imagecolorsforindex
This code shows the palettes for all .gif files in the current working directory. (Output is HTML.)
<?php
print '<pre>';
foreach(glob('*.gif') as $src_fn)
{
$im2 = ImageCreateFromGif($src_fn);
echo '<a href="',htmlspecialchars($src_fn),'">';
print sprintf('%-30s', $src_fn);
echo '</a>';
$cc = ImageColorsTotal($im2);
for($n=0; $n<$cc; ++$n)
{
$c = ImageColorsForIndex($im2, $n);
print
sprintf('<span style="background:#%02X%02X%02X"> </span>',
$c['red'], $c['green'], $c['blue']);
}
ImageDestroy($im2);
print "\n";
}
print '</pre>';
?>
imagecolorstotal
(PHP 4, PHP 5)
imagecolorstotal — Find out the number of colors in an image's palette
Description
int imagecolorstotal
( resource
$image
)Returns the number of colors in an image palette.
Parameters
-
image -
An image resource, returned by one of the image creation functions, such as imagecreatefromgif().
Return Values
Returns the number of colors in the specified image's palette or 0 for truecolor images.
Examples
Example #1 Getting total number of colors in an image using imagecolorstotal()
<?php
// Create image instance
$im = imagecreatefromgif('php.gif');
echo 'Total colors in image: ' . imagecolorstotal($im);
// Free image
imagedestroy($im);
?>
The above example will output something similar to:
Total colors in image: 128
See Also
- imagecolorat() - Get the index of the color of a pixel
- imagecolorsforindex() - Get the colors for an index
- imageistruecolor() - Finds whether an image is a truecolor image
add a note
User Contributed Notes
imagecolorstotal - [2 notes]
bisqwit at iki dot fi ¶
6 years ago
black-eye at web dot de ¶
9 years ago
I created a function to count the colors in a .gif file automatically. Works perfect on Win2k Servers
<?PHP
function bildinfo($bild)
{
/*
******* FUNCTION BILDINFO() ******* ******* ******* *******
******* ******* ******* ******* ******* ******* ******* *******
******* Copyright 2003 by www.BLACKEYE.org ******* *******
******* ******* ******* ******* ******* ******* ******* *******
Please don't change the copyright in this file. You can modify
this file, but NEVER remove the copyright !
If YOU were the creator of this function, you would say the
same, eh ? :)
For more informations / How to use:
HOMEPAGE: www.blackeye.org
******* ******* ******* ******* ******* ******* ******* *******
*/
$fp = fopen($bild, "rb"); // Open image in binary mode (for windows)
$f = fread($fp, filesize($bild));
$c = bin2hex($f); // Binary file -> Hex
$c = ereg_replace("5c30", "0000", $c); // In gif-files "5c30" stands for real "00" values. why ? i dont know
$b = $c;
$pos = strpos($c, "fe0102"); // 6 Byte termination for the color table
if ($pos > 0)
{
$c = substr($c, 26);
$c = substr($c, 0, strpos($c, "fe0102")); // Termination for the color table of non-transparent images
}
else
{
$c = substr($c, 26);
$c = substr($c, 0, strpos($c, "21f904")); // Termination for the color table
}
echo "<table border='0'>";
$i = 0;
$y = 0;
$str = "";
$pix = chunk_split($c, 6, ";"); // 6 Char long block (color)
$pix = explode(";",$pix);
sort($pix);
foreach($pix as $col)
{
if ($col && !ereg($col.";", $str) && strlen($col) == 6) // So that no color is twice in the list
{
$str .= $col.";";
$i++; // Für die Table anzeige
$y++; // Anzahl Farben
if ($i == 1) { echo ""; }
echo "<td width='6' height='8' bgcolor='#$col' style='border:1px solid #000000;font-size:1px;' title='©2003 by www.BLACKEYE.org'>";
echo " ";
echo "</td>";
if ($i == 10)
{
echo ""; $i = 0;
}
}
}
echo "</table>";
echo $y." visible colors";
}
$bild = ""; // Imagefile
bildinfo($bild);
?>
Only copy & paste this text into your .php file, where you want to show the image.