<?php
class images{
	function imageWrite($src,$watermark){
		header('content-type: image/jpeg');
		$extention=array("jpg","jpeg","gif","png","JPG","JPEG","GIF","PNG");
		$get_wtr_ext=substr($watermark,strripos($watermark,".")+1,strlen($watermark));
		if (!in_array($get_wtr_ext,$extention)){
			echo "bad_extension";
		}
		if ($get_wtr_ext == "jpg" || $get_wtr_ext == "jpeg" || $get_wtr_ext == "JPG" || $get_wtr_ext == "JPEG"){
			$watermark_create=imagecreatefromjpeg($watermark);
		}elseif ($get_wtr_ext == "png" || $get_wtr_ext == "PNG"){
			$watermark_create=imagecreatefrompng($watermark);
		}elseif ($get_wtr_ext == "gif" || $get_wtr_ext == "GIF"){
			$watermark_create=imagecreatefromgif($watermark);
		}
		$watermark_width=imagesx($watermark_create);
		$watermark_height=imagesy($watermark_create);
		$image=imagecreatetruecolor($watermark_width,$watermark_height);
		$get_src_ext=substr($src,strripos($src,".")+1,strlen($src));
		if ($get_src_ext == "jpg" || $get_src_ext == "jpeg" || $get_src_ext == "JPG" || $get_src_ext == "JPEG"){
			$image=imagecreatefromjpeg($src);
		}elseif ($get_src_ext == "png" || $get_src_ext == "PNG"){
			$image=imagecreatefrompng($src);
		}elseif ($get_src_ext == "gif" || $get_src_ext == "GIF"){
			$image=imagecreatefromgif($src);
		}
		$size=getimagesize($src);
		$dest_x = $size[0] - $watermark_width - 5;
		$dest_y = $size[1] - $watermark_height - 5;
		imagecopymerge($image,$watermark,$dest_x,$dest_y,0,0,$watermark_width,$watermark_height,100);
		imagejpeg($image);
	}
}
$obj=new images();
$obj->imageWrite("ds.jpg","test.gif");
?>

function imageWrite($src,$watermark){
		preg_match("'^(.*)\.(gif|jpe?g|png)$'i", $watermark, $ext);
		switch (strtolower($ext)) {
			case 'jpg' :
			case 'jpeg': $watermark   = imagecreatefromjpeg ($watermark);
			break;
			case 'gif' : $watermark   = imagecreatefromgif  ($watermark);
			break;
			case 'png' : $watermark   = imagecreatefrompng  ($watermark);
			break;
		}
		$watermark_width = imagesx($watermark);
		$watermark_height = imagesy($watermark);
		$image = imagecreatetruecolor($watermark_width, $watermark_height);
		$image = imagecreatefromjpeg($src);
		$size = getimagesize($src);
		$dest_x = $size - $watermark_width - 5;
		$dest_y = $size - $watermark_height - 5;
		imagecopymerge($image, $watermark, $dest_x, $dest_y, 0, 0, $watermark_width, $watermark_height, 100);
		imagejpeg($image);
		imagedestroy($image);
		imagedestroy($watermark);
	}
}