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imagecolorresolvealpha

imagecolorresolvealpha

(PHP 4 >= 4.0.6, PHP 5, PHP 7)

imagecolorresolvealpha — Get the index of the specified color + alpha or its closest possible alternative

Description

int imagecolorresolvealpha ( resource $image , int $red , int $green , int $blue , int $alpha )

This function is guaranteed to return a color index for a requested color, either the exact color or the closest possible alternative.

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.

alpha

A value between 0 and 127. 0 indicates completely opaque while 127 indicates completely transparent.

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

Return Values

Returns a color index.

Examples

Example #1 Using imagecoloresolvealpha() to get colors from an image

<?php // Load an image $im = imagecreatefromgif('phplogo.gif' // Get closest colors from the image $colors = array( $colors[] = imagecolorresolvealpha($im, 255, 255, 255, 0 $colors[] = imagecolorresolvealpha($im, 0, 0, 200, 127 // Output print_r($colors imagedestroy($im ?>

The above example will output something similar to:

Array ( [0] => 89 [1] => 85 )

See Also

  • imagecolorclosestalpha() - Get the index of the closest color to the specified color + alpha

← imagecolorresolve

imagecolorset →

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Licensed under the Creative Commons Attribution License v3.0 or later.

https://secure.php.net/manual/en/function.imagecolorresolvealpha.php