Youtube – What happened to YouTube download URLs

youtube

Note: This question is about download URLs, not software. The question "How do I download a YouTube video?" deals with software.

What exactly changed for YouTube download URLs a few days ago? How should YouTube download URLs be formed now?

The following URL used to work (downloading this Flash video to disk) but no longer works since the change:

http://www.youtube.com/get_video.php?video_id=DYW50F42ss8&t=vjVQa1PpcFPDxa83Hr1_9pftRUWdsMyJ10a2o8QZvIs=

Note: the following information is only to illustrate the problem. I am only interested in the information about how to form download URLs.

This change affected quite a few tools. Here are leads from some Firefox plug-in homepages:

From Video DownloadHelper 4.7.4, 2010-07-22:

"As many of the users noticed,
Video DownloadHelper does not work well on YouTube since
today. This is due to a very recent change at YouTube.
We made a fix that seems to work ok. "

From Easy YouTube Video Downloader 3.4, 2010-07-24:

"Please update to latest version 3.5
in sandbox to get it working again with latest Youtube
changes"

From YouTube Downloader, 2010-07-24:

"YouTube has updated their website in a way that breaks YouTube Downloader 2.5.6 and older. We are working on version 2.6 which fixes this problem."


Related: "How do I download a YouTube video?". Some of those tools may be broken now!

Best Answer

I am unsure what changed, but I suspect YouTube changed their URLs so you can not get a video without matching cookies. This prevents 3rd party sites from showing you ads and giving you download links.

I can tell you this link (pasted at the very bottom), which I got from your video, WORKS for me. However if I paste it in my other instance of Firefox (which has different cookies for the site) this link does NOT work.

I suggest using a userscript. I like YouTube Enhancer.

If you need to do this in code I do see the link(s?) in var swfConfig =

http://v12.lscache4.c.youtube.com/videoplayback?ip=0.0.0.0&sparams=id%2Cexpire%2Cip%2Cipbits%2Citag%2Calgorithm%2Cburst%2Cfactor%2Coc%3AU0dXRVFRTl9FSkNNN19JS1JB&fexp=903205%2C906501&algorithm=throttle-factor&itag=34&ipbits=0&burst=40&sver=3&expire=1280160000&key=yt1&signature=2F2BB59B9BA3E6AB62CEE47F597D7A4D96002893.03196019F468211FAA4E492F7F5B1951951AEAF9&factor=1.25&id=0d85b9d05e36b2cf&title=Tom%20Lehrer%20CHEMISTRY%20element%20song

to make it easy for me to read I did a full escape using this handy script.

http://v12.lscache4.c.youtube.com/videoplayback?ip=0.0.0.0&sparams=id,expire,ip,ipbits,itag,algorithm,burst,factor,oc:U0dXRVFRTl9FSkNNN19JS1JB&fexp=903205,906501&algorithm=throttle-factor&itag=34&ipbits=0&burst=40&sver=3&expire=1280160000&key=yt1&signature=2F2BB59B9BA3E6AB62CEE47F597D7A4D96002893.03196019F468211FAA4E492F7F5B1951951AEAF9&factor=1.25&id=0d85b9d05e36b2cf&title=Tom Lehrer CHEMISTRY element song