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9 years ago I've been experiencing the same behavior and did some investigation. I found
that for my subscriptions youtube has added more formats recently than I've had
in the past. There is a format map variable in the javascript code that breaks
out to something like this:
37/1920x1080/9/0/115,
22/1280x720/9/0/115,
35/854x480/9/0/115,
34/640x360/9/0/115,
18/640x360/9/0/115,
5/320x240/7/0/0
The first value is the id (some of these are used by rsshandler currently).
Now the rub comes in videoservlet.java. It runs a regex across the entire page
for the video to try to find the binary you desire. This is a group match and
it grabs the first result it finds on the page. I'm not sure how this worked
with youtube previously, but whatever they changed now makes it select a much
higher resolution (depending on what is available).
I pulled down the code and made a small POC hack videoservlet.java to see if I
could get a lower resolution (and thus file size). I found that the ids in the
format map appear to map to a url parameter named itag that getVideoLink2
returns. I changed getVideoLink2 to the following:
private String getVideoLink2(String content, int fmt) throws
UnsupportedEncodingException {
Pattern pattern = Pattern.compile("%7C(http.+?videoplayback.+?)%2C");
Matcher matcher = pattern.matcher(content);
String format = "%26itag%3D" + fmt + "%26";
String url = null;
while (matcher.find()) {
String u = matcher.group(1);
if (u.indexOf(format) > -1) {
logger.info("getVideoLink2: match (" + u + ") for format " + fmt);
url = u;
break;
}
}
if (url != null) {
return URLDecoder.decode(url, "UTF-8");
}
throw new IllegalStateException("Cann't find video file address: "+ content);
}
The call in doGet needs a slight modification as well:
String redirect = getVideoLink2(str,format);
This by no means complete, but thought I would share my analysis so far.Original comment by jeromeku...@gmail.com on 13 Dec 2010 at 6:33
Original issue reported on code.google.com by
Jorge.Me...@gmail.comon 8 Dec 2010 at 3:14