php pngquant

PNGQuant is a command-line utility and a PHP library for lossy compression of PNG images. It reduces the number of colors in an image while maintaining a visually similar appearance. PNGQuant uses a modified version of the K-means algorithm to select the optimal color palette for the image.

To use PNGQuant in PHP, you can either execute the PNGQuant command-line utility using the exec() function or use the PHP library provided by PNGQuant.

Here's an example of using PNGQuant in PHP with the command-line utility:

$imagePath = '/path/to/image.png';
$outputPath = '/path/to/output.png';

$command = 'pngquant --force --output ' . $outputPath . ' ' . $imagePath;
exec($command, $output, $returnCode);

if ($returnCode === 0) {
    echo 'Image compressed successfully!';
} else {
    echo 'Error compressing image: ' . implode("\n", $output);
}

And here's an example of using PNGQuant in PHP with the PHP library:

require 'path/to/pngquant.php';

$imagePath = '/path/to/image.png';
$outputPath = '/path/to/output.png';

$pngquant = new PNGQuant();
$pngquant->setQuality(80); // Set the compression quality (0-100)
$pngquant->setImage($imagePath);
$pngquant->setOutput($outputPath);
$pngquant->execute();

if ($pngquant->getReturnCode() === 0) {
    echo 'Image compressed successfully!';
} else {
    echo 'Error compressing image: ' . $pngquant->getOutput();
}

Note that you need to have PNGQuant installed on your server for the above examples to work. You can find PNGQuant and installation instructions on its official GitHub repository: https://github.com/kornelski/pngquant