Php str_replace with &quote not working - php

Question

my code is:
$retval = preg_match('/<img.+src=[\'"](?P<src>.+)[\'"].*>/i', $content, $image);
$imgreal = str_replace(""", "\"", $image['src']);
if ($retval=="0") $imgthumb = ""; else $imgthumb = "<img align='left' src='".$imgreal."' width=100 />";
I need to extract an img from a string, but this gave me all time:
"http://www.racingzone.hu/pictures/news/mid/simroc-3---nyolc-uj-auto_2012-09-21-1348222495.jpg" alt="" width="490" height="214
How can I change those &quotes to normal chars "?
I tried htmlspecialchars_decode but that not worked to.
edit: the string coming from az sql table.
original string from mysql:
<p><img style="float: left; margin: 3px;" src="http://www.racingzone.hu/pictures/news/mid/simroc-3---nyolc-uj-auto_2012-09-21-1348222495.jpg" alt="" width="490" height="214" /></p>
<p>todik púőúőóüsztotodik púőúőóüsztotodik
string created by TinyMCE
coding in the table: latin2_hungarian_ci

Answer 1

Why does everybody always want to do these kind of things with a regex?
Simply:
$data='<p><img style="float: left; margin: 3px;" src="http://www.racingzone.hu/pictures/news/mid/simroc-3---nyolc-uj-auto_2012-09-21-1348222495.jpg" alt="" width="490" height="214" /></p>
<p>todik púőúőóüsztotodik púőúőóüsztotodik';
$a=explode('src="',$data);
if(count($a)<2)
{
echo 'no image';
die;
}
$p=strpos($a[1],'"',0);
if($p===false){
echo 'no quote found';
die;
}
$url=substr($a[1],0,$p);
echo $url;
Output:
http://www.racingzone.hu/pictures/news/mid/simroc-3---nyolc-uj-auto_2012-09-21-1348222495.jpg