If you don't wish to use regex (or any non-standard PHP components), a reasonable solution using the built-in DOMDocument class would be as follows:

<?php
    $doc = new DOMDocument();
    $doc->loadHTML('<img src="http://example.com/img/image.jpg" ... />');
    $imageTags = $doc->getElementsByTagName('img');

    foreach($imageTags as $tag) {
        echo $tag->getAttribute('src');
    }
?>

Code

<?php
    $foo = '<img class="foo bar test" title="test image" src="http://example.com/img/image.jpg" alt="test image" width="100" height="100" />';
    $array = array();
    preg_match( '/src="([^"]*)"/i', $foo, $array ) ;
    print_r( $array[1] ) ;

Output

http://example.com/img/image.jpg

I got this code:

$dom = new DOMDocument();
$dom->loadHTML($img);
echo $dom->getElementsByTagName('img')->item(0)->getAttribute('src');

Assuming there is only one img :P

// Create DOM from string
$html = str_get_html('<img class="foo bar test" title="test image" src="http://example.com/img/image.jpg" alt="test image" width="100" height="100" />');

// echo the src attribute
echo $html->find('img', 0)->src;

http://simplehtmldom.sourceforge.net/

Here's what I ended up doing, although I'm not sure about how efficient this is:

$imgsplit = explode('"',$data);
foreach ($imgsplit as $item) {
    if (strpos($item, 'http') !== FALSE) {
        $image = $item;
        break;
    }
}

try this pattern:

'/< \s* img [^\>]* src \s* = \s* [\""\']? ( [^\""\'\s>]* )/'

You can go around this problem using this function:

function getTextBetween($start, $end, $text)
{
 $start_from = strpos($text, $start);
 $start_pos = $start_from + strlen($start);
 $end_pos = strpos($text, $end, $start_pos + 1);
 $subtext = substr($text, $start_pos, $end_pos);
 return $subtext;
}

$foo = '<img class="foo bar test" title="test image" 
src="http://example.com/img/image.jpg" alt="test image"
width="100" height="100" />';

$img_src = getTextBetween('src="', '"', $foo);

<?php
    $html = '
        <img border="0" src="/images/image1.jpg" alt="Image" width="100" height="100" />
        <img border="0" src="/images/image2.jpg" alt="Image" width="100" height="100" />
        <img border="0" src="/images/image3.jpg" alt="Image" width="100" height="100" />
        ';
    
    $get_Img_Src = '/<img[^>]*src=([\'"])(?<src>.+?)\1[^>]*>/i'; //for get img src path only...
    
    preg_match_all($get_Img_Src, $html, $result); 
    if (!empty($result)) {
        echo $result['src'][0];
        echo $result['src'][1];
    }

for get img src path & alt text also then use below regex instead of above...

<img[^>]*src=(['"])(?.+?)\1[^>]alt=(['"])(?.+?)\2>

    $get_Img_Src = '/<img[^>]*src=([\'"])(?<src>.+?)\1[^>]*alt=([\'"])(?<alt>.+?)\2*>/i'; //for get img src path & alt text also
    
    preg_match_all($get_Img_Src, $html, $result); 
    if (!empty($result)) {
        echo $result['src'][0];
        echo $result['src'][1];
        echo $result['alt'][0];
        echo $result['alt'][1];
    }

I got idea of that great solution from here, PHP extract link from a href tag

I use preg_match_all to capture all images in HTML document:

preg_match_all("~<img.*src\s*=\s*[\"']([^\"']+)[\"'][^>]*>~i", $body, $matches);

This one allows more relaxed syntax of declaration, with spaces and different quote types.

Regex reads like <img (any attributes like style or border) src (possible space) = (possible space) (' or ") (any non-quote symbol) (' or ") (anything until >) (>)