SEE ALSO

44       im_similarity(3)
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48                               21 December 1999                   IM_AFFINE(3)