STREAM::expression regex

I don't think you need to rewrite this:

img src="~/0.jpg"

to the fully qualified URL of this:

img src="http://devcentral.f5.com/0.jpg"

as a local URI of /0.jpg should be rendered using the same hostname the client made the request to.

You might be able to get away with just replacing any instance of ~/ with /. Or maybe /~/ with / and ~/ with / STREAM::expression {@/~/@/@ @~/@@}

when HTTP_REQUEST {
    Disable the stream filter by default
   STREAM::disable
}
when HTTP_RESPONSE {
     Disable the stream filter by default
    STREAM::disable
     Enable the stream filter for text responses only
    if {[HTTP::header value Content-Type] contains "text"}{
         Replace '~/' with '/'
        STREAM::expression {@~/@/@}
         Enable the stream filter for this response only
        STREAM::enable
    }
}

Or if you want to make the matching more specific and only look within img src tags, you could use something like this:

when HTTP_REQUEST {
    Disable the stream filter by default
   STREAM::disable
}
when HTTP_RESPONSE {
     Disable the stream filter by default
    STREAM::disable
     Enable the stream filter for text responses only
    if {[HTTP::header value Content-Type] contains "text"}{
         Match on img src tags with a ~/ in them
        STREAM::expression {@]*?~/@@}
         Enable the stream filter for this response only
        STREAM::enable
    }
}
when STREAM_MATCHED {
    log local0. "Matched: [STREAM::match], replacing with [string map {~/ /} [STREAM::match]]"
    switch -glob [STREAM::match] {
        "*~/*" {
             Replace ~/ with /
            STREAM::replace [string map {~/ /} [STREAM::match]]
        }
    }
}

If neither of these approaches work, can you reply with the debug logging from /var/log/ltm and give more detail on what hostname the client is requesting and how you want to rewrite the response content?

Aaron