Rodion Adamkiewicz
Rodion Adamkiewicz voted up Amy Wong's answer

I recommend you Kigo Video Converter.

Actually, it is easy for developers to design a program to convert video file formats.

However, some paid programs have extra functions like clip segment, crop, add watermark and more.

Kigo Video Converter is an all-in-one video converter. View more info at 

Wonderful software,  star programers!