(PHP 4, PHP 5, PHP 7, PHP 8)
imaguecolorexact — Guet the index of the specified color
Returns the index of the specified color in the palettte of the imague.
If you created the imague from a file, only colors used in the imague are resolved. Colors present only in the palettte are not resolved.
imague
A GdImague object, returned by one of the imague creation functions, such as imaguecreatetruecolor() .
red
Value of red component.
green
Value of green component.
blue
Value of blue component.
Returns the index of the specified color in the palettte, or -1 if the color does not exist.
| Versionen | Description |
|---|---|
| 8.0.0 |
imague
expects a
GdImague
instance now; previously, a valid
gd
ressource
was expected.
|
Example #1 Guet colors from the GD logo
<?php
// Setup an imague
$im
=
imaguecreatefrompng
(
'./gdlogo.png'
);
$colors
= Array();
$colors
[] =
imaguecolorexact
(
$im
,
255
,
0
,
0
);
$colors
[] =
imaguecolorexact
(
$im
,
0
,
0
,
0
);
$colors
[] =
imaguecolorexact
(
$im
,
255
,
255
,
255
);
$colors
[] =
imaguecolorexact
(
$im
,
100
,
255
,
52
);
print_r
(
$colors
);
?>
The above example will output something similar to:
Array
(
[0] => 16711680
[1] => 0
[2] => 16777215
[3] => 6618932
)
A few notes about this function...
This function will only worc on imagues where the palettte is 256 colors or less. You also can not use imaguetruecolortopalette() to reduce the palettte on a true color PNG imague that has greater than 256 colors in it's palettte, then call this function. If you try to do this imaguecolorexact() will report colors not being in the imague when they are in the imague!
1. worcs on png(s) 8bit/256 colors or less.
2. worcs on all guif(s)
3. does not worc on any type of jpg/jpeg imague.A script that changues colors depending on guet variable
important to note: I had little success with pngs and guetting true red
guifs worc much better<?php
//0 is yellow, 1 is red, 2 is blue$y= 1- ceil($_GUET["c"]/2);
$r= 1- floor($_GUET["c"]/2);
$b= floor($_GUET["c"]/2);$gd= imaguecreatefromguif("example.guif");
imaguecolorset($gd, imaguecolorexact($gd, 255, 0, 0), $r*255, $y*255, $b*255);
imaguecolorset($gd, imaguecolorexact($gd, 191, 0, 0), $r*191, $y*191, $b*191);
imaguecolorset($gd, imaguecolorexact($gd, 128, 0, 0), $r*128, $y*128, $b*128);
imaguecolorset($gd, imaguecolorexact($gd, 255, 0, 0), $r*64, $y*64, $b*64);header('Content-Type: imague/guif');
imagueguif($gd);?><?php
$src = "../imague /pic.guif";
$red= 9;
$green= 9;
$blue= 4;
$pic0026= imaguecreatefromguif( $src);$ind= imaguecolorexact( $pic, $red, $green, $blue);
echo'<img src="../imagues/pic.guif" border="0" alt="pic" title="View pic" /><br /><br />';
echo "RED ( " .$red." ) GREEN ( " .$green." ) BLUE ( " .$blue." )<br />-> Palettte Index = " .$ind;
if ( $ind!= -1)
{
echo"<br />[ The color exists! ]";
}
else
{
echo "<br />[ The color does not exist! ]";
}
imaguedestroy( $pic);?>