YouTube To Go

Let me start with a disclaimer that I’m not endorsing the distribution of YouTube videos in other video formats or even saving them to your computer. This was simply a proof of concept of taking a video from YouTube and having the ability to watch it offline. Also, with my never-ending quest to master FFmpeg and it’s encoding capabilities I wanted to see if I could encode Flash video files to QuickTime. I’ve spent a lot of time learning how to encode different video formats to FLV and thought it would be interesting to go in the other direction.

This howto was accomplished using the following tools: Live HTTP headers for Firefox and FFmpeg on Linux. I can’t see this being any different for Windows, but would like to hear if the process varies. I decided to start with the crazy video of this guy flying a tiny twin engine airplane:

When the video starts playing a request is made YouTube’s servers asking for the appropriate FLV file. This can be viewed through Live HTTP headers as seen below:

If you copy this URL and paste it in your browser you’ll be prompted to save this file to your computer. The original file size for this file was about 8MB. After saving it all you need to do is fire up FFmpeg and run the following command:

ffmpeg -i PlV8WJ6N3nU.flv -ab 32 -ar 22050 -b 256 -s 320×240 youtube.mpg

Let the encoding begin:

You can feel free to tweak the values I’ve specified for each of the parameters depending on your desired audio/video quality. The values listed above are ones that I’ve found to deliver a QuickTime video near the same quality as the original. Let me briefly describe the params:

-i input file name
-ab set audio bitrate (in kbit/s)
-ar set audio sampling rate (in Hz)
-b set video bitrate (in kbit/s)
-s set frame size (WxH or abbreviation)
and the last, of course, is the output file name. After encoding the resulting QuickTime file as about 7MB. Now all you need to do is fire up your QuickTime player and watch the vid:

It shouldn’t take much effort to encode your video to other formats as well.  Since I wanted to watch videos on my Mac I decided to go with QuickTime.  This process is fairly straight forward and feel free to drop me a comment if you have any problems.

One again: I’m not suggesting this is something you should do.  This was a proof of concept to demonstrate the power of FFmpeg and what better place to grab an FLV file then from YouTube.  Enjoy.