If you're willing to invest a few minutes in learning about modules (HTML::Parser and HTML::TokeParser come to mind -- follow the link to CPAN) rather than a few minutes banging your head against the wall figuring out how to catch corner cases with regular expressions, it will pay off greatly.

If all of the HTML is very similar and not too tricky, you can use a regexp like: $line = s!(<img src=")[^"]+([^>]*">)!$1$newimage$2!gi; to do your substitution. Be warned, using regular expressions on HTML is very tricky, unless you're dealing with extremely consistent HTML.

In reply to Re: Extract and modify IMG SRC tags in an HTML document. by chromatic
in thread Extract and modify IMG SRC tags in an HTML document. by jmpvm

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.