In this tutorial we will use VirtualDub which is an extremely efficient video capture and processing program. It can be used to compress an MJPEG AVI file (digital camera’s usually save in this format) to Divx/Xvid AVI video with MP3 audio.
How to compress AVI Video using VirtualDub – Guide
First we need to download VirtualDub. Extract the zip file and open the VirtualDub application.
Choose File > Open Video File (Ctrl+O)
Select the file you wish to open. You should see a screen similar to the one below.
Now from the Video menu choose Compression (Ctrl+P). We will be using the Xvid MPEG-4 codec for compressing this file (Divx is also a good choice but Xvid is opensource). Incase you do not see it, download Xvid.
Choose Xvid MPEG-4 Codec and click Configure. Now click on target quatizer, the button will change to Target bitrate. Enter 300-350, which is a good rate for videos to be shared on the web. You can enter a higher rate if you like. Click Ok on both the boxes to get back to the main screen.
Now go to the Audio menu and choose Full Processing Mode.
Again go to the Audio menu and choose Compression. Choose MPEG Layer-3, check Show all Formats. Choose a bitrate for the audio, 128kBit/s should be enough.
Last but not least go to File > Save as AVI (F7). Choose a location and name to save the file.
VirtualDub will now compress the file. In my case, the 800MB file was compressed to 80MB while loosing a little quality. A small price to pay for a huge reduction in file size. Play with the bitrate setting to your liking.