public function tifToJpg($filename){

$filepath = 'D:/xampp/htdocs//';

$jpgfilename = substr($filename,0,strrpos($filename,'.')).'.jpg';

$im = new Imagick($filepath.$filename);

$im->thumbnailImage(750, 0);

$width = $im->getImageWidth() ;

$height = $im->getImageHeight();

$width800 = 800;

$height800 = 800*$height/$width;

$canvas = new Imagick();

$canvas->newImage($width, $height, '');

$canvas->setImageFormat("jpeg");

$canvas->compositeImage($im, imagick::COMPOSITE_OVER, 20, 10);

$canvas->writeImage($filepath.$jpgfilename);

return $jpgfilename;

}