[QnA] Convert MOD to AVI using transcode -- without audio ouput

Sometimes we might take videos with some environmental noise or conversations which are not suitable to be heard by others. Also, we don't need or want to add other audio into the original video, so just export the video without audio is fine enough.

I had some MOD files to be converted by using transcode before, and this time I want to export my MOD files into avi files with no sound. It's can be done by apply the ``null'' option as the following

transcode -i input.MOD -y xvid,null -o output.avi

That's all.