1		<?php
			2		/*
			3		*   replacePngTags - Justin Koivisto [W.A. Fisher Interactive] 7/1/2003 10:45AM
			4		*   Modified: 2/11/2004 10:18AM
			5		*
			6		*   Modifies IMG tags for MSIE5+ browsers to ensure that PNG-24 transparencies
			7		*   are displayed correctly.  Replaces original SRC attribute with a transparent
			8		*   GIF file (spacer.gif) that is located in the same directory as the orignal
			9		*   image, and adds the STYLE attribute needed to for the browser. (Matching
			10		*   is case-insensitive. However, the width attribute should come before height.
			11		*
			12		*   Also replaces code for PNG images specified as backgrounds via:
			13		*   background-image: url('image.png'); When using PNG images in the background,
			14		*   there is no need to use a spacer.gif image.
			15		*
			16		*   @param  $x  String containing the content to search and replace in.
			17		*   @result Returns the modified string.
			18		*/
			19		function replacePngTags($x,$spacer="images/spacer.gif")
			20		{
			21		// make sure that we are only replacing for the Windows versions of Internet
			22		// Explorer 5+, and not Opera identified as MSIE
			23		$msie='/msie\s([5-9])\.?[0-9]*.*(win)/i';
			24		$opera='/opera\s+[0-9]+/i';
			25		if(!isset($_SERVER['HTTP_USER_AGENT']) ||
			26		!preg_match($msie,$_SERVER['HTTP_USER_AGENT']) ||
			27		preg_match($opera,$_SERVER['HTTP_USER_AGENT']))
			28		return $x;
			29
			30		// find all the png images in backgrounds
			31		preg_match_all('/background-image:\s*url\(\'(.*\.png)\'\);/Uis',$x,$background);
			32		for($i=0;$i<count($background[0]);$i++){
			33		// simply replace:
			34		//  "background-image: url('image.png');"
			35		// with:
			36		//  "filter:progid:DXImageTransform.Microsoft.AlphaImageLoader(
			37		//      enabled=true, sizingMethod=scale src='image.png');"
			38		// haven't tested to see if background-repeat styles work...
			39		$x=str_replace($background[0][$i],'filter:progid:DXImageTransform.'.
			40		'Microsoft.AlphaImageLoader(enabled=true, sizingMethod=scale'.
			41		' src=\''.$background[1][$i].'\');',$x);
			42		}
			43
			44		// OK, time to find all the IMG tags with ".png" in them
			45		preg_match_all('/(<img.*\.png.*>|<input.*type=([\'"])image\\2.*\.png.*>)/Uis',$x,$images);
			46		while(list($imgnum,$v)=@each($images[0])){
			47		$original=$v;
			48		$atts=''; $width=0; $height=0;
			49		// If the size is defined by styles, find
			50		preg_match_all('/style=".*(width: ([0-9]+))px.*'.
			51		'(height: ([0-9]+))px.*"/Ui',$v,$arr2);
			52		if(is_array($arr2) && count($arr2[0])){
			53		// size was defined by styles, get values
			54		$width=$arr2[2][0];
			55		$height=$arr2[4][0];
			56		}
			57		// size was not defined by styles, get values
			58		preg_match_all('/width=\"?([0-9]+)\"?/i',$v,$arr2);
			59		if(is_array($arr2) && count($arr2[0])){
			60		$width=$arr2[1][0];
			61		}
			62		preg_match_all('/height=\"?([0-9]+)\"?/i',$v,$arr2);
			63		if(is_array($arr2) && count($arr2[0])){
			64		$height=$arr2[1][0];
			65		}
			66		preg_match_all('/src=\"([^\"]+\.png)\"/i',$v,$arr2);
			67		if(isset($arr2[1][0]) && !empty($arr2[1][0]))
			68		$image=$arr2[1][0];
			69		else
			70		$image=NULL;
			71
			72		// We do this so that we can put our spacer.gif image in the same
			73		// directory as the image
			74		$tmp=split('[\\/]',$image);
			75		array_pop($tmp);
			76		$image_path=join('/',$tmp);
			77		if(strlen($image_path)) $image_path.='/';
			78
			79		// end quote is already supplied by originial src attribute
			80		$replace_src_with=$spacer.'" style="width: '.$width.
			81		'px; height: '.$height.'px; filter: progid:DXImageTransform.'.
			82		'Microsoft.AlphaImageLoader(src=\''.$image.'\', sizingMethod='.
			83		'\'scale\')';
			84
			85		// now create the new tag from the old
			86		$new_tag=str_replace($image,$replace_src_with,$original);
			87
			88		// now place the new tag into the content
			89		$x=str_replace($original,$new_tag,$x);
			90		}
			91		return $x;
			92		}
			93		?>