(PHP 5 >= 5.5.0, PHP 7, PHP 8)
imagesetinterpolation — Set the interpolation method
Sets the interpolation method, setting an interpolation method affects the rendering of various functions in GD, such as the imagerotate() function.
image
A GdImage object, returned by one of the image creation functions, such as imagecreatetruecolor().
method
The interpolation method, which can be one of the following:
IMG_BELL
: Bell filter. IMG_BESSEL
: Bessel filter. IMG_BICUBIC
: Bicubic interpolation. IMG_BICUBIC_FIXED
: Fixed point implementation of the bicubic interpolation. IMG_BILINEAR_FIXED
: Fixed point implementation of the bilinear interpolation (default (also on image creation)
). IMG_BLACKMAN
: Blackman window function. IMG_BOX
: Box blur filter. IMG_BSPLINE
: Spline interpolation. IMG_CATMULLROM
: Cubic Hermite spline interpolation. IMG_GAUSSIAN
: Gaussian function. IMG_GENERALIZED_CUBIC
: Generalized cubic spline fractal interpolation. IMG_HERMITE
: Hermite interpolation. IMG_HAMMING
: Hamming filter. IMG_HANNING
: Hanning filter. IMG_MITCHELL
: Mitchell filter. IMG_POWER
: Power interpolation. IMG_QUADRATIC
: Inverse quadratic interpolation. IMG_SINC
: Sinc function. IMG_NEAREST_NEIGHBOUR
: Nearest neighbour interpolation. IMG_WEIGHTED4
: Weighting filter. IMG_TRIANGLE
: Triangle interpolation. Version | Description |
---|---|
8.0.0 | image expects a GdImage instance now; previously, a valid gd resource was expected. |
Example #1 imagesetinterpolation() example
<?php
// Load an image
$im = imagecreate(500, 500);
// By default interpolation is IMG_BILINEAR_FIXED, switch
// to use the 'Mitchell' filter:
imagesetinterpolation($im, IMG_MITCHELL);
// Continue to work with $im ...
?>
Changing the interpolation method affects the following functions when rendering: