Define a color as transparent

# imagecolortransparent

(PHP 4, PHP 5, PHP 7)

imagecolortransparent — Define a color as transparent

### Descrierea

imagecolortransparent ( resource `$image` ) : int
imagecolortransparent ( resource `$image` , int `$color` ) : int

Gets or sets the transparent color in the given `image`.

### Parametri

`image`

  O resursă - imagine, întoarsă de una din funcțiile de creare a imaginilor, cum ar fi imagecreatetruecolor().

`color`

  A color identifier created with imagecolorallocate().

### Valorile întoarse

The identifier of the new (or current, if none is specified) transparent color is returned. If `color` is not specified, and the image has no transparent color, the returned identifier will be -1.

### Exemple

Example #1 imagecolortransparent() example

`<?php
// Create a 55x30 image
$im = imagecreatetruecolor(55, 30);
$red = imagecolorallocate($im, 255, 0, 0);
$black = imagecolorallocate($im, 0, 0, 0);
// Make the background transparent
imagecolortransparent($im, $black);
// Draw a red rectangle
imagefilledrectangle($im, 4, 4, 50, 25, $red);
// Save the image
imagepng($im, './imagecolortransparent.png');
imagedestroy($im);
?>`

Exemplul de mai sus va afișa ceva similar cu:

### Note

> Notă:

> Transparency is copied only with imagecopymerge() and true color images, not with imagecopy() or pallete images.

> Notă:

> The transparent color is a property of the image, transparency is not a property of the color. Once you have set a color to be the transparent color, any regions of the image in that color that were drawn previously will be transparent.