I have just released my first Google Chrome extension which lets you download YouTube videos in .flv format to your computer directly from your browser. It’s called YouVid.
Several extensions like this exist: many do not work anymore, others let you only download the videos through a 3rd-party encoding provider.

I wanted an extension that would let me download videos in plain .flv/.mp4 format for further work. And here it is.

NOTE: does not work in incognito mode, due to restrictions set by YouTube that do not allow access to the stream without some cookies set.

Download and instructions

You can download the YouVid extension here. Obviously, you will need Google Chrome.

Please note that using this extension might represent a breach of the YouTube acceptable user policy (AUP): this extension is for demonstration purpouses only, and I assume no responsibility for any action regarding the usage of this software. By using this extension, you accept these terms.

Conversion of FLV/MP4 and playing FLV videos tips

The extension downloads either a .flv or an .mp4 file: this depends on whether YouTube has the .mp4 format or not for that specific video.
More specifically, if you find a .flv video Google Chrome should download it automatically. Otherwise, you will end you playing it in your browser, and you can save the .mp4 by right clicking on it->save.

You might want to play the resulting FLV/MP4 file, or you might want it to convert to, say, .avi or .mpg.
That is reasonable. How could you do that?

• In order to play FLV videos, you could use lots of programs you can find with this Google search
• In order to convert files (both FLV and MP4), the best opensource tool out there is ffmpeg: a simple command such as
  
ffmpeg -i filename.flv filename.mpg

  or
  
ffmpeg -i filename.mp4 filename.avi

  will convert the file you downloaded with the extension. However, if you want to use some program with a GUI, you could use lots of programs you can find with this Google search.

If you want further information about my projects, please visit my software section.