How to compress video file size without losing quality

If You're uploading large videos to YouTube or You just want to save some space on Your computer, this is great tutorial for You!


 First You will need to download VirtualDub and XVID MPEG4 Codec for compression (Links are below)
DOWNLOAD VIRTUAL DUB
DOWNLOAD XVID MPEG4 

After You have downloaded VirtualDub and Xvid, You have to install Xvid codec, but not VirtualDub because it's portable and doesn't require installation to run.

Now we can move to video compression.
1.) Open VirtualDub
2.) Click "File" - "Open video file ...", locate Your video and click "Open"
3.) Go back to VirtualDub, click "Video" and check/tick "Full processing mode
4.) Now click "Video" again and click "Compression" from drop-down menu
5.) Select XVID MPEG4 codec (by left clicking on it) and click "Configure" 
6.) THIS STEP IS UP TO YOU! Now You have to set slider bewtween 1 and 31 (1 - higher quality and bigger files, 31 - worse quality and small files) and click OK
7.) Go back to VirtualDub and click "Audio" 
8.) Tick "Full processing mode"
9.) Click "Audio" and then "Compression" from drop-down menu
10.) Select MPEG3 -Layer, click OK
11.) Go back to VirtualDub: "File" -> "Save as AVI..."

Now You have to wait untill compression is done. If You're not satisfied with results, do the same steps, but move slider little bit more to left for better quality.