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图像 | Image

imagecolorexact

imagecolorexact

(PHP 4, PHP 5, PHP 7)

imagecolorexact — Get the index of the specified color

Description

int imagecolorexact ( resource $image , int $red , int $green , int $blue )

Returns the index of the specified color in the palette of the image.

If you created the image from a file, only colors used in the image are resolved. Colors present only in the palette are not resolved.

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.

Return Values

Returns the index of the specified color in the palette, or -1 if the color does not exist.

Examples

Example #1 Get colors from the GD logo

<?php // Setup an image $im = imagecreatefrompng('./gdlogo.png' $colors   = Array( $colors[] = imagecolorexact($im, 255, 0, 0 $colors[] = imagecolorexact($im, 0, 0, 0 $colors[] = imagecolorexact($im, 255, 255, 255 $colors[] = imagecolorexact($im, 100, 255, 52 print_r($colors // Free from memory imagedestroy($im ?>

The above example will output something similar to:

Array ( [0] => 16711680 [1] => 0 [2] => 16777215 [3] => 6618932 )

See Also

  • imagecolorclosest() - Get the index of the closest color to the specified color

← imagecolordeallocate

imagecolorexactalpha →

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

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