Forum und email
imagefilter

imagefilter

(PHP 5)

imagefilter -- Applies a filter to an image

Popis

bool imagefilter ( resource image, int filtertype [, int arg1 [, int arg2 [, int arg3]]] )

imagefilter() applies the given filter filtertype on the image.

Seznam parametrů

image

An image resource, returned by one of the image creation functions, such as imagecreatetruecolor().

filtertype

filtertype can be one of the following:

  • IMG_FILTER_NEGATE: Reverses all colors of the image.

  • IMG_FILTER_GRAYSCALE: Converts the image into grayscale.

  • IMG_FILTER_BRIGHTNESS: Changes the brightness of the image. Use arg1 to set the level of brightness.

  • IMG_FILTER_CONTRAST: Changes the contrast of the image. Use arg1 to set the level of contrast.

  • IMG_FILTER_COLORIZE: Like IMG_FILTER_GRAYSCALE, except you can specify the color. Use arg1, arg2 and arg3 in the form of red, blue, green. The range for each color is 0 to 255.

  • IMG_FILTER_EDGEDETECT: Uses edge detection to highlight the edges in the image.

  • IMG_FILTER_EMBOSS: Embosses the image.

  • IMG_FILTER_GAUSSIAN_BLUR: Blurs the image using the Gaussian method.

  • IMG_FILTER_SELECTIVE_BLUR: Blurs the image.

  • IMG_FILTER_MEAN_REMOVAL: Uses mean removal to achieve a "sketchy" effect.

  • IMG_FILTER_SMOOTH: Makes the image smoother. Use arg1 to set the level of smoothness.

arg1

arg2

arg3

Návratové hodnoty

Vrací TRUE při úspěchu, FALSE při selhání.

Příklady

Příklad 1. imagefilter() grayscale example

<?php
$im
= imagecreatefrompng('dave.png');
if (
$im && imagefilter($im, IMG_FILTER_GRAYSCALE)) {
    echo
'Image converted to grayscale.';
    
imagepng($im, 'dave.png');
} else {
    echo
'Conversion to grayscale failed.';
}

imagedestroy($im);
?>

Příklad 2. imagefilter() brightness example

<?php
$im
= imagecreatefrompng('sean.png');
if (
$im && imagefilter($im, IMG_FILTER_BRIGHTNESS, 20)) {
    echo
'Image brightness changed.';
    
imagepng($im, 'sean.png');
} else {
    echo
'Image brightness change failed.';
}

imagedestroy($im);
?>

Příklad 3. imagefilter() colorize example

<?php
$im
= imagecreatefrompng('philip.png');

/* R, G, B, so 0, 255, 0 is green */
if ($im && imagefilter($im, IMG_FILTER_COLORIZE, 0, 255, 0)) {
    echo
'Image successfully shaded green.';
    
imagepng($im, 'philip.png');
} else {
    echo
'Green shading failed.';
}

imagedestroy($im);
?>

Poznámky

Poznámka: Tato funce je k dispozici jen tehdy, bylo-li PHP zkompilováno s přibalenou verzí knihovny GD.