youtube-downloader

run with PHP

copy code to your directory

open url http://YOUR_URL/PATH/TO/FILE/index.php?v=YOUTUBE_ID

How to merge Video and Audio with VLC

1. file > advanced open file
2. select tab file
3. browse video file
4. checked Play another media synchronously and browse audio file
5. checked Streamimg/Saving and click setting...
6. browse file for save output
7. select mpeg 4
8. click OK
9. click open and wait