imagefilter

(PHP 5)

imagefilter -- Applies a filter to an image

Описание

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

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

Список параметров

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

Возвращаемые значения

Возвращает TRUE в случае успешного завершения или FALSE в случае возникновения ошибки.

Примеры

Пример 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);
?>

Пример 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);
?>

Пример 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);
?>

Примечания

Замечание: Эта функция доступна только в том случае, если PHP был скомпилирован со встроенной библиотекой GD.

Смотрите также

imageconvolution()