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GD and Image Functions
PHP Manual

# imagecolorallocate

(PHP 4, PHP 5, PHP 7)

imagecolorallocate — Allocate a color for an image

### Description

int imagecolorallocate ( resource `$image` , int `$red` , int `$green` , int `$blue` )

Returns a color identifier representing the color composed of the given RGB components.

imagecolorallocate() must be called to create each color that is to be used in the image represented by `image`.

> Note:

> The first call to imagecolorallocate() fills the background color in palette-based images - images created using imagecreate().

### Parameters

`image`

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

`red`

  Value of red component.

`green`

  Value of green component.

`blue`

  Value of blue component.

These parameters are integers between 0 and 255 or hexadecimals between 0x00 and 0xFF.

### Return Values

A color identifier or `FALSE` if the allocation failed.

Warning

This function may return Boolean `FALSE`, but may also return a non-Boolean value which evaluates to `FALSE`. Please read the section on Booleans for more information. Use the === operator for testing the return value of this function.

### Changelog

Version | Description
--- | ---
5.1.3 | Returns `FALSE` if the allocation failed. Previously -1 was returned.

### Examples

Example #1 imagecolorallocate() example

`<?php
$im = imagecreate(100, 100);
// sets background to red
$background = imagecolorallocate($im, 255, 0, 0);
// sets some colors
$white = imagecolorallocate($im, 255, 255, 255);
$black = imagecolorallocate($im, 0, 0, 0);
// hexadecimal way
$white = imagecolorallocate($im, 0xFF, 0xFF, 0xFF);
$black = imagecolorallocate($im, 0x00, 0x00, 0x00);
?>`

### See Also

- imagecolorallocatealpha() - Allocate a color for an image
- imagecolordeallocate() - De-allocate a color for an image

imagecharup
imagecolorallocatealpha
GD and Image Functions
PHP Manual