How does Twitter resolve tweeted images for twitpic, yfrog, instagram

When you select a tweet in twitter the right pane appears. If the tweet has a twitpic, yfrog, or instagram path, it will display the image. Twitte开发者_如何学编程r will do this for video and a few other networks as well. Is there a library available that has this all this functionality or how is this accomplished? I'm mostly interested in resolving images tweeted and am looking for a PHP or JS solution.

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Twitter uses those services' APIs:

http://twitpic.com/api.do

http://code.google.com/p/imageshackapi/

http://instagram.com/developer/

etc.

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use jQuery

$(document).ready(function() {
    $("#contentbox").keyup(function() {
        var content = $(this).val();
        var urlRegex = /(\b(https?|ftp|file):\/\/[-A-Z0-9+&@#\/%?=~_|!:,.;]*[-A-Z0-9+&@#\/%=~_|])/ig;
        // Filtering URL from the content using regular expressions
        var url = content.match(urlRegex);

        if (url.length > 0) {
            $("#linkbox").slideDown('show');
            $("#linkbox").html("<img src='link_loader.gif'>");
            // Getting cross domain data
            $.get("urlget.php?url=" + url, function(response) {
                // Loading <title></title>data
                var title = (/<title>(.*?)<\/title>/m).exec(response)[1];
                // Loading first .png image src='' data
                var logo = (/src='(.*?).png'/m).exec(response)[1];
                $("#linkbox").html("<img src='" + logo + ".png' class='img'/><div><b>" + title + "</b><br/>" + url)
            });

        }
        return false;
    });
});

http://www.9lessons.info/2010/06/facebook-like-extracting-url-data-with.html

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well u can do something like this without using these above libraries. When u get the page with your tweets parse the urls for any images("twitpic" or "yfrog") and then use ajax to silently download the images in the background and then when user selects the tweet u show the image. The hard part is parsing the url to figure out the images. i havent tried this but this should work