PHP | imagetruecolortopalette() Function

Last Updated : 11 Jul, 2025

The imagetruecolortopalette() function is an inbuilt function in PHP which is used to convert a true color image to a palette image. Syntax:

bool imagetruecolortopalette( $image, $dither, $ncolors )

Parameters: This function accepts three parameters as mentioned above and described below:

$image: It is returned by one of the image creation functions, such as imagecreatetruecolor(). It is used to create size of image.
$dither: It is the boolean value which indicate the image is dither. If it is True then dithering will be used which will result in a more speckled image but with better color approximation.
$ncolors: This parameter contains the set of maximum number of colors that should be retained in the palette.

Return Value: This function returns True on success or False on failure. Below programs illustrates the imagetruecolortopalette() function in PHP: Program 1:

php

<?php

// Create a 400*300 image
$im = imagecreatetruecolor(400, 300);

// Set the background color of image 
$background_color = imagecolorallocate($im,  0, 153, 0); 
     
// Fill background with above selected color 
imagefill($im, 0, 0, $background_color); 

// Convert to palette-based with no dithering and 255 colors
imagetruecolortopalette($im, true, 255);

// Output the picture to the browser 
header('Content-type: image/png'); 
     
imagepng($im); 
?>

Output:

Program 2:

php

<?php

// Setup the true color and palette images 
$im = imagecreatefrompng( 
'https://media.geeksforgeeks.org/wp-content/uploads/geeksforgeeks-9.png'); 

// Convert to palette-based with no dithering and 255 colors
imagetruecolortopalette($im, false, 255);

// Output the picture to the browser 
header('Content-type: image/png'); 
     
imagepng($im); 
?>