sgi/CIDIT/include/ConversorWebp.php

<?php

class ConversorWep {
    public static function generaImagenWebp($file, $compression_quality = 80) {
        $temp = explode('.', $file);
        $output_file = 'imgConvert/convertidas/' . $temp[0] . '.webp';
        $file = 'imgConvert/originales/' . $file;
        // check if file exists
        if (!file_exists($file)) {
            return false;
        }

        // If output file already exists return path
        if (file_exists($output_file)) {
            return $output_file;
        }

        $file_type = strtolower(pathinfo($file, PATHINFO_EXTENSION));

        if (function_exists('imagewebp')) {

            switch ($file_type) {
                case 'jpeg':
                case 'jpg':
                    $image = imagecreatefromjpeg($file);
                    break;

                case 'png':
                    $image = imagecreatefrompng($file);
                    imagepalettetotruecolor($image);
                    imagealphablending($image, true);
                    imagesavealpha($image, true);
                    break;

                case 'gif':
                    $image = imagecreatefromgif($file);
                    break;
                default:
                    return false;
            }

            // Save the image
            $result = imagewebp($image, $output_file, $compression_quality);
            if (false === $result) {
                return false;
            }

            // Free up memory
            imagedestroy($image);

            return $output_file;
        } elseif (class_exists('Imagick')) {
            $image = new Imagick();
            $image->readImage($file);

            if ($file_type === 'png') {
                $image->setImageFormat('webp');
                $image->setImageCompressionQuality($compression_quality);
                $image->setOption('webp:lossless', 'true');
            }

            $image->writeImage($output_file);
            return $output_file;
        }

        return false;
    }
}