Oh! its sad to see what I saw. I am downloading a file from youtube (the video is of 1 hr) using command line from Ubuntu13.04 as below:
ravbholua@ravbholua-Aspire-5315:~$ youtube-dl "http://www.youtube.com/watch?v=d4Z8VI3myBw" [youtube] Setting language [youtube] d4Z8VI3myBw: Downloading video webpage [youtube] d4Z8VI3myBw: Downloading video info webpage [youtube] d4Z8VI3myBw: Extracting video information [download] Destination: d4Z8VI3myBw.mp4 [download] 0.1% of 718.62M at 13.70k/s ETA --:--
See the size is 718 MB and type is mp4.
The same file I downloaded earlier from Windows 7 OS using youtube downloader. Then the type and size of the file was flv and 130 MB only.
Similarly, yesterday and today I downloaded files from youtube via my Ubuntu13.04 and all were downloaded as mp4 and very very big size. But when I downloaded many videos via Windows earlier all the files had flv type and very less size as compared to mp4.
I can't download youtube videos if they are downloaded like this (mp4 with big sizes).
One thing is clear: the difference lies with the OS and/or the youtube downloader for Windows7. What setting needs to be changed please here in Ubuntu13.04?