First we should know Youtube download URL summary:
Youtube videos can be downloaded from the URL http://youtube.com/get_video.php?
The summary of the script:
Download the source of the page of the URL http://in.youtube.com/watch?v=VDAGIFjt6m4
(
More detailed algorithm.
1) Get the page source from Youtube using the public URL - http://in.youtube.com/watch?v=VDAGIFjt6m4
In the example VDAGIFjt6m4 is the ID. The ID can change depending upon your video.
2) The source will be entire page which has the Youtube video embedded we are only interested in the following HTML -
var swfArgs = {"BASE_YT_URL": "http://in.youtube.com/", "vq": null, "sourceid": "y", "video_id": "VDAGIFjt6m4", "l": 65, "sk": "mkKFIRWXheJgUGsaU6Bx2LsnWvZldVraC", "fmt_map": "6/720000/7/0/0", "t": "OEgsToPDskK0DEe01pPPKzJJ700ykmac", "hl": "en", "plid": "AARWNMbnD8zgFCZ0AAAAoAAYAAA", "sdetail": "p%3A/"};
3) Extract the interested line using the following Regular Expression "swfArgs(\\s*)=(\\s*)\\{(.*)\\}"
var ytPattern = "swfArgs(\\s*)=(\\s*)\\{(.*)\\}";
var re = new RegExp(ytPattern);
var matchVar = eval('({' + re.exec(strDoc) + '})');
Now from matchVar get the values like matchVar['video_id'] or matchVar['sk']
Once you the values substitute in
http://youtube.com/get_video.php?video_id=
Disclaimer: If Youtube changes its page this script will not work. This is working as of Sept 6 2008.
