get png by path, convert to jpg, compress 100 and replace file with jpg extension

<?php
$path = "";

$img = new Imagick($path);
$img->setImageFormat("jpg");
$img->setImageCompression(Imagick::COMPRESSION_JPEG);
$img->setImageCompressionQuality(100);
$img->stripImage();
$img->writeImage("");
$img->clear();
$img->destroy();
?>